We investigate the wind driven velocity structure of the California Current (CC) using a 12-year ... more We investigate the wind driven velocity structure of the California Current (CC) using a 12-year time series of ageostrophic velocities, ocean surface winds, and two regression models of the system. The ageostrophic current is estimated by removing geostrophic velocities, which are determined by the combination of CTD (conductivity, temperature, depth) and altimetry data from total flow velocity observations. Total current
Correction to “A comparison of solar tides derived from UARS high-resolution Doppler imager wind ... more Correction to “A comparison of solar tides derived from UARS high-resolution Doppler imager wind measurements with simulations from the NCAR thermosphere-ionosphere-mesosphere electrodynamics general circulation model” by Dong L. Wu, Paul B. Hays, and Raymond G. Roble
The generation of climate data records (CDRs) is a critical step in providing the necessary infor... more The generation of climate data records (CDRs) is a critical step in providing the necessary information for scientists, decision-makers, and stakeholders to make adaptive choices that could improve the nation's resiliency to environmental change and variability, maintain our economic vitality, and improve the safety and comfort of U.S. citizens. These CDRs are particularly needed for the Arctic, where existing evidence
... Aagaard, K., and EC Carmack, The Role of Sea Ice and Other Fresh Water in the Arctic Circulat... more ... Aagaard, K., and EC Carmack, The Role of Sea Ice and Other Fresh Water in the Arctic Circulation, - *HRSK\V 5HV , 94, C10, 14485 ... Emery, WJ, CW Fowler and JA Maslanik, Satellite Derived Maps of Arctic and Antarctic Sea Ice Motion: 1988 1994, *HRSK\V 5HV /HWW , 24, 8 ...
IEEE International IEEE International IEEE International Geoscience and Remote Sensing Symposium, 2004. IGARSS '04. Proceedings. 2004
The Maximum Cross Correlation (MCC) method is used with infrared and passive microwave images of ... more The Maximum Cross Correlation (MCC) method is used with infrared and passive microwave images of sea surface temperature (SST) along with ocean color images to compute sea surface currents from sequential imagery. These surface currents are then merged with geostrophic surface currents computed from coincident satellite altimetry observations to yield a high spatial resolution map of the surface mesoscale currents
Surface coastal currents off California are a good example of the complex variability in space an... more Surface coastal currents off California are a good example of the complex variability in space and time of currents in an ocean basin eastern boundary. Conventional oceanographic measurements are unable to resolve these relatively small scale variations but by employing both satellite imagery and satellite altimetry we are able to resolve this complex structure and its variations in space and time. Moreover using historical satellite imagery we are able to extend this study back into the past. Our emphasis will be on resolving these variations and later studies will relate these variations to various forcing functions.
Proceedings of IGARSS '94 - 1994 IEEE International Geoscience and Remote Sensing Symposium, 1994
Heat transfer and ice production in the ice-covered seas is controlled to a large extent by ice m... more Heat transfer and ice production in the ice-covered seas is controlled to a large extent by ice motion, which is in turn a function of winds and atmospheric boundary layer conditions. While sea-ice models appear to capture the general elements of this interaction, relatively little data have been available to verify model performance or to assess the spatial and temporal variability of ice motion. Several satellite remote sensing instruments provide the capability of detecting ice displacements. In combination with drifting buoy data, it is now possible to create detailed motion fields suitable for studying mesoscale responses of the ice pack to wind forcing. AVHRR, SAR, and drifting buoys have been merged using optimal interpolation techniques to generate daily gridded ice velocity fields for the Beaufort Sea from June 1992 thru July 1993. These motion fields are compared to simulations using a dynamic-thermodynamic ice model with different ice rheologies and heat transfer processes. The motion fields are discussed in terms of responses to various atmospheric synoptic regimes, and sources of differences between observed and simulated motions are considered. The remotely-sensed ice motion fields show seasonal and temporal variability not apparent in the relatively widely-spaced buoy network. Ice velocities and divergence rates agree in general with the simulations. The cavitating fluid and viscous-plastic ice rheologies yield similar drift directions, but can differ substantially in drift speed under strong winds. The overall utility of AVHRR-based ice motion fields is discussed. Possibilities of assimilating the daily motion fields directly into the ice model to assist in refining the thermodynamic portion of the model is described
As one of the few places in the ocean where winter cooling/mixing creates conditions where water ... more As one of the few places in the ocean where winter cooling/mixing creates conditions where water from the surface can penetrate into the deep ocean the Labrador Sea is an area of interest to people studying climate change in the ocean. Persistent cloud cover over this area makes it impossible to use infrared satellite imagery to relate space/time changes in
We investigate the wind driven velocity structure of the California Current (CC) using a 12-year ... more We investigate the wind driven velocity structure of the California Current (CC) using a 12-year time series of ageostrophic velocities, ocean surface winds, and two regression models of the system. The ageostrophic current is estimated by removing geostrophic velocities, which are determined by the combination of CTD (conductivity, temperature, depth) and altimetry data from total flow velocity observations. Total current
Correction to “A comparison of solar tides derived from UARS high-resolution Doppler imager wind ... more Correction to “A comparison of solar tides derived from UARS high-resolution Doppler imager wind measurements with simulations from the NCAR thermosphere-ionosphere-mesosphere electrodynamics general circulation model” by Dong L. Wu, Paul B. Hays, and Raymond G. Roble
The generation of climate data records (CDRs) is a critical step in providing the necessary infor... more The generation of climate data records (CDRs) is a critical step in providing the necessary information for scientists, decision-makers, and stakeholders to make adaptive choices that could improve the nation's resiliency to environmental change and variability, maintain our economic vitality, and improve the safety and comfort of U.S. citizens. These CDRs are particularly needed for the Arctic, where existing evidence
... Aagaard, K., and EC Carmack, The Role of Sea Ice and Other Fresh Water in the Arctic Circulat... more ... Aagaard, K., and EC Carmack, The Role of Sea Ice and Other Fresh Water in the Arctic Circulation, - *HRSK\V 5HV , 94, C10, 14485 ... Emery, WJ, CW Fowler and JA Maslanik, Satellite Derived Maps of Arctic and Antarctic Sea Ice Motion: 1988 1994, *HRSK\V 5HV /HWW , 24, 8 ...
IEEE International IEEE International IEEE International Geoscience and Remote Sensing Symposium, 2004. IGARSS '04. Proceedings. 2004
The Maximum Cross Correlation (MCC) method is used with infrared and passive microwave images of ... more The Maximum Cross Correlation (MCC) method is used with infrared and passive microwave images of sea surface temperature (SST) along with ocean color images to compute sea surface currents from sequential imagery. These surface currents are then merged with geostrophic surface currents computed from coincident satellite altimetry observations to yield a high spatial resolution map of the surface mesoscale currents
Surface coastal currents off California are a good example of the complex variability in space an... more Surface coastal currents off California are a good example of the complex variability in space and time of currents in an ocean basin eastern boundary. Conventional oceanographic measurements are unable to resolve these relatively small scale variations but by employing both satellite imagery and satellite altimetry we are able to resolve this complex structure and its variations in space and time. Moreover using historical satellite imagery we are able to extend this study back into the past. Our emphasis will be on resolving these variations and later studies will relate these variations to various forcing functions.
Proceedings of IGARSS '94 - 1994 IEEE International Geoscience and Remote Sensing Symposium, 1994
Heat transfer and ice production in the ice-covered seas is controlled to a large extent by ice m... more Heat transfer and ice production in the ice-covered seas is controlled to a large extent by ice motion, which is in turn a function of winds and atmospheric boundary layer conditions. While sea-ice models appear to capture the general elements of this interaction, relatively little data have been available to verify model performance or to assess the spatial and temporal variability of ice motion. Several satellite remote sensing instruments provide the capability of detecting ice displacements. In combination with drifting buoy data, it is now possible to create detailed motion fields suitable for studying mesoscale responses of the ice pack to wind forcing. AVHRR, SAR, and drifting buoys have been merged using optimal interpolation techniques to generate daily gridded ice velocity fields for the Beaufort Sea from June 1992 thru July 1993. These motion fields are compared to simulations using a dynamic-thermodynamic ice model with different ice rheologies and heat transfer processes. The motion fields are discussed in terms of responses to various atmospheric synoptic regimes, and sources of differences between observed and simulated motions are considered. The remotely-sensed ice motion fields show seasonal and temporal variability not apparent in the relatively widely-spaced buoy network. Ice velocities and divergence rates agree in general with the simulations. The cavitating fluid and viscous-plastic ice rheologies yield similar drift directions, but can differ substantially in drift speed under strong winds. The overall utility of AVHRR-based ice motion fields is discussed. Possibilities of assimilating the daily motion fields directly into the ice model to assist in refining the thermodynamic portion of the model is described
As one of the few places in the ocean where winter cooling/mixing creates conditions where water ... more As one of the few places in the ocean where winter cooling/mixing creates conditions where water from the surface can penetrate into the deep ocean the Labrador Sea is an area of interest to people studying climate change in the ocean. Persistent cloud cover over this area makes it impossible to use infrared satellite imagery to relate space/time changes in
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