The Norwegian coast is familiar with polar lows, but it is often overlooked in Canada. Short-lived, but difficult-to-predict polar lows can cause considerable damage from strong winds and heavy snow.
On February 28, the Norwegian Meteorological Research Institute warned residents along the Finnmark coast of the next arrival. Polar low pressure.. One week later Norwegians under threat from another polar low, This time near Trondheim.
Polar lows, which often occur in low-population areas, are fatal. Therefore, we need to improve our ability to predict these sudden and violent storms.
My atmospheric science research focuses on these meteorological phenomena. I am a Center for Regional Climate Research and Simulation (ESCER), simulating polar lows using Canada’s regional climate model.
Polar lows are particularly difficult to predict due to their small size and short lifespan, leaving many questions unanswered. However, after a thorough review of the published scientific literature, we can answer many of the questions people have about polar lows.
Small but intense
Polar lows are intense maritime storms that occur near the poles in the colder months. Polar lows, less than 1,000 kilometers in diameter and typically lasting less than 48 hours, are smaller and have a shorter lifespan than winter storms that often affect eastern Canada.
Polar lows are associated with severe and sometimes hurricane forces, winds, heavy snow and other harsh weather conditions. Weather changes associated with polar lows are rapid.
As a result, polar lows pose a threat to coastal communities, sea and air transport, oil and gas platforms. Some polar lows have caused loss of life. For example, in October 2001, a polar low in Torsvogue developed near a fishing village on Van Noya Island in northern Norway. A ship capsized by a strong wind killed the crew.
Closer than I expected
Polar lows occur between the northern and southern hemispheres, between the poles, and at latitudes 40 degrees north and 50 degrees south, respectively. They form near the edges of sea ice (where sea ice meets the open ocean) or near snow-covered continents when very cold air flows over relatively warm waters.
The heat and humidity of the sea provide energy to the cold to promote the development of polar lows. Polar lows disappear when they land or move on sea ice, and their energy sources disappear.
Polar lows in the Labrador Sea, Davis Strait, and Hudson Bay have been observed near Canada. Due to the low population density of these areas, the risk of polar lows affecting the community is small.
In other parts of the world, polar lows can be dangerous. Norway and Japan are suffering from the effects of these storms due to the significant population density in coastal areas where polar lows can occur. Weather associated with polar lows can lead to road and airport closures, and there is also the risk of avalanches. For example, in January 2019, a polar low, in particular, landed in Norway, roads were closed and the village was isolated.
It can be expected that the location and frequency of polar lows will change as climate change occurs. For example, in the North Atlantic, as the edge of sea ice recedes, polar lows can form further north and become less frequent. However, many questions remain unanswered regarding the impact of climate change on polar low frequency and spatial distribution.
Difficult to predict storm
Accurate prediction of polar lows is essential to avoid damage caused by polar lows. However, polar lows are difficult to predict due to their small size and short lifespan.
As with any weather forecast, an essential element of a correct polar low pressure forecast is a well-understood and well-functioning atmospheric model of the current state of the atmosphere. However, the lack of conventional observations at sea or near the poles (such as observations from ground observatories) means that the initial conditions are not yet sufficient.
Recent developments in high-resolution atmospheric models (a set of equations that describe the evolving state of the atmosphere) have made it possible to predict polar lows more accurately than before. Scientists continue to work on these models, improving the way they represent heat exchange and other important processes between the ocean and the atmosphere.
Despite the fact that high-resolution models can correctly predict some polar lows, there is still much work to be done to successfully predict all these meteorological systems. In the meantime, be careful. The polar low in the Northern Hemisphere is not over yet.
Can polar bears and narwhals cling to the ice as it shrinks?
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Quote: Arctic Storms: How scientists are improving their predictions of dangerous polar lows (March 25, 2021) https: //phys.org/news/2021-03-arctic-storms Obtained from -scientists-dangerous-polar.html on March 25, 2021.
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How scientists are improving their predictions of dangerous polar lows
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