Physical and Geographic Conditions
The weather and climate in the area of Akademik Vernadsky station are determined by its location on the islands of the Argentine archipelago, 8-10 kilometers away from the west coast of the Antarctic Peninsula. To a large extent, the wind regime and the nature of the weather around the station forms the mountain range of the peninsula: the fact that its coastline is dismembered, and some peaks reach 2800 m, causes birth of local phenomena such as foehns, stock winds reaching the station, and typical orographic clouds. The of the Argentine Islands archipelago itself, due to its small area and mostly sloping relief, has no significant effect on weather conditions.
The climate on the station is relatively mild (marine sub-Antarctic). Since the Pacific Ocean, the southern waters of which surround the islands of the archipelago, acts as a giant heat accumulator, in winter the air temperature rarely drops below -20 ° C. In summer, on the contrary, the cooled water and the snow cover do not allow the air to warm up much higher than zero.
The average air temperature is about -4 degrees but as can be clearly seen from the diagram of changes in the average annual temperature, in recent decades, it has noticeably increased. The severe weather conditions of past times are confirmed by the table of meteorological records on the station.
The annual amount of precipitation over the past 25 years has varied from 220 to 670 mm.
Features of weather and atmospheric circulation
In the area of the Antarctic Peninsula, cyclonic weather prevails. Atmospheric vortex systems develop over the Pacific Ocean and the Bellingshausen Sea and, moving eastward encounter the ridge of the peninsula. Such processes cause frequent precipitation and strong winds around the station. Thus, during transitional seasons, winds over 30-35 m / s are observed. According to statistics, about three hundred (!) days per year the snow falls, and only 25-30 (!) days the sky is almost cloudless. Sharp deterioration of the weather and snowstorms are observed during the passage of the atmospheric fronts of cyclones, however, often it is difficult to predict manifestations of non-frontal short-term snowfalls and blizzards. Therefore, during the winter period, an average of 1 to 2 meters of snow accumulates, gradually melting during the summer.
The anticyclone type of weather occurs less frequently and is associated with the influence of high-pressure ridges that spread from the continent or from the north. In this case, the southern wind from the continental Antarctica brings cooled air masses and for a considerable time a calm frosty weather is established, sometimes with fogs and hoarfrost. In summer, as a result of a long polar day and open water, cold air quickly warms up, and there are almost no temperature drops. Direct sunlight, supplemented by scattered light from snow and clouds, compensates for the lack of heat in the air, thereby creating absolutely comfortable conditions for staying outdoors.
Occasionally, cold air intrusions into the unfrozen water area occur, and mirages in the form of “flying icebergs” on the horizon become commonplace.
Weather information at the station is regularly transmitted to meteorologists to global databases, where it is used to calculate operational weather forecasts.