As most of you have probably noticed, this winter has been full of snow and cold weather. While the temperature did not reach -22 degrees in Western PA (which is the coldest temperature ever recorded in the Pittsburgh area on Jan. 19, 1994), we’ve had our fair share of frigid weather and snow.
Most of these blasts of cold air can be contributed to what scientists call a changing of jet stream patterns. A jet stream is a narrow stream of mostly western wind currents that circle the earth about seven miles above the ground. There are typically two or three jet streams in each the northern and southern hemispheres. A new study seems to show that the jet stream of North America may be taking a longer path as a result of the warming arctic.
Temperatures have been warming two to three times more in the arctic areas than the rest of the globe. This translates into more melting of arctic glaciers and increased sea levels in the ocean which leads to higher tides at the beach. This means that as the temperature difference decreases between the arctic and the middle latitudes, the jet stream slows down. This draws the conclusion that cold weather tends to last longer in the northern United States.
This also means that warmer weather will be found farther to the north and colder weather farther to the south. States like Alaska have had warmer winters while cities like Atlanta have had many unusual snowstorms and colder than normal temperatures. So while most people say this cold weather cannot be attributed to global warming, the warming of the arctic has actually caused these colder temperatures that have been seen in parts of the country.
These snowy and cold winters can be expected to continue for the next few years, according to scientists at the World Meteorological Association. However, the summers in our area are expected to continue to stay on average for the next couple of years.