By: Brielle Mears
Summary: La Niña is a climate event where the Pacific Ocean surface cools more than normal and the air pressure decreases over the western Pacific. It occurs typically every 3 to 5 years. For places like Asia, India, Africa, and Brazil, this means an increased amount of rainfall in the summers. For places in the Northern tier of the United States, like Michigan, this means more cold and dry winters. Because La Niña is a naturally occurring event, there is nothing in our power that we can do to prevent it. The only thing we can do is prepare for it. The most important thing we can do, besides the obvious such as buying warmer clothes and paying our heating bill, is prepping our homes. Make sure to have your water running relatively consistently to avoid the pipes from freezing. Make sure your windows and doors are properly sealed and air tight so the cool air cannot seep inside. Make sure to safely remove heavy buildups of snow from your roofs and gutters to prevent them from caving in. By now, if you are a native to Michigan, these should be standard procedures that you’ve most likely been doing already to winterize your home. La Niña is not something that is new to us. If anything, most welcome it! Winters like this means more snow and more consistently cold temperatures. It is every winter lovers dream! La Niña produces ideal conditions for snowboarding, snowmobiling, ice fishing, etc. For ice fishers, La Niña helps bring up bigger game to catch. The upwellings in the Pacific Ocean carry the nutrient-rich waters to the surface. These waters then draw the smaller fish and crustaceans to the surface to feed, which in turn, brings up the larger predators to prey on them. In the southern tier of the United States, in places such as California and Florida, La Niña produces warmer and drier conditions. Environments like this increase the risk of wildfires and droughts. For example, La Niña is thought to be a cause of the Dust Bowl drought in the 1930s and the 1988 drought that hit the American Midwest. This cost the United States nearly $40 billion in damages. La Niña can also be tied in as one of the factors that contributed to the intensive wildfires we have experienced along the west coast this year.
Why we should care? The temperature fluctuations that La Niña produces could directly affect our crops. The colder temperatures could cause premature frosting which could kill the crops, therefore directly affecting our farmers source of income.
I have chosen this article as I think it does a good job further explaining how La Niña works. They incorporate useful charts and graphs into their work as well for those who are more visual learners. These charts depict the sea surface temperatures of the Pacific Ocean in order for us to predict just how cold of a winter we have in store for us. This article is also consistently being updated and it provides a link that you can check at anytime for updates on how La Niña is/will affect our winter here in Michigan.
Science in Action.
Dr. Jacob Bjerknes was been a meteorologist at the University of Leipzig.
Dr. Jacob Bjerknes is actually the man accredited with the discovery of La Niña. In the 1960s, while he was studying Canton Island in the Southern Pacific Ocean, he found that there was a change in the ocean pressure pattern and temperature during different cycles of time. This cycle became known as Bjerknes feedback. During La Niña, the eastern Pacific Ocean cools, and the air begins to sink and dry out. This is what causes the cold and dry winters in the Northern part of the United States, and the drought-like conditions in the southern part of the U.S.. In the western Pacific Ocean, the temperature of the ocean warms, causing the air to rise, moisten, and thicken. This is what causes the heavy thunderstorms and floods in places like Asia. This rising and sinking motion of the air then produces strong winds that blow from the east to the west. These winds push the water from the eastern Pacific to the Western, which causes upwelling of the colder water. This cools the surface even more (producing those stronger winters). These same winds help push the warm surface water that’s in the western part of the Pacific over to places like Indonesia, producing the tropical conditions.