If you’re getting sick of the cold weather, you can blame the hot summer that just passed. New research suggests that particularly hot summers cause really cold winters.
According to researchers from the Atmospheric and Environmental Research (AER), the University of Massachusetts, and the University of Alaska Fairbanks, the harsh winters that are currently evoked in the Northern Hemisphere could be caused by increasing temperatures and melting ice in the Arctic regions creates more snowfall and cold weather in the the later fall months at lower latitudes.
The team found that the strongest cooling trends in the winter were located with in the United States, southern Canada, and most of northern Eurasia. They believe that this is not entirely due in part by the natural variability of the climate system.
Previously, research has not come up with many solutions to extremely harsh, random weather conditions, such as unforeseen snowfall in more tropical areas. Instead, this new research suggests that because there has been a trend of increasingly cold winters over the last twenty years, it could be connected to the warmer temperature in the fall, skewing with what is a normal weather pattern. This causes temperatures to plummet in the winter season.
Through their studies, the team found that when there was a strong warming weather through summery July, August, and September, and then this continued through October and November, it seems to enhance the melting of sea ice in the Arctic.
In turn, this warmer weather, along with the melting of the sea ice, allowed the atmosphere in the Arctic to hold much more moisture. As a result, there is an increase in the possibility of precipitation over southern areas, such as Eurasia. This, then, falls as snow because of the temperatures are below freezing. This is also backed by the fact that over the last two decades, the snowfall has increased in the areas that were studied.
The group of researchers believe that because there is an increase in the snow cover, it affects the Arctic Oscillation. The Arctic Oscillation is an atmospheric pressure pattern that is found in the mid-latitudes to high latitudes, which causes it is remain in the “negative phase”.
This “negative phase” means that there is higher pressure over the Arctic region, which has pushes cold air into the mid-latitude regions. Among these mid-latitude regions are the United States and northern Canada, which is why the colder winters are observed.
The researchers don’t doubt the facts we already know: the world is getting warmer. And yes, just because of the cold winters, it doesn’t mean that the warmer temperatures aren’t favored. However, they also believe that because there is more snow, this is somehow related. As it continues to get warmer in the fall, the snow will soon turn into rain, which may reduce and eventually eliminate winter cooling altogether.
One of the clearest reasons that there has been no research and activity on this done in the past is that most climate models do not pick up the rends in winter cooling, accounting for the snow cover. This study, then, focusing on the importance of snow cover, has brought this issue forward, which will now improve future accuracy of seasonal forecasts.
The research shows that by using the snow cover as a main focus in the seasonal forecast, it can provide a more accurate forecast overall. The current models fail to do this, and miss one of the most (or, perhaps, the most) important factors that relates to the influence of winter.
The study was published January 13, in the Institute of Physics Publishing’s journal Environmental Research Letters.