A group called “Environment Iowa” has released a report showing overnight temperatures in Iowa are “getting hotter.” Andrew Hug of Environment Iowa says last year in Des Moines, the average minimum overnight temperature was nearly two degrees above normal. “Warmer nighttime temperatures exacerbate public health problems because people need cooler nighttime temperatures to recover from heat exposure during the day,” Hug says.

According to Hug, higher overnight temperatures cause problems for farmers, too. “Certain species of insects and diseases, it’s the nighttime temperatures that keep those bugs and diseases down to the south,” Hug says. “That’s just one example and all the indications are it’s just going to get worse.”

Environment Iowa analyzed records from the National Climactic Data Center at four weather-reporting stations in Iowa. In Davenport, the average overnight temperature was 2.2 degrees above normal in 2007. The data showed the average overnight temperature in Waterloo was 1.6 degrees above normal last year. Dubuque’s data indicated overnight temperatures were one degree above normal in 2007.

Hug contends that’s all an indication of global warming. “Temperatures are going up is the general thrust of it,” Hug says. Hug points to global statistics which indicate seven of the eight warmest years on record have occurred since 2001 and Hug says it’s time for politicians to take steps to “avert the worst effects of global warming.”