Faculty conversations: Jeff Andresen
Jeff Andresen could tell you exactly what the weather was like on any given day in Michigan during the past 100 years.
"Our earliest records go back to Fort Detroit back in about 1821," he said. "Those records are not complete, but they still offer us a little bit of a glimpse when Michigan was becoming more populated."
Andresen is an associate professor in the Department of Geography and the state climatologist for Michigan. Forty-eight states have a climatology program, and Michigan’s has existed for about 100 years.
"We have 100 years of fairly good data to make a judgment or quantify what's happened," Andresen said. "And in that period, overall Michigan has gotten warmer, and it's gotten wetter."
Between 1910 and the late 1970s, Michigan's average temperature dropped by one degree. Between 1980 and the present, the average temperature has warmed by two degrees - a change that Andresen said is climatologically significant.
"The interesting thing about that two-degree period of warming is that it is seasonally-concentrated," Andresen said. "There is some warming in all seasons, but the majority of that warming has been in the cool seasons — winter, and to a lesser extent spring."
There is 10 to 15 percent more annual precipitation now than there was about 50 years ago - an increase of about 4 to 6 inches, he said.
"If we look at projections, all of them suggest that Michigan and the Great Lakes region will become warmer than it has been for a long, long time. And we could be looking at several degrees of warming just in the next 50 to 100 years," Andresen said. "Precipitation-wise, which is also just as important — there are more directions."
Andresen studies the impact of weather and climate on agricultural systems, particularly the impact of climate change and variability on corn, soybeans, wheat and tart cherries in Michigan.
A warmer and wetter climate is good for most of the 80 different crops grow in Michigan - but not all projections indicate that Michigan will be wetter, he said.
"Some of the projections say Michigan will be wetter, some say a little bit drier," Andresen said. "But if you look at the consensus, most of them say the annual precipitation might increase, but that most of that increase would be during the off-season, the cool season."
This distinction is important because crops need water during the growing season. An increase in temperature during the growing season might increase evaporation when crops need water most. If crops don’t adapt to this change, it could be a negative for some crops, Andresen said.
Michigan has a network of about 67 automated weather stations across Michigan, each of which monitors the temperature, dew point, relative humidity, wind speed and direction, precipitation, etc. In 2007, the network combined with MSU’s Integrated Pest Management program to form Enviro-weather, a collaborative project that provides weather-based pest, natural resources and production management tools.
"We conducted a survey last year of apple and cherry growers, and for this subset alone, they were able to save almost $2 million by using the data we provide," Andresen said. "So we know that there is economic value, and we continue to add new products and tools."