Virtual Posters

This study analyses synoptic observations from the base Faraday/Vernadsky between 1960 and 2005 to investigate whether and how these changes have had an effect on clouds and precipitation. Results show that the total cloud cover (TCC) has increased significantly, with the biggest increase observed in winter (more than 0.6 okta over the whole period) and positive tendencies in all seasons. Consequentially this also shows in a significant increase in the number of precipitation events in winter (13 events per decade) during the period under investigation. Observational records indicate that the increase in total cloud cover is caused by an increase in the amount of medium and/or high clouds which agrees with the finding that the medium height cloud type “Altostratus opacus or Nimbostratus” is the one most often recorded during precipitation events. The atmospheric warming has also affected the type of precipitation. In spring and autumn, when the air temperature is around freezing point, the proportion of non-frozen precipitation has increased significantly. The higher proportion of non-frozen precipitation is likely to reduce the albedo in the region and will thus contribute to the temperature-albedo feedback. During spring and autumn much of this liquid precipitation will fall on frozen ground where it cannot be stored but will run off and hence be unavailable for the biota.