POPs

ln Part I (Storch and Xu 1990) the principal oscillation pattern (POP) analysis of 200mb equatorial velocity potential leads to the definition of a bivariate (POP-) index of the tropical 30- to 60-day oscillation. Using the POP pred iction scheme this index is predictable for a few days in advance. In Part II, the prediction of the equatorial velocity potential field, made by the POP method and made by two GCMs, is investigated. The POP index forecast can incorporate skillful forecasts of the equatorial velocity potential (X) field. Its ensemble correlation skill score passes the 0.50 level at 7 days, whereas persistence passes after 3 days. lf there is a strong 30- to 60-day oscillation signal in the initial state, useful forecasts of more tlnan 20 days are sometimes possible: if the initial signal is weak, the POP forecast fail s. Also. the forecast skill of two GCMs is considered. The NCAR T31 GCM appears to be quite sklllful in predicting the equatorial x-field, and in particular the 30- to 60-day oscillation. Its skill, however, is less than that of the POP scheme. The CNRM T4 GCM seems not to be able to predict the regular development associated with the tropical 30- to 60-day oscillation. The power of the POP index in explaining the equatorial x-field is a measure or the strength and dominance of the 30- to 60-day oscillation. This measure a t day 0 is an a priori indicator of the NCAR T31 GCM's skill in predicting the equatorial velocity potential field.

Fish living in the extreme conditions of the Tatra Mountain lakes were evaluated from a biological point of view as well as an important biomarker of long-range transported pollutants. In Veľke Hincovo pleso and in Morskie Oko, specimens of brown trout (Salmo trutta) of extraordinarily advanced age were found (ages of 18+ and 17+ years, respectively). The capture of a 17+ year-old brown trout in Morskie Oko (2400 g, 540 mm) indicated the presence of the so-called ferox life strategy. The growth of brook trout (Salvelinus fontinalis) was faster than the growth of brown trout in the younger year classes, and while the growth of brook trout stopped after the age of 5+, the growth of brown trout continued. Concentrations of long-range transported pollutants (HCHs, HCB, DDTs, PCBs, PBDEs, and trace metals) in the Tatra Mountain fish were mostly associated with fish age, body weight and length, type of fish tissue, and lake altitude. Persistent organic pollutants (POPs) in fish muscle wer...