Macomb, lIL – An expert on atmospheric science says humans are exacerbating the effects of global warming. Dr. Don Wuebbles of the University of Illinois says people often play down the human impact on the environment. He says a common misrepresentation is that the carbon dioxide produced by the environment nullifies the amount produced by humans in the form of transportation, industry and domestic emissions. Wuebbles says years of evidence suggest the earth is getting warmer, carbon dioxide concentrations are increasing and the planet's climate is changing. He says unless humans can check carbon dioxide emissions with alternative technologies, the midwest can expect a rise in summer temperatures of between five and 20 degrees over the next 100 years. Wuebbles made his comments during a presentation at WIU.