Some measurements of the development of the surface inversion in Central Alaska during winter     

Gerd Wendler  K. O. L. F. Jayaweera 《Pure and Applied Geophysics》1972,99(1):209-221

Summary The strong cooling rates of the surface air, which are observed in Fairbanks in winter immediately following clearing of the sky, can, in the first hours, be explained solely by the negative radiation balance. Later on, gravity drainage of cold air from the surrounding hills into the lower valley contributes about 30% to the observed energy loss of the air above the valley. Energy balance calculations show that the negative radiation balance is compensated mainly by sensible (62%) and soil heat flux (32%) while condensation contributes only a small 6%.

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Zusammenfassung Die starken Abkühlungsraten der bodennahen Luftschicht, die im Winter in Fairbanks beobachter werden, wenn die Bewölkung abnimmt, können in den ersten Studen allein durch die negative Strahlungsbilanz erklärt werden. Später hat der katabatische Wind, der kalte Luft von den Fairbanks umgebenden Hügeln in das niedriger liegende Tal bringt, einen Anteil an dem Energieverlust der Luft über dem Tal von etwa einem Drittel. Die Berechnung der Wärmebilanz zeigt, dass die negative Strahlungsbilanz hauptsächlich vom sensiblen Wärmestrom (62%) und dem Wärmestrom aus dem Boden (32%) kompensiert wird, während die Kondensation nur 6% beiträgt.

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Use of enhanced infrared satellite imagery for sea ice and oceanographic studies     

K.O.L.F. Jayaweera 《Ocean Engineering》1976,3(5):293-294

Infrared (i.r.) imagery from the NOAA 2,3, and 4 satellites could be used to measure accurately the absolute temperature of the sea surface and sea water. Comparison with measured temperatures indicate that the satellite observed values are within 2°C of those measured. Contouring temperatures and observing temperature fluctuations within 0·5°C is also possible by enhancing the infrared image. This is done by confining the 16 steps of gray of the image to a desired small temperature scale. The existence of open water areas within the pack ice and the positions of the ice edges could be readily distinguishable by generating special imagery in such a way that the gray scale covers two temperature ranges with a gray tone jump at the freezing point of sea water. In this way ice-water boundary appears as a line of demarcation between two different gray tones. Because the i.r. imagery is available all year round these techniques are readily applicable at all times especially during the winter months when the low sun angles make visible imagery not useful.  相似文献