The first five months of 2012 were the warmest on record for many Great Lakes cities.
“The Midwest and upper Midwest just experienced a spring that was literally off the charts,” said Deke Arndt, chief of the climate monitoring branch at the National Climatic Data Center. “We literally had to rescale some of our charts to accommodate the warmth we saw this spring.”
Thirty-eight cities in the Great Lakes region knocked out serious long-standing heat records, according to the National Oceanic and Atmospheric Administration, which administers the data center. Nationwide, 104 cities set records.
“Folks around the Great Lakes are around or within one of the most unusual temperature episodes that we’ve seen in the U.S. since we’ve been keeping track of things,” Arndt said.
The unusually high temperatures in March caused fruits and vegetables in the region to start growing earlier. Unfortunately, the frost that followed the early spring start caused serious economic problems for farmers. Michigan lost 80 percent of its sweet cherry crop and 90 percent of its tart cherries because of the weird weather.
Over the past 43 years, Michigan is the second fastest warming state in the country, according to a map from Climate Central, a nonprofit news and research organization that analyzes and reports on climate science. It used data from the National Oceanic and Atmospheric Administration to make the comparison.
“We compute trends based on annual average temperatures and then we rank the trends from fastest to slowest,” said Claudia Tebaldi, research scientist at Climate Central. “So the ten fastest warming states are determined by the size of the linear trend.”
Minnesota is the third fastest warming state during that period and Wisconsin is fourth. Arizona is the first.
Among the Great Lakes records for 2012:
- Green Bay, Wis. had its warmest year since 1886 with an average yearly temperature of 41.4 degrees — a 7.1 degree increase from the city’s 1981-2010 average temperature.
- Sault St. Marie, Mich. had its warmest year since 1888 at an average yearly temperature of 36.4 degrees — a 6 degree increase.
- Peoria, Ill. had its warmest year since 1901 with an average yearly temperature of 48.7 degrees — a 6.6 degree increase.
- Evansville, Ind. had its warmest year since 1896 with an average yearly temperature of 53.8 degrees — a 6.2 increase.
The data center also measured the unusualness of the temperature hikes for 2012, making it easier for people to understand how drastic the changes are. The unusualness is based on how much each city’s 2012 temperature deviates from its long-term average.
Muskegon, Mich. has the highest unusualness rating of the Great Lakes record breakers at 3.6 and has an average temperature of 44.7 degrees for 2012. After Muskegon, the second highest unusualness rating in the region is 3.3 for Rochester, Minn. The lowest unusualness rating is 2.5 for Youngstown, Ohio.
Nationally, 2012 was the second warmest spring on record at an average temperature of 57.1 degrees, exceeding the previous warmest spring in 1910 by 2 degrees.
“In the U.S., in the long-term patterns, we are seeing southern warmth punch into the north earlier,” Arndt said. “That is consistent with a global pattern.”
Still, just because we’ve had a particularly warm spring this year doesn’t mean previous heat records will continue to be broken each year, Arndt said. “This particular season that we just experienced, though it’s consistent in the warming world, the direct proximal drivers were weather patterns.”
He compared the relationship between climate and weather to the relationship between a parent and a child.
“If you’re a parent, you have this long-term influence on your child, but you don’t drive their decisions every day,” said Arndt. “If the kid makes a good or bad decision, it’s based on different factors.”
In the same way, long-term climate patterns influence day-to-day weather, but don’t have complete control over it.
Despite the variability weather patterns give to climate change, Arndt is confident that the driving force of the heating trend is human-induced climate change caused by the burning of fossil fuels.
“We broke a lot of records this spring and threatened a lot of records too. It’s likely that we will continue to threaten the warm end of the records way more often over time.” Arndt said.