(NEXSTAR) – The planet has been getting just a little bit hotter every year, but the effects aren’t being felt equally. In the United States, some regions are just 1 or 2 degrees warmer than they were 50 years ago. In other areas, average winter temperatures have jumped 5 degrees Fahrenheit.
New data analysis from Climate Central shows the Northeast and the Great Lakes are disproportionately impacted by rising winter temperatures. In states like Indiana, New York, Maine, Vermont, New Hampshire, Wisconsin and Minnesota, every single region of the state studied has seen winters get 5 degrees warmer on average.
The five biggest increases since 1970 were seen in Burlington, Vermont (7.2°F); Concord, New Hampshire (6°F); Milwaukee (6°F); Chattanooga, Tennessee (5.8°F); and Green Bay, Wisconsin (5.8°F), according to Climate Central analysis.
The map is made using average temperature data from the National Oceanic and Atmospheric Administration. It shows how the average temperature in winter (December, January, February) has changed since 1970.
Climate Central said 98% of the approximately 250 cities it studied saw an increase in average winter temperatures since 1970.
There are just a few cities that buck the trend and have seen colder winters since 1970: Marquette, Wis.; Idaho Falls, Idaho; Eureka, Calif.; Denver; and Biloxi, Miss. What makes these cities the exceptions? It could have to do with a hyperlocal microclimate, or something else entirely.
“The ‘why’ behind most temperature outliers is not known,” said Jen Brady with Climate Central. She said the five cities with a slight cooling trend “are distributed without a strong regional connection, which further suggests we are dealing with local conditions that may be linked to the particular weather station and not a larger pattern.”
The larger pattern is illustrated by the data in the map above: warmer winters across the board.
What are the consequences of warmer winters? For one, the researchers point out that pests like mosquitoes could start flourishing in areas previously too cold to survive in. Certain fruit trees, like cherries and apples, also need a certain number of “chill hours” in winter in order to yield fruit in the spring and summer. Warmer winters also could mean smaller snowpacks – especially in the West where drought is a recurring problem. It also means a shorter ski and winter sport season – ruining the fun and hurting tourism at the same time.