12
CLIMATE
CHANGE
RESEARCH
REPORT
CCRR-12
Responding to
Climate Change
Through Partnership
Ontario’s Forests and
Forestry in a Changing
Climate
Climate Change and MNR: A Program-Level Strategy and Action Plan
The following describes how the Ministry of Natural Resources
works to contribute to the Ontario Government’s commitment to
reduce the rate of global warming and the impacts associated
with climate change. The framework contains strategies and substrategies organized according to the need to understand climate
change, mitigate the impacts of rapid climate change, and help
Ontarians adapt to climate change:
Strategy #6: Establish on-site management programs
designed to plan ecologically, manage carbon sinks, reduce
greenhouse gas emissions, and develop tools and techniques
that help mitigate the impacts of rapid climate change. Onsite land use planning and management techniques must be
designed to protect the ecological and social pieces, patterns,
and processes. Accordingly, MNR will work to:
Theme 1: Understand Climate Change
•
•
•
•
Strategy #1: Gather and use knowledge in support of informed
decision-making about climate change. Data and information
gathering and management programs (e.g., research, inventory, monitoring, and assessment) that advances our knowledge
of ecospheric function and related factors and forces such as
climate change are critical to informed decision-making. Accordingly, MNR will work to:
• Strategy 1.A: Develop a provincial capability to describe,
predict, and assess the important short- (0-5 years), medium(5-20 years), and long-term (20+ years) impacts of climate
change on the province’s ecosystems and natural resources.
• Strategy 1.B: Model the carbon cycle.
Strategy #2: Use meaningful spatial and temporal frameworks
to manage for climate change. A meaningful spatial and temporal
context in which to manage human activity in the ecosphere and
address climate change issues requires that MNR continue to
define and describe Ontario’s ecosystems in-space and time. In
addition, MNR will use the administrative and thematic spatial
units required to manage climate change issues.
Theme 2: Mitigate the Impacts of Climate Change
Strategy #3: Gather information about natural and cultural
heritage values and ensure that this knowledge is used as part of
the decision-making process established to manage for climate
change impacts. MNR will continue to subscribe to a rational
philosophy and corresponding suite of societal values that equip
natural resource managers to take effective action in combating
global warming and to help Ontarians adapt to the impacts of
climate change.
Strategy #4: Use partnership to marshal a coordinated response
to climate change. A comprehensive climate change program
involves all sectors of society as partners and participants in
decision-making processes. The Ministry of Natural Resources
will work to ensure that its clients and partners are engaged.
Strategy #5: Ensure corporate culture and function work in
support of efforts to combat rapid climate change. Institutional
culture and function provide a “place” for natural resource
managers to develop and/or sponsor proactive and integrated
programs. The Ministry of Natural Resources will continue to provide a “home place” for the people engaged in the management
of climate change issues.
Strategy 6.A: Plan ecologically.
Strategy 6.B: Manage carbon sinks.
Strategy 6.C: Reduce emissions.
Strategy 6.D: Develop tools and techniques to mitigate the
impacts of rapid climate change.
Theme 3: Help Ontarians Adapt
Strategy #7: Think and plan strategically to prepare for natural
disasters and develop and implement adaptation strategies.
MNR will sponsor strategic thinking and planning to identify, establish, and modify short- and long-term direction on a regular
basis. Accordingly, MNR will work to:
• Strategy 7.A: Sponsor strategic management of climate
change issues.
• Strategy 7.B: Maintain and enhance an emergency response
capability.
• Strategy 7.C: Develop and implement adaptation strategies
for water management and wetlands.
• Strategy 7.D: Develop and implement adaptation strategies
for human health.
• Strategy 7.E: Develop and implement adaptation strategies
for ecosystem health, including biodiversity.
• Strategy 7.F: Develop and implement adaptation strategies
for parks and protected areas for natural resource-related
recreational opportunities and activities that are pursued
outside of parks and protected areas.
• Strategy 7.G: Develop and implement adaptation strategies
for forested ecosystems.
Strategy #8: Ensure policy and legislation respond to climate
change challenges. Policy, legislation, and regulation guide development and use of the programs needed to combat climate
change. MNR will work to ensure that its policies are proactive,
balanced and realistic, and responsive to changing societal
values and environmental conditions.
Strategy #9: Communicate. Ontarians must understand global
warming, climate change, and the known and potential impacts
in order to effectively and consistently participate in management programs and decision-making processes. Knowledge
dissemination through life-long learning opportunities that are
accessible and current is critical to this requirement. MNR will
raise public understanding and awareness of climate change
through education, extension, and training programs.
Ontario’s Forests and Forestry in a
Changing Climate
S. J. Colombo
Ontario Forest Research Institute
Ontario Ministry of Natural Resources
1235 Queen Street East
Sault Ste. Marie, Ontario, Canada
2008
Applied Research and Development Branch
Ontario Ministry of Natural Resources
300 Water Street,
Peterborough, ON, K9J 8M5
Applied Research and Development Branch • Ontario Ministry of Natural Resources
Library and Archives Canada Cataloguing in Publication Data
Colombo, S. J. (Stephen John)
Forests and forestry in a changing climate [electronic resource] / S.J. Colombo
(Climate change research report ; CCRR-12)
Electronic monograph in PDF format.
Includes bibliographical references.
Issued also in printed form.
ISBN 978-1-4249-7495-5
1. Forest microclimatology—Ontario. 2. Climatic changes—Environmental aspects
—Ontario. 3. Forests and forestry—Ontario—Forecasting. 4. Forest management—Environmental aspects—
Ontario. I. Ontario. Ministry of Natural Resources. Applied Research and Development Branch. II Title. III.
Series: Climate change research report (Online) ; CCRR-12.
SD390.7.C55 C64 2008
577. 3’72209713
2008-964024-1
© 2008, Queen’s Printer for Ontario
Printed in Ontario, Canada
Single copies of this publication
are available from:
Applied Research and Development
Ontario Forest Research Institute
Ministry of Natural Resources
1235 Queen Street East
Sault Ste. Marie, ON
Canada P6A 2E5
Telephone: (705) 946-2981
Fax: (705) 946-2030
E-mail: information.ofri@ontario.ca
Cette publication hautement spécialisée Ontario’s Forests and Forestry in a Changing Climate n’est
disponible qu’en anglais en vertu du Règlement 411/97, qui en exempte l’application de la Loi sur les
services en français. Pour obtenir de l’aide en français, veuillez communiquer avec le ministère de
Richesses naturelles au information.ofri@ontario.ca.
This paper contains recycled materials.
I
Summary
This report updates a review of literature about the effects of global climate change on forest plants and communities published ten years ago
(Forest Research Information Paper No. 143). Since the previous review, evidence of environmental changes caused by elevated atmospheric
carbon dioxide (CO2) and its potential effects on global climate has strengthened considerably, to the point that there are reports that the effects of
climate change are already being observed. The International Panel on Climate Change (IPCC) indicates that rates of greenhouse gas emissions
continue to increase due to fossil fuel burning and deforestation. Based on a less-than-worst-case scenario, the IPCC “A2” scenario, and modelled
using the Canadian Global Climate Model (CGCM2), increased atmospheric CO2 is projected to increase average summer temperatures in Ontario
between 3°C and 6°C by 2070, with the largest increases in the far north but with heavily populated parts of the province warming by 4°C to
5°C. Growing season precipitation is predicted to increase only slightly (<10%) in much of Ontario, and to decrease in southern and northwestern
Ontario. Projected increases in summer temperatures with no or little increase in precipitation would increase the frequency and severity of
drought by elevating evapotranspiration.
One predictable response to drier forests is increased forest area burned. The projected increase is for a doubling of area burned in parts of
the province where ire suppression is not practiced. In the managed forest, however, where more people live and where forests are more heavily
used for timber production and recreation, most ires are currently able to be suppressed through early action. However, under severe ire weather
conditions, initial attack at present can be unsuccessful, and climate change is expected to increase severe ire weather. As a result, an anticipated
effect of climate change is increased frequency of uncontainable forest ire spread, resulting in more large burns in areas of managed forest.
The complex interactions of trees with insects and disease makes it dificult to project the timing and extent of effects of climate change on
these disturbances. However, if drought increases tree stress, the occurrence and severity of insect and disease outbreaks are likely to increase.
In addition to drought, extreme weather events, such as wind storms, looding, and very high temperatures could stress plants and increase
insect and disease outbreaks. As a result, most important diseases of Ontario trees are expected to increase, and none are anticipated to decline.
Cold winters that have historically kept some insects out of Ontario will occur less frequently, resulting in possible expansions of their ranges. For
example, mountain pine beetle, which in recent years expanded its range into boreal forests in northern Alberta, may reach Ontario’s pine forests
before 2050.
Climate change will increasingly make species and local populations of tree species less well adapted to the climate where they occur. For
some species, this will reduce growth at the centre of their range and increase growth closer to the northern end of their distribution. The long
lives of trees and their slow natural migration means that natural processes will be unable to move seed fast enough to match changing climate.
Increasingly, forest managers will consider planting non-local species and populations. Such potential adaptations, however, need to be carried out
with consideration of potential negative consequences and if implemented should be well documented and monitored.
Risks to forests from implementing adaptation strategies need to be weighed against the risks to forests if chosen actions affect current
species biodiversity. For this reason, a coordinated, science-based approach to forest adaptation can help forest managers determine possible
strategies for reducing the negative effects of climate change. This report describes an approach termed “judicious adaptation”, in which risk of
damage from implementing an adaptation is weighed against the risk of not acting. Adaptations carrying high risk would require strong evidence
that failing to act creates an imminent threat. Low risk strategies would have a requirement for documentation of results to allow improved
understanding of the risks and beneits of undertaking the adaptation. Judicious adaptation has similarities to the adaptive management approach,
because of the requirements for planning and monitoring in both.
According to the IPCC, sustainable forest management that maintains forest carbon stocks and provides a sustained yield of wood products
provides the best long-term climate change mitigation strategy for forests. Wood products from forests store carbon, but also can reduce
greenhouse gas emissions from fossil fuels by using wood as an alternative energy source (either burned directly or burning methane generated
by wood products in landills). Solid wood products have considerably lower energy intensity than building materials such as steel, aluminum,
brick, and concrete. Therefore, using wood in place of such other materials reduces emissions of greenhouse gases and is an indirect way that
forests can contribute to mitigating climate change.
Résumé
Les auteurs du présent rapport actualisent une étude documentaire publiée il y a dix ans (Forest Research Information Paper No. 143)
au sujet des effets du changement climatique sur les plantes et les communautés forestières. Depuis la rédaction du rapport précédent,
les preuves de changements environnementaux causés par la forte concentration de gaz carbonique (CO2) dans l’atmosphère et ses
répercussions potentielles sur le climat de la Terre sont beaucoup plus évidentes, certains rapports indiquant que les effets du changement
climatique sont déjà observables. Le Groupe d’experts intergouvernemental sur l’évolution du climat (GIEC) fait valoir que les taux d’émission
de gaz à effet de serre continuent d’augmenter en raison de l’emploi de combustibles fossiles et de la déforestation. Selon le scénario « A2 »
du GIEC, négatif sans toutefois être le plus pessimiste, et le modèle canadien de circulation générale (MCCG2), la concentration accrue
de CO2 dans l’atmosphère pourrait faire monter les températures estivales moyennes en Ontario de 3 à 6 °C d’ici 2070 : les variations les
II
plus importantes seraient observées dans l’Extrême Nord, mais les endroits très peuplés de la province se réchaufferaient de 4 à 5 °C. Les
précipitations en saison de croissance ne devraient augmenter que légèrement (< 10 p. 100) dans la plus grande partie de l’Ontario, mais
diminuer dans le Sud et le Nord-Ouest de la province. Les hausses de température estivale prévues combinées à une augmentation faible ou
nulle des précipitations rendraient les sécheresses plus fréquentes et plus graves du fait d’une évapotranspiration accrue.
L’une des conséquences prévisibles de cet « assèchement » des forêts est l’expansion de la supericie de forêts brûlées, qui pourrait doubler
dans certaines parties de la province où la suppression des incendies n’est pas pratiquée. Par contre, dans les forêts gérées, habitées par un
plus grand nombre de personnes et utilisées de façon beaucoup plus importante pour la production de bois d’œuvre et les loisirs, la plupart des
incendies peuvent à l’heure actuelle être étouffés grâce à une intervention précoce. Cependant, lorsque les conditions météorologiques entraînent
un risque élevé d’incendie, l’intervention initiale peut présentement s’avérer infructueuse, et la fréquence de telles conditions augmentera
vraisemblablement en raison du réchauffement climatique. Par conséquent, un des effets attendus du changement climatique est la fréquence
accrue des incendies de forêt incontrôlables, ce qui entraînera des brûlis plus importants même dans les zones forestières gérées.
En raison de l’interaction complexe des arbres avec les insectes et les maladies, il est dificile de prévoir à quel moment se feront sentir
les effets du changement climatique sur ces perturbations et l’ampleur qu’ils prendront. Toutefois, les arbres affaiblis par la sécheresse seront
probablement plus vulnérables aux insectes et aux épidémies. Outre la sécheresse, les phénomènes météorologiques extrêmes tels que les
tempêtes de vent, les inondations et les vagues de chaleur pourraient nuire aux plantes et favoriser les invasions d’insectes et les épidémies. Par
conséquent, la plupart des maladies importantes qui affectent les arbres de l’Ontario devraient se manifester plus souvent ou, à tout le moins,
ne diminuer aucunement. Les hivers froids qui, traditionnellement, protégeaient l’Ontario de certains insectes se feront de plus en plus rares, et
n’empêcheront plus ceux-ci d’étendre leur territoire de répartition. Par exemple, le dendroctone du pin ponderosa, que l’on trouve depuis peu
d’années dans les forêts boréales du Nord de l’Alberta, risque d’envahir les pinèdes de l’Ontario avant 2050.
À mesure que le climat se réchauffera, les espèces et les peuplements indigènes d’essences forestières deviendront de moins en moins
bien adaptés à leur environnement naturel. Pour certaines espèces, cela se traduira par une croissance réduite au centre de leur territoire de
répartition et accrue à l’extrémité nord de celui-ci. Parce qu’ils vivent longtemps et suivent une lente migration naturelle, les arbres seront de plus
en plus mal adaptés à leur milieu et les procédés naturels ne parviendront pas à en déplacer les semences aussi rapidement qu’il le faudrait pour
suivre le rythme du changement climatique. Les aménagistes forestiers envisageront de plus en plus de planter des essences et des peuplements
non indigènes. De telles adaptations ne pourront toutefois être décidées sans qu’il soit tenu compte de leurs conséquences négatives possibles et
devront être documentées et surveillées étroitement.
Pour les forêts, les risques associés à la mise en œuvre de stratégies d’adaptation devront être comparés à l’incidence que les
mesures choisies pourraient avoir sur la biodiversité actuelle des espèces. C’est pourquoi une approche scientiique coordonnée
en matière d’adaptation des forêts peut aider les aménagistes forestiers à déterminer les stratégies possibles permettant d’atténuer
les effets négatifs du changement climatique. Le présent rapport décrit une approche appelée « adaptation judicieuse », selon
laquelle le risque de dommage lié à la mise en œuvre d’une adaptation est comparé au risque qu’entraînerait l’inaction. Les
adaptations présentant un risque élevé devraient ainsi être appuyées par des preuves démontrant hors de tout doute que l’absence
d’intervention poserait une menace imminente. Dans le cas des stratégies à faible risque, une documentation des résultats serait
exigée pour permettre une compréhension accrue des avantages et des inconvénients de l’adaptation. L’adaptation judicieuse
comporte des similitudes avec la gestion adaptative, les exigences de planiication et de surveillance étant les mêmes dans les
deux cas.
Selon le GIEC, une gestion forestière durable qui maintient les stocks de carbone forestier et procure un rendement soutenu en
matière de produits du bois constitue la meilleure stratégie à long terme d’atténuation du changement climatique pour les forêts.
Les produits du bois des forêts emmagasinent le carbone, mais peuvent également réduire les émissions de gaz à effet de serre
provenant des combustibles fossiles s’ils sont substitués à ceux-ci comme source d’énergie (en brûlant directement le bois ou en
brûlant le méthane généré par les produits du bois enfouis dans les décharges). Les produits en bois massif ayant une intensité
énergétique beaucoup plus faible que les matériaux de construction tels que l’acier, l’aluminium, la brique et le béton, la substitution
de ces matériaux par le bois réduit les émissions de gaz à effet de serre et représente une façon indirecte dont les forêts peuvent
contribuer à modérer le changement climatique.
Les forêts sont présentement gérées en fonction d’un paradigme de climat constant, qui suppose implicitement que le climat
demeurera inchangé. Puisque de nombreuses décisions prises aujourd’hui en matière de foresterie auront une incidence sur les
forêts dans 50 ans et plus, une transition vers des politiques et des pratiques qui reconnaissent les effets potentiels du changement
climatique s’impose. Pour permettre l’élaboration de telles politiques et pratiques, les chercheurs doivent répondre aux besoins de
la gestion forestière pratique en améliorant notre connaissance de la réaction des forêts à leur environnement et en concevant des
modèles qui utilisent ces renseignements pour prévoir l’état futur des forêts selon diverses conditions climatiques possibles.
III
Contents
Summary ................................................................................................................................ i
Resumé .................................................................................................................................. i
The Changing Climate ..........................................................................................................1
Climate Change in Ontario ...............................................................................................2
Forest Management and Climate .....................................................................................4
Climate and Natural Forest Disturbances..............................................................................6
Forest Fire .......................................................................................................................6
Insect Outbreaks .............................................................................................................6
Disease ............................................................................................................................7
Responses of Forest Vegetation to Climate Change.............................................................8
Forest Growth ..................................................................................................................9
Species Composition .....................................................................................................10
Silviculture in a Changing Climate .......................................................................................12
Harvest Rates................................................................................................................12
Wood Supply .................................................................................................................13
Genetics and Regeneration ..........................................................................................13
Carbon-Based Forest Management .............................................................................15
Conclusions .........................................................................................................................16
References ..........................................................................................................................18
IV
Acknowledgements
I appreciate reviews of the technical content of this paper by Dr. Paul Gray and Dr. Bill Parker, Science and
Information Resources Division, Ontario Ministry of Natural Resources. R.A. Lautenschlager also provided a technical
review of an earlier version of this paper. My thanks are also extended to the helpful staff of the Technology Transfer
department of the Ontario Forest Research Institute, including: Abby Obenchain who provided numerous helpful
suggestions in her review of style and grammar that greatly improved the readability of the manuscript; Trudy Vaittinen
for desktop publishing, Sarah Mislan who veriied references, and Lisa Buse for managing the publication process.
Funding for this project was through the Ontario Ministry of Natural Resources Climate Change Project number
CC-06-07-005.
CLIMATE CHANGE RESEARCH REPORT CCRR-12
The Changing Climate
Through industrial activity and tropical deforestation, humanity is on a path to emit enough greenhouse gas into
the atmosphere to cause the planet to warm to temperatures not seen in the past 100,000 years (Figure 1, IPCC
2007a). Although Earth has experienced similar amounts of natural warming in the distant past, the rate of these
past warmings has been much, much slower (Figure 1). No area of the planet and no plant or animal will avoid the
effects of climate change. That humanity could be rapidly changing future global climate sounds like science iction,
but scientists assert that this change will occur unless greenhouse gas emissions and tropical deforestation are
reduced (IPCC 2007a).
Under this scenario of rapid ecological change, natural resource managers must determine what the
impacts could be and how best to manage. Will trees grow faster or slower? Will wildlife species migrate north
as temperatures warm? Will warmer temperatures cause more forest ires? Such questions are important to
understanding how to manage forests sustainably today when the risk is high that the future climate may be very
different.
The International Panel on Climate Change (IPCC) predicts that the greenhouse gases expected to enter the
atmosphere will cause the average temperature of northern North America to increase by 1.4ºC-5.8ºC this century
(IPCC 2007a). The lower end of this range, a 1-2oC increase in global temperature, might not seem alarming, since
in the course of every day we see far greater changes in temperature. Even a 5-6oC increase in temperature may
not seem signiicant. However, a 1-2oC increase is an average for the entire planet, and changes in temperature in
some areas and at some times of the year will be much greater than the average global change. This means that at
high latitudes and during winter, temperatures will warm more than at low latitudes and during summer. In addition,
extreme events are expected to increase, as higher temperatures indicate more energy is in the atmosphere. As a
result, more loods will occur due to more intense rainfall, more windstorms, and more tornadoes (IPCC 2007a).
The rate of temperature change from human-caused global warming will be much greater than has occurred
over the past 400,000 years. The circled area of the left graph in Figure 1, for example, shows a large temperature
increase that occurred between 100,000 and 150,000 years ago, when global average temperature increased by
about 3.3oC over 2,400 years. At current rates of greenhouse gas emissions, Earth will experience at least this
increase in global temperatures, but the change will happen over only about 75 years.
Figure 1. Historical trends in annual global average temperature on a geological and recent time scale. The y-axis scale of the right graph
is from -0.5oC to +0.5oC, while the left graph has a y-axis scale 16 times as large, ranging from -12oC to +4oC. The periodic warming
shown in the left graph occurs over thousands of years, while recent warming shown at the right occurs over tens of years. The circled
portion of the left graph shows warming of about 4oC over about 2,400 years. (From: NEP/GRID-Arendal, Historical trends in carbon
dioxide concentrations and temperature, on a geological and recent time scale, UNEP/GRID-Arendal Maps and Graphics Library, June 2007,
<http://maps.grida.no/go/graphic/historical-trends-in-carbon-dioxide-concentrations-and-temperature-on-a-geological-and-recent-time-scale>
[Accessed 17 December 2007]).
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CLIMATE CHANGE RESEARCH REPORT CCRR-12
Climate Change in Ontario
The Ontario Ministry of Natural Resources (MNR) and Natural Resources Canada produced a publication
containing maps based on climate simulations from the Canadian Global Climate Model (GCM) for 2 intermediate
scenarios of future climate (A2 and B2) based on differing amounts of greenhouse gas emissions (Colombo et al.
2007b). The CD accompanying the report provides about 800 maps, showing Ontario climate at different times and
geographic scales (province, MNR administrative region, and MNR district). In Figures 2-4 here, we show maps
from Colombo et al. (2007b) of average summer temperature, average winter temperature, and total warm season
precipitation (April-September) projections for the period 2071-2100, based on the A2 scenario.
Across the province, warming is projected to be greater in winter than summer and greater in the north than the
south (igures 2 and 3). In the Far North, including the communities of Fort Severn, Kashechwan, and Sandy Lake,
summer temperatures are projected to increase 5-6oC. In much of the rest of Ontario, summer temperature will
increase 4-5oC. In 2071-2100, Kenora summer temperatures will be similar to those of present-day Windsor, while
Windsor will experience summers about as hot as present-day Virginia.
Under the A2 scenario, winters for people living near Hudson Bay are projected to be 9-10oC warmer by 2071,
and most of northern Ontario will warm by 6oC or more (Figure 3). This means people in northern parts of the
region will experience winter temperatures comparable to those hundreds of kilometres further south in 1971-2000.
For example, by 2070 winter temperatures:
• In Thunder Bay will be more like those in Peterborough
• The area running from Sault Ste. Marie east to Espanola and North Bay will warm 4-5oC (Figure 3)
• In most of southern Ontario, will warm 4-5oC (cities such as Barrie, Brockville, and Parry Sound will have mild
winters like those of Windsor today)
• In the already-mild Golden Horseshoe, plus Sarnia and Chatham, winters will be more like those currently in
southern Ohio and Indiana.
Precipitation is projected to change as well. By about 2011, precipitation in much of northwestern Ontario is
projected to decrease by up to 10%. By 2071 in an A2 world, almost the entire western half of northwestern Ontario
and much of southern Ontario will receive up to 10% less precipitation (Figure 4).This change, along with higher
temperatures, will result in considerably drier soils and forests. Under this scenario, most of northern Ontario is
projected to receive about the same or slightly higher precipitation in 2071, but even in these areas soils will be
considerably drier due to higher temperatures.
In addition to changes in climate, at current rates of greenhouse gas emissions, the concentration of CO2 in the
atmosphere will more than double by mid-century and triple by the end of the century from a pre-industrial level
of about 280 ppm. The last time the atmosphere contained over 500 ppmv CO2 is estimated to have been about
50 million years ago, and CO2 levels of 800 ppm have not been found on Earth since between 75 million and 100
million years ago (Fletcher et al. 2008). Carbon dioxide is the chief culprit in anthropogenic climate change and
the primary food source for plants. Changes in atmospheric CO2 levels directly affect photosynthesis and therefore
plant growth rates, water and nutrient use, competitiveness, and stress resistance. Under increased CO2 all
species will be more resistant to drought and, given adequate moisture and nutrient supply, will likely grow more
quickly; however, it is unclear how interactions among species will change and how insect herbivores will respond
(Mousseau and Saugier 1992, Karnosky 2003, Körner 2006).
CLIMATE CHANGE RESEARCH REPORT CCRR-12
Figure 2. Average summer temperature in Ontario from 1971-2000 (left) and projected increases in summer temperature in 20712100 (right), based on the Canadian Global Climate Model and the A2 greenhouse gas scenario (Colombo et al. 2007b). Numbers on
maps refer to temperatures (oC) in the case of 1971-2000 and increases in temperature (oC warming) in the case of 2071-2100.
Figure 3. Average winter temperature in Ontario from 1971-2000 (left) and projected increases in winter temperature in 2071-2100
(right), based on the Canadian Global Climate Model and the A2 greenhouse gas scenario (Colombo et al. 2007b). Numbers on maps
refer to temperatures (oC) in the case of 1971-2000 and increase in temperature (oC warming) in the case of 2071-2100.
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CLIMATE CHANGE RESEARCH REPORT CCRR-12
Figure 4. Total warm season precipitation in Ontario from 1971-2000 (left) and projected changes in warm season precipitation in
2071-2100 (right), based on the Canadian Global Climate Model and the A2 greenhouse gas scenario. Numbers on maps of 19712000 precipitation refer to millimetres of total precipitation received April-September; scale values for 2071-2100 are the percent
change in total warm season precipitation compared with 1971-2000 (Colombo et al. 2007b).
Forest Management and Climate
Many researchers are already seeing the effects of climate change (Parmesan 2006). In all well-studied
ecosystems (terrestrial, marine, freshwater), changes in the timing of temperature-driven events (such as bud
burst, lowering, breaking hibernation, migration, breeding) and the distributions of plant and animal species
are heading in the direction that climate change experts predicted (Parmesan 2006). In 2006, 10 eminent forest
scientists from the United States, Russia, and Canada found substantial evidence that boreal forests are already
responding to climate change (Soja et al. 2007). There are two important implications from their conclusions.
The irst is that although change in boreal climate has to now been slight, the response is readily observable,
suggesting that the boreal forest is relatively sensitive to climate change. The second implication is that with
comparatively large changes in climate in coming decades, the response may be more substantial than previously
projected.
Two recent surveys of forestry professionals have shown that most recognize the serious effects climate
change could cause and the need to adapt (Williamson et al. 2005, Colombo 2006). Even so, forest management
decision-making is still based on the assumption of a stable climate, whether the issue is where to plant what
species, which genetic sources to use, and how much to harvest, which is based on how quickly forests have
grown in the past. If forestry professionals’ attitudes have changed, why hasn’t forest management decisionmaking? Some possible reasons include:
1. Much forest management knowledge in use today is based on past behaviour of forests, which is not
correlated with climate and therefore is dificult to extrapolate to new climate conditions.
2. It is not certain how quickly and how much the temperature will increase and whether growing season
precipitation will be adequate.
3. Information is lacking about how forests respond to climate, including growth rates of trees and sensitivity of
forest succession.
4. The lack of climate change policies may be creating uncertainty about the acceptability of implementing
adaptations.
CLIMATE CHANGE RESEARCH REPORT CCRR-12
Uncertainty about future climate and forests’ potential responses to climate change mean that adapting to
climate change should be done with care, as such actions carry risks. However, given how quickly climate change
may occur, delaying action is also risky.
More than 40 years ago, U.S. Forest Service pathologist George Hepting acknowledged the need to adapt
to climate change and described how global climate change might affect forests and forestry in North America
(Hepting 1963). Over the intervening decades, forest research has not suficiently addressed climate change
impacts and adaptation to provide forest managers tools to allow them to plan to adapt. While exceptions exist,
research on climate change impacts on forests has been conducted mostly in the past decade. As a result, we still
have much to learn about adapting forests to climate change.
McLachlan et al. (2007) have developed a framework for assisted migration, which I have applied to the more
general issue of adapting to climate change. They identiied three positions that demonstrate the contrasting risks
of acting vs. not acting on adaptation: aggressive adaptation, adaptation avoidance, and judicious adaptation.
Aggressive adaptation is based on the concern that climate change presents an immediate threat to
ecosystems. Supporters of aggressive adaptation assume that climate is critical to ecosystem behaviour,
projections of climate change impacts on forests are accurate, and forests will not naturally adapt to avoid severe
climate change effects. They also believe that time to implement adaptation is short and that it is not possible to
predict all impacts on all ecosystems. Management strategies include moving species well beyond native ranges
and shortening harvest cycles to remove stands considered at risk of decline and whose regeneration presents
an opportunity for adaptation. This policy may be the preferred option to avoid harmful effects on forests due to
devastating and rapid climate change, but it could place existing forest values at higher risk of disruption.
In contrast, advocates of adaptation avoidance believe that human interference could have unintended
consequences in natural systems, given the great uncertainty in ecological understanding of climate-forest
interactions. The lag between implementing a new strategy and potential negative effects can sometimes be
decades long, so monitoring negative impacts may be impractical. Proponents of adaptation avoidance are
motivated by the high uncertainty about future climate projections and the similar if not greater uncertainty about
ecosystem responses to climate change. Avoiding adaptation could greatly increase the risk of severe climate
change impacts on forests. Where active adaptation is avoided, forest managers should encourage policies that
facilitate adaptation by natural processes. For example, they could allow natural disturbance to increase or rely
more on the intense selection pressure from natural regeneration by seed, instead of planting trees from local seed.
The third strategy outlined by McLachlan et al. (2007), judicious adaptation, balances risks from unrestrained
adaptation and adaptation avoidance. It is based on the belief that some (but not all) adaptation actions are
warranted despite their risks. In a judicious framework, risk is reduced by restricting what actions can be taken,
carefully planning their implementation, and closely monitoring their results. This planning-monitoring approach has
similarity to adaptive forest management. One approach would be to consider potential actions using a framework
for incorporating climate change adaptation in forest management, such as the one developed by Ogden and Innes
(2007). Speciic adaptation options could be developed by multi-disciplinary panels of local experts and scientists
(McLachlan et al. 2007) and prioritized in terms of risk (high, moderate, low) and geographic scale (large, medium,
small).
Presumably, climate change adaptation proposals carrying high risk would require a strong case showing the
need to act promptly to avoid an imminent threat. The potential spread of mountain pine beetle into northwestern
Ontario is an example of a threat that could cause forest managers to consider implementing a relatively high
risk adaptation strategy. To consider acting on even moderate-risk proposals would require strong evidence
of beneit and even stronger evidence of risks of inaction. Decisions would be made by balancing respect for
the precautionary principle and the need for pilot projects to improve understanding of the risks and beneits of
implementing adaptations. This cautious approach would likely be relaxed as uncertainty about future atmospheric
greenhouse gas levels is reduced; improvements in GCMs reduce the uncertainty of global climate projections;
forest scientists provide better tools to predict the outcomes of adaptation; and forest managers gain experience
with implementing adaptations.
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Climate and Natural Forest Disturbances
Increased frequency, intensity, and geographic extent of natural disturbance are expected to be some of the
most obvious and immediate effects of climate change on forests (Pollard 1989, Flannigan et al. 2005). Insects
and diseases are sensitive to climate and should provide some of the earliest visible impacts of climate change
(Pollard 1989). The massive outbreak of mountain pine beetle in western Canada is a prime example of how
warmer winters can favour insect pests. Pests and disease also increase fuel loads, indirectly increasing the area
burned by forest ires (Pollard 1989).
Forest Fire
Predictions of how climate change may alter ire frequency, intensity, and area burned is based in part on
empirical relationships between past climate and ire disturbance (e.g., Flannigan and Harrington 1988). Altered
precipitation and temperature across North America will change ire risk, with some areas experiencing greater
risk and other areas less (Flannigan et al. 2000, Dale et al. 2001). Climate warming is expected to increase the
length of Ontario’s ire season in Ontario by up to 16% or 25 days (Wotton and Flannigan 1993). Higher summer
temperatures increase evaporation and transpiration and dry out forest soils, dead trees, and downed wood.
These changes increase the risk of forest ire, even when precipitation does not decrease.
Future ire risk was projected by Flannigan et al. (2000) using 2 GCMs and a seasonal ire weather severity
rating model. Higher seasonal severity ratings yield greater area burned. With a doubling of CO2, the Canadian
GCM projects an increase >30% in the average seasonal severity rating for the southeast United States and
Alaska and most of Canada north of the 48th parallel (Flannigan et al. 2000). This model also predicts increased
seasonal severity rating of 40% or more in much of northwestern Ontario and northern Manitoba. According to
both the Canadian and Hadley GCMs, a tripling of CO2 later in the 21st century would increase area burned in
Ontario’s forests by 1.5 to more than 2.0 times, with greater increases in more northerly parts of the province
(Flannigan et al. 2005). Large ires tend to be uncontrollable, and large ires will increase under climate change
(McAlpine 1998).
Present-day area burned in Ontario’s managed forest is relatively low, relecting high initial ire attack success
rates (Ward et al. 2001). However, more severe ire weather may create ire spread conditions making initial attack
less successful (Flannigan et al. 2005) and result in more large burns. Large increases in forest area burned
would change biodiversity to relect more ire-origin stands and younger average forest age (Weber and Flannigan
1997).
Insect Outbreaks
Predicting how climate change might affect forest insect infestations is dificult because insect populations
depend on relationships with hosts, competitors, predators, and symbiotes (Williams et al. 2000). For this reason,
modelling is often used to describe the effects of climate change on insect populations. Direct effects of climate
change on insect herbivores will be through insect growth, development, and reproduction (Williams et al.
2000). Since many insects can produce multiple generations in a year, even a small increase in growing season
temperature could add a generation, increasing the potential for damage to trees (Williams et al. 2000). Climate
change can also affect insects indirectly by altering host plant physiology and predator behaviour (Williams et al.
2000).
Fleming and Candau (1998) predicted that disturbance patterns of insects whose distributions depend largely
on climate will likely change greatly under projected climate warming. Northern range limits for many insect
herbivores are based on their ability to survive low winter temperatures; as the climate warms, ranges should
move northward (Parker et al. 2000, Williams et al. 2000).
Pollard (1989) predicted the extremely high risk of an outbreak of mountain pine beetle (Dendroctonus
ponderosae) in British Columbia, and the recent extensive outbreaks of mountain pine beetle in British Columbia
are attributed to milder winter temperatures (Pollard 1989, Dale et al. 2001). Cumulative lodgepole pine (Pinus
CLIMATE CHANGE RESEARCH REPORT CCRR-12
contorta Dougl.) mortality in British Columbia’s timber harvesting land base from 1998 to 2006 was approximately
530 million m3, representing 40% of the total merchantable volume of pine, and by 2014, nearly 80% of the
province’s lodgepole pine may be killed (Walton et al. 2007). The outbreak has spread extensively in northern
Alberta’s boreal forest, with aerial recognition of affected stands as far east as Swan Hills (http://www.srd.gov.ab.ca/
forests/health/conditionsmaps/mpbcurrentmaps.aspx, viewed December 21, 2007). The mountain pine beetle is
also favoured by higher summer temperatures and moisture stress, conditions projected to become more common
in boreal forests in Saskatchewan, Manitoba, and northwestern Ontario. Thus, it is now likely a question of when
the mountain pine beetle will migrate into Ontario, not if migration will occur (Logan and Powell 2001, Logan et al.
2003). Logan and Powell (2001) projected migration of mountain pine beetle to Ontario by 2050. The rapid spread
of this beetle east into Alberta may indicate that it could reach Ontario much sooner than projected.
Climate change can affect defoliating insects that feed on newly expanding leaves, since they need to hatch
when bud burst occurs. Warmer spring temperatures in Europe have reduced defoliation of English oak (Quercus
robur L.) as the hatching of the winter moth (Operophtera brumata L.) is no longer tightly synchronized with
bud burst (Visser and Holleman 2001). In addition, drought can delay budburst (Colombo, unpublished) and
thus cause insects to hatch before the optimum time for feeding. Even a few days difference in the timing of
caterpillar emergence or new shoot elongation can cause insects to starve (Williams et al. 2000). In the same
way, asynchrony of parasitoids with their insect hosts, which provide some natural control of pest insect levels,
may increase or decrease as the climate changes (parasitoids are insects whose larvae develop within or on other
insects, eventually killing the host).
Williams et al. (2000) speculate how climate change may affect the major insect pests of trees in the northern
United States. Warmer wetter summers would favour vigorous shoot growth of white pine (Pinus strobus L.), which
in turn would favour the white pine weevil (Pissoides strobi Peck). Increased water stress would favour the spruce
beetle (Dendroctonus ruipennis Kirby) and in a warmer climate could complete its life cycle in 1 year rather than
2. Warmer temperatures may also allow the hemlock woolly aphid (Adelges tsugae Annand) to produce another
generation annually, to survive better during milder winters, to begin activity earlier in the spring, and to spread
further north (Williams et al. 2000). Fleming and Candau (1998) conclude that while climate change will likely alter
the severity of spruce budworm (Choristoneura fumiferana Clem.) outbreaks, predicting the likelihood of such
changes remains dificult.
Disease
Geographic patterns of most historical disease outbreaks are poorly understood. Exceptions occur when alien
diseases affect native tree species, causing relatively rapid and extensive losses of prominent species, such as
Dutch elm disease (Ophiostoma ulmi (Buisman) Nannf.) and chestnut blight (Cryphonectria parasitica (Murrill) M.E.
Barr). Losses caused by most native diseases are usually dificult to identify, as they tend to affect scattered trees
or pockets of trees, and even foresters ind it dificult to relate mortality to disease. As a result, climate-disease
interactions are often unclear, and disease effects often go unrecognized.
Disease occurs when interactions among host, pathogen, and environment favour the pathogen (Williams et al.
2000). In general, where climate change increases tree stress in the presence of a pathogen, disease increases.
Trees growing in marginal environments may be more susceptible to disease if climate change increases
environmental stress (Coakley et al. 1999). Trees now exposed to intermittent summer drought because they are in
dry habitats may be more prone to disease if climate change further reduces soil moisture. For example, Armillaria
spp. root rot may increase where drought becomes more common (Coakley et al. 1999, Williams et al. 2000), and
heat stress may boost the occurrence of Scleroderris canker (Gremmeniella abietina (Lagerb.) M. Moreleton) on
pine (Coakley et al. 1999).
On the other hand, some species may experience less disease if environmental stress is reduced (e.g., trees
growing near their northern limit that often experience freezing stress may beneit from a warming climate).
Increased temperature extremes and droughts, rather than changes in average temperature or precipitation, are
likely to favour diseases (Boland et al. 2004), with disease becoming evident sometimes long after the stress.
Latent pathogens (parasitic disease organisms that can lay dormant until a tree becomes stressed) may kill
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individuals weakened by drought (Desprez-Loustau et al. 2006). Increased drought, a possible outcome of climate
change for some parts of Ontario (Colombo et al. 2007b), could contribute to “decline” diseases in tree species.
Whether diseases expand into new regions is determined by their method of dispersal, the suitability of the
environment (especially winter weather), and host species physiology (Coakley et al. 1999). Climate matching
models (e.g., BIOCLIM, CLIMEX, HABITAT, and WORLD) have been used to predict changes in pathogen ranges
based on future climate (Williams et al. 2000). Generally, wetter conditions increase the incidence and severity of
foliar and root pathogens that depend on higher moisture levels to develop and disperse (Williams et al. 2000).
Seem et al. (2000) developed a model predicting surface wetness duration, a critical factor in the spread of many
diseases, including white pine blister rust (Cronartium ribicola J.C Fischer). Applying such a model to Ontario could
allow susceptibility of white pine to blister rust to be projected with future climate change.
Elevated winter temperatures will increase the spread of dormant season pathogens, such as stem canker
fungi, whose growth is limited by winter cold. Snow moulds, requiring humid but not extreme cold under snowcover,
may increase in some areas but decrease where snowfall decreases (Williams et al. 2000). Boland et al. (2004)
summarized the potential effects of climate change on tree diseases in Ontario. They project that climate change
will increase the incidence of decline diseases of maple, oak and ash; beech bark disease (Nectria coccinea
(Pres.:Fr.)Fr. var. faginata Lohman, Watson & Ayers); oak wilt (Ceratocystis fagacearum (Bretz) Hunt); Armillaria
root rot (Armillaria ostoyae (Romagn.) Herink); blue stains; Diplodia canker; Fomes root rot (Heterobasidion
annosum (Fr.:Fr.) Bref.); Hypoxylon canker; and Tomentosus root rot (Inonotus tomentosus (Fr.: Fr.) Teng). They do
not expect any tree disease in Ontario to decline with climate change.
Hurricanes can rapidly spread insects and insect-borne diseases, and they are expected to increase under
climate change (Dale et al. 2001). In the early 1950s, hurricanes may have helped spread elm bark beetles into
eastern Canada (Hepting 1963). The rapid and long-scale movement of insect-borne diseases by hurricanes,
combined with forests’ increasing environmental stress, could result in large and unpredicted outbreaks of exotic
insects and diseases.
Responses of Forest Vegetation to Climate Change
Forest species composition and growth, respectively elements of forest structure and forest function, are
sensitive to climate. Climate affects forest growth rates in large part through growing season length, availability
of soil moisture, and temperatures at which photosynthesis and respiration take place. In comparison, species
composition responds to climate by effects on survival of existing trees in mature stands, lowering and seed
production, and survival of germinated seedlings. However, the long time between stand establishment and
replacement of most northern tree species means they will be increasingly less well adapted to local conditions as
climate change progresses (Aitken and Hannerz 2001).
Potential climatic disequilibrium of species with environment can be evaluated using climate envelopes (e.g.,
Shafer et al. 2001, McKenney et al. 2007). With this approach, the current climate in which a species grows
is described in terms of climate values such as summer or winter temperature, growing season precipitation,
and growing degree days. The future location of a species’ climate envelope after a period of climate change is
then compared with the present one. McKenney et al. (2007) found that the major changes in climate predicted
for coming decades could result in many North American trees growing outside their climate envelopes. Other
researchers have found similar results: In most cases species’climate envelopes are projected to move north and
to move mostly or entirely beyond the current range (e.g., Iverson and Prasad 2002, Iverson et al. 2005, Malcolm et
al. 2005, McKenney et al. 2007).
Even the lower ranges of predicted warming and drying could affect the composition and productivity of forests,
such as in northern Michigan, where such changes could cause decline in several commercially valuable tree
species (Reed and Desanker 1992). According to Graham et al. (1990), increasing summer temperature in the
Great Lakes Region would move the present climatic envelope hundreds of kilometres north. The southern range
CLIMATE CHANGE RESEARCH REPORT CCRR-12
limits of sugar maple (Acer saccharum Marsh.), trembling aspen (Populus tremuloides Michx.), balsam ir (Abies
balsamea (L.) Mill.), white birch, white spruce (Picea glauca (Moench) Voss), black spruce, jack pine, and red
pine (Pinus resinosa Ait.) to the north is about halfway up the lower Michigan Peninsula, and in Ontario there is
a transition from these species along a line running across southwestern Ontario roughly from Grand Bend (near
Sarnia) to Toronto. South of this line, species such as silver maple (Acer saccharinum L.), shagbark hickory (Carya
ovata (Mill.) K.Koch), black walnut (Juglans nigra L.), yellow poplar (Liriodendron tulipifera L.), sycamore (Platanus
occidentalis L.), and black oak (Quercus velutina Lam.) are more common. As the climate warms, the fastergrowing, less cold-hardy species to the south of these lines in Michigan and Ontario could slowly migrate north,
each at a unique rate (Reed and Desanker 1992).
Changes in climate envelopes for western Upper Michigan are also expected to favour southerly species
within less than 100 years. Again, slow rates of natural migration mean these species will be unable to exploit
the potential new range (Solomon and Bartlein 1992). For example, the climate envelope for butternut (Juglans
cinerea L.) will move to western Upper Michigan within 70 years, but the nearest butternut are about 90 km
south. Based on historic migration rates, these butternut populations are about 450 migration years away. White
oak (Quercus alba L.) and black oak will be in a similar situation, with warming predicted to move their climate
envelopes into western Upper Michigan within 150 and 200 years, respectively, while these species would require
200 and 500 years, respectively, to migrate (Solomon and Bartlein 1992).
Most studies of climate envelope movement predict that tree migration will be slower than envelope movement
(Tallis 1991, Iverson et al. 2002, McLachlan et al. 2005). Movement of more southerly tree species into Ontario will
also be slowed by physical barriers such as the Great Lakes and the large areas of farms and cities in the United
States and southern Ontario, as well as the fact that populations of Carolinian species in southern Ontario are
small and isolated. Even existing forests can hinder migration, since many tree species do not regenerate under a
forest canopy.
Forest Growth
Each tree species is uniquely affected by responses to climate based on its ability to respond to increased (or
decreased) soil moisture and nutrient availability, and disturbance frequency. For example, Goldblum and Rigg
(2005) modelled the potential change in growth rates of 3 tree species − sugar maple, white spruce, and balsam
ir − at the margin of the Great Lakes-St. Lawrence and boreal forest regions in Ontario. Their results showed that
sugar maple will likely increase growth the most, with a smaller increase for white spruce. Balsam ir was projected
to have decreased growth.
Climate envelope movement can overestimate effects of climate change on growth of widely distributed
species. Trees from local seed sources are usually considered best adapted to local climate because their growth
cycle should be more attuned to climatic cues (Wright 1979). However, this principle may not always apply to
widely distributed species. For example, lodgepole pine populations near the northern species limit in British
Columbia grow at temperatures that are up to 7oC colder than is optimum for growth (Rehfeldt et al. 1999); growth
of these populations should increase with climate warming. However, nearer to the centre of its range, in southern
British Columbia, lodgepole pine populations it the “local is best” concept, growing in climates only 0.5oC below
their optimal temperature. Here climate warming will result in local populations being increasingly maladapted,
decreasing growth (Rehfeldt et al. 1999).
Where drought increases, competitiveness and growth rates of moisture-loving species could fall, favouring the
transition to more drought-resistant ones. However, elevated CO2, which increases drought resistance, will offset
drought effects of climate change to some extent. Occasional episodes of hot, dry conditions could lead to rapid
regional decline of some species (Parker et al. 2000) and increase the incidence of damaging disease and insect
infestations. Such an event occurred in the early 2000s, when pinyon pine (Pinus edulis Engelm.) in the U.S.
Southwest experienced extensive mortality over a 15-month period due to low soil moisture, which favoured a bark
beetle infestation (Breshears et al. 2005).
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Increasing atmospheric CO2 apart from changes in climate will affect growth in the short term and alter
species abundance and population genetic makeup. Early successional species (e.g., raspberry (Rubus) and
grasses) react more aggressively to disturbed areas and have a larger increase in growth under elevated CO2,
and their short life cycles allow more rapid genetic adaptation to changing climate (Körner 1993). More aggressive
competition may hinder regeneration of trees. Lindroth et al. (1993) found that trembling aspen, red oak (Quercus
rubra L.), and sugar maple, in that order, increased dry matter growth under elevated CO2, indicating the potential
for species’ competitive abilities to change as greenhouse emissions rise. Analysis of over 500 studies on the
effect of elevated CO2 on woody plant growth described large positive plant responses, ranging from a growth
reduction to a ive-times increase relative to plants grown at ambient CO2 levels (Curtis and Wang 1998); across
all the studies they assessed, biomass increased signiicantly at about double ambient CO2, with an average
increase of 31%.
Increased CO2 can also affect competitiveness within a species. For example, Houpis et al. (1999) found
that photosynthetic increases in ponderosa pine (Pinus ponderosa Laws.) populations varied from 19% to 49%.
However, in black spruce (Johnsen and Major 1998) and jack pine (Cantin et al. 1997), the most common conifers
in Ontario, CO2 increased growth of all populations but did not alter their relative rankings. In contrast, elevated
CO2 altered competitiveness among trembling aspen clones (Lindroth et al. 2001, Tupker et al. 2001).
Increasing temperature could favour growth of northern forests by increasing photosynthesis. However,
the extent of growth increases will depend on the mineralization of additional available nitrogen, which often
limits photosynthesis (Saxxe et al. 2001). Many models predict that climate change and increasing CO2 in the
atmosphere will increase global forest growth over the next 50-100 years, especially at higher latitudes. However,
increased rates of forest disturbance will reduce forest growing stock and offset gains from potential growth
increases (Saxxe et al. 2001).
Several large-scale analyses have focused on how climate change will affect forest productivity, including
Joyce and Nungesser (2000), who predicted forest productivity in the United States will increase under elevated
CO2. However, these researchers noted that where moisture stress or low nutrient availability occur, productivity
increases will be constrained. They projected changes in productivity using 2 global climate models (OSU, the
Oregon State University model and GFDL-Q, the Geophysical Fluid Dynamics Laboratory Q-lux model). Using
outputs from both GCMs, the effects of changes in temperature and precipitation projected under climate change
in 2044 with CO2 at 625 ppm are predicted to increase growth 20-40% in northeastern and Lake States forests in
the United States, near the southern border with Ontario.
In another U.S. study, Jenkins et al. (2000) used 2 forest productivity models to examine potential effects of
climate change. Climate change and elevated atmospheric CO2 were projected to cause “very large increases in
forest NPP” in the northeastern U.S. However, similar to Joyce and Nungesser (2000), actual gains will be more
modest because of limitations of forest soil nutrients, the effects of pollution by acid rain and ground-level ozone,
and, on some sites, water stress due to inadequate precipitation.
Species Composition
Many boreal species can survive in temperate climates (Loehle 1998), indicating that southern species limits
do not necessarily relate to maximum summer temperatures. Species distributions relect a tradeoff between
height growth rate and tolerance of cold temperatures (Loehle 1998). Thus, at southern range margins, most
species are not limited by high temperatures but are instead outcompeted by faster-growing species. At northern
range margins, the effects of temperature on lowering, seed set, and seedling survival may determine species
success rather than maximum winter frost resistance of leaves and buds (Bannister and Neuner 2001). Increasing
minimum winter temperatures will allow more southerly, faster-growing species to migrate north. As stated by
Loehle (1998): “The implication for future climate change is that forests will not suffer catastrophic dieback due to
increased temperatures but will be gradually replaced by faster-growing types, perhaps over hundreds of years.”
CLIMATE CHANGE RESEARCH REPORT CCRR-12
Changes in tree species composition on a landscape usually occur slowly, even though species composition at
a stand level can occur quickly following disturbance or over the course of several growing seasons in response
to drought or insects. One reason landscape-level changes are slow is that even in ire-prone parts of the boreal
forest the annual rate of forest disturbance may only be 1% per year, part of which would return to its predisturbance composition. A 1% disturbance rate means that after 30 years of altered climate, composition of the
remaining 70% of the forest would tend to be unaltered.
Following forest disturbance an opportunity exists for regeneration of a different mix of tree species than was
in the preceding stand. Under current climate, species regeneration success can depend on the ability to survive
high levels of environmental stress; climate change is liable to intensify stress from high temperatures and drought
producing inter-species and genetic pressure on regenerating trees and other plants. Seedlings occupy a narrow
physical zone just above the ground (Figure 5), where environmental conditions create selection pressures on
seedlings (Colombo 1996). Highest temperatures on sites disturbed by ire and harvest usually occur within a few
centimetres of the soil-air interface due to the soil absorbing heat from the sun (Geiger 1965). Temperatures usually
decline sharply to more moderate levels in the air above the surface and below ground. As trees grow, their buds
and foliage are no longer in this maximum heat zone, reducing stress. Therefore, heat stress will affect seedlings
more than older trees as climate change increases temperatures.
Desiccation is also a problem for young trees, which have small root systems tapping small soil volumes. Young
plants’ roots tend to reside exclusively in the upper horizons of the soil, the area that is usually driest and hosts the
most intense competition for water. As trees grow, much of the root system remains near the soil surface, but the
root system grows wider and usually deeper, increasing access to soil moisture and reducing the likelihood of water
deicits (Figure 5).
In addition to having limited root systems, seedlings inhabit the high temperature/high vapour pressure
saturation deicit zone just above the soil surface, increasing transpirational water loss and desiccation risk.
As trees grow, shoots extend up to cooler zones, where air drying is usually lower, reducing transpiration and
desiccation. Windiness is usually greater further above ground, which increases transpiration but also cools the
foliage. As the crown closes, windiness within the canopy drops, reducing drying.
Although climate change is likely to favour regeneration of more heat and drought tolerant species, regenerating
species can only come from those whose seeds or suckers (in the case of aspen) are able to reach the site of
forest disturbance. Seed dispersal distances for Ontario species provided by Burns and Honkala (1990) indicate
that the majority of seed for any tree species falls within <100 m of the parent tree. So, some mixture of the
species present near a forest disturbance is most likely to regenerate. Climate change may affect composition of
regenerating stands by altering lowering and seed production and by creating a hotter, drier seedling environment.
In contrast to stands affected by canopy-removing stand disturbance, some stands become overmature and
canopy gaps formed as older trees die are illed by shade tolerant trees from the understory. However, understory
temperatures are buffered by the remaining canopy and other understory vegetation. Consequently, this form of
forest succession provides less opportunity for natural adaptation to climate change to take place by selective
pressure on seedling survival, compared to strong selective pressure when seedlings regenerate disturbed sites.
In the case of non-disturbance forest succession, tree species and within-species genetic composition will lag
behind climate in what is termed vegetational inertia (Cole 1985, Lewin 1985), which can allow a plant community
to remain long after the climate the community was established in has changed (Lewin 1985). Unless affected by
a stand-replacing disturbance (Kullman 1989), such out-of-synch communities will tend to persist since dominant
species can exclude competitors and affect microenvironment (e.g., light, moisture, soil chemistry) to their favour.
The time lag for vegetational change depends on growth rate during reproduction of a potentially migrating species
compared with the resident species, the availability of seed and seedbed, and the difference between the prevailing
climate and a species’ climate envelope (Lewin 1985).
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Figure 5. Environmental stress exposure during tree establishment. Smaller plants occupy the air/soil interface where temperatures
and moisture luctuate most exposing them to water deicits, freezing, and high temperatures. (From Colombo 1996)
Silviculture in a Changing Climate
Disturbance by ire, insects, and disease will probably be the largest and most immediate effects of climate
change. Increased ire frequency in particular could affect silviculture by reducing average stand age and
wood availability and by creating opportunities for southern species to migrate naturally or to be introduced by
planting (i.e., assisted migration). In addition, Rehfeldt et al. (1999) concluded that “there seems little doubt
that maintaining forest productivity in the face of global warming would require human intervention to assist the
migration of genotypes to their most suitable climates.”
Harvest Rates
Climate change can affect harvest rates in at least 3 ways:
1. Maintaining a desired stand age distribution or total area of disturbance may require adjustment of ire and
forest management strategies if risk of natural disturbance changes.
2. Forests at high risk of loss to disturbance or general decline could be harvested before reaching their
otherwise optimal rotation age, allowing replacement by better-adapted species or populations and
permitting utilization and capture of carbon in forest products.
3. Salvage harvesting on disturbed areas may be considered to meet wood supply needs.
As climate change causes species and populations to be less well adapted to local conditions, disturbance
will provide an opportunity to plant better-adapted species and populations or to allow natural selection during
regeneration to favour more adaptable species. Disturbance in general can help forests adapt to a changing
climate, but stands at increased risk of forest ire, insect infestations, or disease could, in certain cases,
be harvested to allow the use of the wood. Such a strategy could be important to improve adaptedness of
commercial species with long harvest cycles, which will be increasingly at risk as climate change progresses
during their long life spans (Singh and Wheaton 1991).
CLIMATE CHANGE RESEARCH REPORT CCRR-12
Milder winters and increased freeze-thaw activity will likely create problems for winter forestry operations,
especially logging and hauling, in areas dependent on frozen ground and watercourses (Pollard 1989). Logging
and hauling could be shut down during the winter, or winter harvesting could be shortened due to later freeze-up
and earlier thawing. The response could be to construct more all-weather logging roads, which have a greater
ecological impact on forests than winter roads do and cost more (Pollard 1989).
Wood Supply
In Ontario and most other jurisdictions, growth of commercial forests is predicted by examining the historical
relationship between a species’ growth rate and tree age in a particular forest region or district. Merchantable
volumes are predicted using yield tables constructed from historical tree and stand growth data. However,
because trees live so long, size-based measurements relect the average growth response to past climate and
site conditions. Forests more than 150 years old regenerated during the colder conditions of the Little Ice Age
(Gillson and Willis 2004); thus, predictions of future forest growth based on historic growth will be increasingly
inaccurate as the climate changes.
Today’s forest managers need forest growth projections that incorporate the effects of climate change and
elevated CO2. Developing such predictions requires an approach that is not based on the premise of a static
environment and historical growth rates. One option is to use process-based, climatically driven growth and yield
models such as TRIPLEX, which account for changes in environment (Peng et al. 2002). With TRIPLEX, empirical
forest growth and yield models are modiied by combining them with data on environment (monthly mean
temperature, soil moisture availability, and length of the frost-free period), allowing them to produce wood supply
projections that are related to climate change scenarios.
Warming and longer growing seasons may make some forested areas with productive soils more suitable
for farming; converting these areas to farmland could decrease forest area, as could increased forest ire and
drought. Some parts of Northwestern Ontario, where forests may change from conifer- to aspen-dominated
stands or from aspen stands to aspen parkland or grassland (Hogg and Bernier 2005), are particularly at risk. At
the southern edge of the boreal forest of western interior Canada, where some species already regenerate with
some dificulty, intermittent forests may be reduced further (Singh and Wheaton 1991, Hogg and Bernier 2005).
Such changes in the amount of forested land would in turn affect wood supply.
Future silvicultural efforts should concentrate on forested sites likely to remain productive despite climate
change (Singh and Wheaton 1991). For example, fast-growing genotypes should be planted mainly in areas
not expected to experience frequent drought as the climate changes. Silvicultural practices that increase
water availability, such as thinning and competition control during regeneration (Parker et al. 2000), could be
encouraged if moisture stress is an issue, as could planting drought-tolerant species (Papadopol 2000).
Genetics and Regeneration
Species or provenances growing outside their climate envelope are more susceptible to competition,
predation, disease, and ire (Pollard 1989). In this way, natural forces tend to maintain better-adapted species and
populations (Pollard 1989). According to Hepting (1963), “if the probability of the relation of climatic inluences
to certain tree declines is appreciated by foresters…we are more likely to plan our silviculture to encourage or
to plant unaffected species or geographic races of the declining species that are better adapted to the newer
climate.”
To what extent should species or genotypes from more southerly sources be planted further north to better
match future climate conditions? Rehfeldt (2000) was of the opinion that to avoid large reductions in wood
production, forest managers will need to plant climatically adapted populations. Planting to transfer appropriate
genotypes between seed zones or introducing new species can accomplish climatic adaptation in one generation
what nature would need several generations to do (Singh and Wheaton 1991, Rehledt 2000).
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CLIMATE CHANGE RESEARCH REPORT CCRR-12
Planting nursery stock north of its current seed zone to try to match a future climate may or may not increase
future timber yields but can carry immediate risk from freezing damage (Ledig and Kitzmiller 1992, McLachlan et
al. 2007). Natural selection has resulted in shorter growing cycles to avoid damage from late spring and early fall
frosts. Thus, local populations do not take full advantage of the growing season in average years. Transferring
populations north will increase yields in future but at present risks exposing trees to freezing damage due to the
tendency of southern populations to remain active later in the growing season and to resume growth sooner.
Ledig and Kitzmiller (1992) suggested addressing this risk using the “diversity principle”: by planting local seed
sources mixed with some expected to be better adapted to climate change. The relative amounts of each seed
source in the mixture would depend on the degree of certainty of projected climate changes.
The other problem with moving seed sources northward is they may not be matched to local daylength (Ledig
and Kitzmiller 1992). The longer photoperiods during the growing season at more northerly latitudes could cause
trees to remain active later, making them more susceptible to fall frosts. Ledig and Kitzmiller (1992) suggest
that photoperiod might not be a factor if moving seed 150 to 300 km northward. However, Singh and Wheaton
(1991) suggest that each 1oC increase in temperature in North America will translate into a range change of 100
to 150 km. Based on the A2 scenario and the Canadian GCM, by mid-century most of Ontario is projected to
experience average temperature increases of 3-5oC in summer and 5-8oC in winter (Colombo et al. 2007b). Thus,
to match temperature seed would need to be moved 400 to 600 km north, but this would result in mismatching of
populations with photoperiod.
Ensuring genetic diversity of planted forests will be important to allow species to adapt to their new
environment and be able to perform moderately well in a range of conditions. Climate and atmospheric CO2 will
likely change beyond the end of this century, and the nature of change over even the next several decades is
uncertain. In addition, forest managers must be prepared to plant at higher than historic rates, to assist the slow
natural redistribution of genotypes (Rehfeldt 2000).
Forest managers often rely on natural regeneration to produce new forests after disturbance. For example,
much of the area burned by forest ire regenerates readily from seed or sprouts of local origin. However, if climate
change means local populations are no longer optimal, then increased planting might be used to introduce
better-adapted populations. Given the predicted speed of climate change, artiicial regeneration will be needed
to grow new forests where they are climatically well adapted (Rehfeldt 2000). Seed collection efforts will need to
increase to support increased planting (Cherry 2001), especially for species with seed that does not store well.
Species will vary in how much help they will need to adapt to new climate conditions (Parker et al. 1999). Widely
distributed species, which are usually more genetically diverse, should adapt to some extent through natural
selection. However, adaptation pressure is greatest during regeneration (Figure 5; Colombo 1996). Therefore,
even widely distributed species may require intervention through planting selected genetic sources in new areas
and conserving and propagating genotypes adapted to potential future climates (Rehfeldt 2000).
Rehfeldt (2000) pointed out that deciding how to renew forests under climate change is complicated by the
need to adjust not only what to do but also when to begin doing it. He argues that it is not too early to begin
adjusting seed deployment by transferring genotypes from warmer provenances to cooler ones. A simpler
approach might be to mix seed from different zones and to allow natural selection to take place (Ledig and
Kitzmiller 1992, Rehfeldt 2000). As already noted, assisted migration of genotypes and species according to
climate change predictions should relect social, technical, and scientiic input. Foresters should begin soon to
develop scenarios for allocating nursery stock that will allow them to deploy provenances and species based
on projected rather than historical climate zones. However, they must recognize the risks of acting on such
scenarios, especially if contemplating introducing non-native species. Before planting nursery stock outside their
current climate zones, a key step would be to ensure such movement is based on peer-reviewed science. One
means of doing so is to submit proposals to an expert panel with a mandate of respecting the precautionary
principle while permitting pilot projects that improve understanding of the risks and beneits of implementing
adaptations (McLachlan et al. 2007).
CLIMATE CHANGE RESEARCH REPORT CCRR-12
Carbon-based Forest Management
In 2007, the Fourth Assessment Report by the IPCC stated that “in the long term, a sustainable forest
management strategy aimed at maintaining or increasing forest carbon stocks, while producing an annual sustained
yield of timber, ibre, or energy from the forest, will generate the largest sustained mitigation beneit” (IPCC 2007b,
Chapter 9, Page 543.).
Some forest activities increase carbon storage, while others release carbon to the atmosphere or are carbon
neutral. Deforestation caused by forest access roads, for example, releases carbon to the atmosphere from the
increased decomposition of organic matter removed to construct the road, and more important, from reduced
carbon sequestration by creating areas that no longer grow trees (Colombo et al. 2005). In contrast, planting
increases carbon sequestration compared to natural regeneration from seed, if it allows faster establishment of tree
cover and greater likelihood of full stocking. Carbon in forests must be considered in context with net greenhouse
gas exchange with the atmosphere, including emissions from forestry activities, carbon stored in wood products,
and avoided emissions when wood products are used in place of more energy-intensive alternative fuels or
materials. Overall, harvesting forests at a rate that maintains the standing forest stock, combined with an increasing
stock of wood products, results in net removal of CO2 from the atmosphere (Tonn and Marland 2006).
Ontario’s managed forests were estimated to contain 6.19 billion tonnes of carbon in 2000 (Colombo et al.
2007a), the equivalent of 22.72 billion tonnes of CO2. These forests are projected to increase carbon storage by
69.4 million tonnes between 2000 and 2100, or about 0.7 million tonnes per year (Colombo et al. 2007a). When
carbon in wood products is included, storage increases to 433.8 million tonnes of carbon between 2000 and 2100
(Colombo et al. 2007a, Chen et al. 2008). This increase equates to an average removal of 15.9 million tonnes of
CO2 from the atmosphere annually.
Energy used to create wood products results in some carbon emissions, but projections for Ontario show that
these emissions are much less than the overall net reduction in atmospheric greenhouse gases from sustainable
forest management and the use of wood (Colombo et al. 2007a). Emissions from transporting wood to mills and
burning fossil fuels during manufacturing were estimated to be roughly 9% of the amount of carbon stored in wood
products from Ontario (Colombo et al. 2007a).
In addition, using wood products produces important indirect reductions in greenhouse gas emissions. For
example, wood from sustainably managed forests used as a biofuel is carbon neutral, and the energy generated
reduces the need to burn fossil fuels (Gustavsson et al. 1995). When wood is used to replace building materials
such as steel, aluminium, bricks, and concrete, which require more energy and thus emissions to produce,
greenhouse gas emissions are reduced (Eriksson et al. 2007, Sathre 2007). In a review of building materials used
in Scandinavia, wood construction consistently resulted in lower greenhouse gas emissions than did other materials
(Petersen and Solberg 2005).
Increasing carbon storage in Crown forests could be accomplished by adjusting policies and allocating funding
to promote silvicultural practices that increase carbon sequestration, such as tree planting (Richards et al. 1997).
Government policy affects most Ontario and Canadian forests, since most managed forest is publicly owned.
Governments can provide incentives to encourage carbon storage on private land, including subsidies for carbon
sequestered, and the creation of a market for stored carbon (Richards et al. 1997). In 2007, the Ontario government
used one such tool, when assistance for afforestation was announced to plant 50 million trees by 2020 on private
land in the southern part of the province (UNEP 2007).
Several researchers have considered how taxes or subsidies for carbon stored in forests could affect forest
economics (e.g., Binckley and van Kooten 1994). However, disregarding carbon storage in wood products and
the reduced emissions from using wood in place of fossil fuel or energy-intensive building materials provides an
incomplete and misleading picture of overall effects of such incentives. As Binkley and van Kooten (1994) pointed
out, forests and people beneit when governments use carbon taxes to promote carbon storage in forests, as well
as materials policies that lengthen the lifespan of wood products and promote use of wood products over those
manufactured from more energy-intensive materials (Binckley and van Kooten 1997, Lippke et al. 2004, Gustavsson
et al. 2006).
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CLIMATE CHANGE RESEARCH REPORT CCRR-12
Managing forests for the highest overall carbon storage, including wood products, is an important issue
confronting foresters. Public concern about how forestry practices affect national and global carbon stocks is
increasing, as predicted by Pollard (1989). Sustainable management of forests for multiple social and ecological
beneits, of which timber production is one, is now common practice in Ontario and the rest of Canada. The IPCC
(2007b) states that sustainable management that maintains forest carbon stocks and produces sustained yield of
wood products is the most effective strategy to use forests to mitigate climate change. Forest managers and the
public overall need to understand that future sustainable forest management may have to include harvesting timber
and creating wood products as part of a suite of activities designed to promote tree species adaptation to new
conditions, increase forest carbon storage, reduce emissions, and slow climate change.
Conclusions
Early in this paper, I described a scenario in which forests are exposed to an environment that has not existed
for at least 100,000 years. Only a few decades ago, many people would have viewed this scenario as science
iction, but now evidence is growing that this rapid climate change is underway. Under some projections, in the time
it takes for a typical forest rotation, climate change would cause average temperatures in Ontario to rise up to 5oC
warmer in summer and 9oC warmer in winter, with CO2 levels tripling. Forest managers potentially will face many
challenges under such rapid change, including increased forest ires, severe unexpected insect infestations and
disease outbreaks, and forest decline due to drought. They may also see some beneits, such as increased tree
growth where moisture and nutrients are not limiting.
Evidence suggests that we are now seeing climate change effects, and experts are predicting that climate
change will result in large-scale ecosystem change. However, so far forest management is still based on a
constant-climate paradigm (Parker and Colombo 2003). As McLachlan et al. (2007) state: “We… strongly reject
the…ubiquitous ‘business as usual’ scenario that is the current de facto policy.” Given the inevitability of climate
change and the potential effects of it and elevated atmospheric CO2, it is imperative to consider how such changes
will affect forests and forestry and how forest management can adapt. Adaptation and mitigation options discussed
in this paper are shown in Table 1.
Debates about how and when to adapt to climate change will continue, but most governments are no longer
reticent about the need to incorporate climate change into forest management decision-making. Now that
climatologists are making more conident assertions about the likelihood of climate change and governments are
starting to act to control greenhouse gas emissions, the following question is taking on increased urgency: When
will it be appropriate for foresters to discard the constant-climate paradigm and intervene to adapt forests to the
changes that are underway?
Clearly, they must begin acting soon, since many of their decisions affect forests for 50 or more years, during
which time the climate will change. For action to take place, foresters, biologists, and other resource managers
need clear direction to involve them in developing management techniques that identify and reduce harmful
impacts of climate change. These activities need to be coordinated and carefully thought out, and they will
require policies that link well-planned research with ield-testing of adaptive measures. To develop such policies,
governments need a better understanding of the response of forests to environment as well as models that use
such information to project future forest condition. This work will help deine levels of uncertainty and guide forest
managers as to when and how to intervene to reduce risks of climate change impacts.
CLIMATE CHANGE RESEARCH REPORT CCRR-12
Table 1. Some potential climate change strategies for forest adaptation and climate change mitigation.
Have multi-disciplinary panels of local experts and scientists develop adaptation options, prioritized by risk (high,
moderate, low) and scale of implementation area (large, medium, small)
Alter harvest rates
1. Adjust ire and forest management strategies to maintain desired stand age distribution and total area disturbed if
rates of natural disturbance change
2. Consider harvesting forests at high risk of loss to disturbance or general decline before they reach their otherwise
optimal rotation age, to allow better-adapted species or populations to move in and permit utilization/capture of
woody carbon in forest products
3. Consider salvage harvesting in disturbed areas to meet wood supply needs
Construct more all-weather logging roads to address shortening of the period of winter harvesting due to later freezeup and earlier thawing
Develop forest projections that incorporate the effects of climate change (and elevated CO2) on growth rates
Apply silviculture to optimize return on investment
1. Concentrate silvicultural efforts on forested sites likely to remain productive despite climate change
2. Plant drought-tolerant species on drier sites
3. Plant fast-growing, genetically improved trees in areas not expected to experience frequent drought
4. Use silvicultural practices that increase water availability, such as competition control during regeneration
Plant seed from local sources with some that are expected to be better adapted to the changing climate
Maintain high levels of genetic diversity
Increase planting rates to assist slow natural redistribution of genotypes and species
Harvest forests according to the principles of sustainable forest management, using wood products as biofuel and
building materials
Forest management decisions based on future rather than past climate information should increase forest
sector carbon while reducing potential impacts of climate change. Implementing such strategies in the short term
will not only help mitigate climate change but also expand markets for a forest industry presently facing serious
economic challenges. New products could include those that replace more energy-intensive materials such as
concrete and steel as well as wood-based biofuels (Ter-Mikaelian et al. 2008). Forestry should play a role in
reducing climate change through increasing carbon storage and helping decrease emissions in other sectors.
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CLIMATE CHANGE RESEARCH REPORT CCRR-12
Climate Change Research Publication Series
Climate Change Research Reports
CCRR-01 Wotton, M., K. Logan and R. McAlpine. 2005. Climate Change and the Future Fire Environment in Ontario: Fire Occurrence and Fire
Management Impacts in Ontario Under a Changing Climate. Ontario Ministry of Natural Resources, Applied Research and Development Branch,
Sault Ste. Marie, Ontario. Climate Change Research Report CCRR-0. 23 p.
CCRR-02 Boivin, J., J.-N. Candau, J. Chen, S. Colombo and M. Ter-Mikaelian. 2005. The Ontario Ministry of Natural Resources Large-Scale Forest
Carbon Project: A Summary. Ontario Ministry of Natural Resources, Applied Research and Development Branch, Sault Ste. Marie, Ontario.
Climate Change Research Report CCRR-02. 11 p.
CCRR-03 Colombo, S.J., W.C. Parker, N. Luckai, Q. Dang and T. Cai. 2005. The Effects of Forest Management on Carbon Storage in Ontario’s Forests. Ontario Ministry of Natural Resources, Applied Research and Development Branch, Sault Ste. Marie, Ontario. Climate Change Research
Report CCRR-03. 113 p.
CCRR-04 Hunt, L.M. and J. Moore. 2006. The Potential Impacts of Climate Change on Recreational Fishing in Northern Ontario. Ontario Ministry of
Natural Resources, Applied Research and Development Branch, Sault Ste. Marie, Ontario. Climate Change Research Report CCRR-04. 32 p.
CCRR-05 Colombo, S.J., D.W. McKenney, K.M. Lawrence and P.A. Gray. 2007. Climate Change Projections for Ontario: Practical Information for
Policymakers and Planners. Ontario Ministry of Natural Resources, Applied Research and Development Branch, Sault Ste. Marie, Ontario.
Climate Change Research Report CCRR-05. 37 p.
CCRR-06 Lemieux, C.J., D.J. Scott, P.A. Gray and R.G. Davis. 2007. Climate Change and Ontario’s Provincial Parks: Towards an Adaptation Strategy. Ontario Ministry of Natural Resources, Applied Research and Development Branch, Sault Ste. Marie, Ontario. Climate Change Research
Report CCRR-06. 82 p.
CCRR-07 Carter, T., W. Gunter, M. Lazorek and R. Craig. 2007. Geological Sequestration of Carbon Dioxide: A Technology Review and Analysis of Opportunities in Ontario. Ontario Ministry of Natural Resources, Applied Research and Development Branch, Sault Ste. Marie, Ontario. Climate Change
Research Report CCRR-07. 24 p.
CCRR-08 Browne, S.A. and L.M Hunt. 2007. Climate change and nature-based tourism, outdoor recreation, and forestry in Ontario: Potential effects and adaptation strategies. Ontario Ministry of Natural Resources, Applied Research and Development Branch, Sault Ste. Marie, Ontario. Climate Change
Research Report CCRR-08. 50 p.
CCRR-09 Varrin, R. J. Bowman and P.A. Gray. 2007. The known and potential effects of climate change on biodiversity in Ontario’s terrestrial ecosystems: Case
studies and recommendations for adaptation. Ontario Ministry of Natural Resources, Applied Research and Development Branch, Sault Ste. Marie,
Ontario. Climate Change Research Report CCRR-09. 34 p + append.
CCRR-10 Dixon, R.L. and J. Gleeson. 2008. Climate change and renewable energy in Ontario: Mitigation and adaptation. Ontario Ministry of Natural Resources, Applied Research and Development Branch, Sault Ste. Marie, Ontario. Climate Change Research Report CCRR-10. (in press)
CCRR-11 Dove, D., I. Cameron and L. Demal. 2008. Climate change and Ontario’s water resources: A discussion of potential impacts and water resource management considerations. Ontario Ministry of Natural Resources, Applied Research and Development Branch, Sault Ste. Marie, Ontario. Climate
Change Research Report CCRR-11. (in press)
Climate Change Information Notes
CCRN-01 Warner, B.G., J.C. Davies, A. Jano, R. Aravena, and E. Dowsett. 2003. Carbon Storage in Ontario’s Wetlands. Ontario Ministry of Natural
Resources, Sault Ste Marie, Ontario, Canada. Climate Change Research Information Note Number 1. 4 p.
CCRN-02 Colombo, S.J. 2006. How OMNR Staff Perceive Risks Related to Climate Change and Forests. Ontario Ministry of Natural Resources,
Sault Ste Marie, Ontario, Canada. Climate Change Research Information Note Number 2. 8 p.
CCRN-03 Obbard, M.E., M.R.L. Cattet, T. Moody, L.R. Walton, D. Potter, J. Inglis, and C. Chenier. 2006. Temporal Trends in the Body Condition of
Southern Hudson Bay Polar Bears. Ontario Ministry of Natural Resources, Sault Ste Marie, Ontario, Canada. Climate Change Research Information Note Number 3. 8 p.
CCRN-04 Jackson, B. 2007. Potential Effects of Climate Change on Lake Trout in Atikokan Area. Ontario Ministry of Natural Resources, Sault Ste.
Marie, Ontario, Canada. Climate Change Research Information Note Number 4. 4 p.
CCRN-05 Bird, N.D. and E. Boysen. 2006. The Carbon Sequestration Potential from Afforestation in Ontario. Ontario Ministry of Natural Resources,
Sault Ste Marie, Ontario, Canada. Climate Change Research Information Note Number 5. 4 p.
CCRN-06 Colombo, S.J., J. Chen, M.T. Ter-Mikaelian. 2006. Carbon Storage in Ontario’s Forests, 2000-2100. Ontario Ministry of Natural Resources, Sault Ste Marie, Ontario, Canada. Climate Change Research Information Note Number 6. 8 p.
CCRN-07 Trumpickas, J., B.J. Shuter and C.K. Minns. 2008. Potential changes in future surface water temperatures in the Ontario Great Lakes as
a result of climate change. Ontario Ministry of Natural Resources, Sault Ste Marie, Ontario, Canada. Climate Change Research Information Note
Number 7. 8 p.
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