United States National Research Council entitled "America's Climate Choices." Public advocacy Chameides has been active in highlighting the dangers of global warming, and has testified before the U.S. House of Representatives' Committee on Science, Space and Technology on the matter. In his testimony, delivered on April 25, 2013, he said that global warming is occurring, is primarily caused by human activity, and that it will have many negative effects on the United States, including, but not limited to, "more intense and frequent heat waves, risks to coastal communities from sea level rise, greater drying of the arid Southwest, and increased public health risks." He currently runs a blog on the Nicholas School of the Environment website called "The Green Grok," and has also blogged about global warming and other environmental issues on the Huffington Post and for Popular Science. Chameides has also written about the economics of climate change mitigation for both Science and for The Guardian. Additionally, after Joe Bastardi claimed on Fox News Channel that carbon dioxide can't cause global warming because of the first law of thermodynamics and Le Chatelier's principle, Media Matters for America contacted Chameides by email, who referred to Bastardi's claims as "utter nonsense." He has also, along with Alan Leshner, criticized the North Carolina government's proposal of a law in response to a report stating that sea levels were projected to rise about 39 inches over the next century. In an article for the News & Observer, they accused the law's supporters of trying to "disregard projections of sea level rise" and trying to "outlaw climate change." The law, which would prevent the government from using sea-level data based on anything except "historical data" for the next four years, was passed despite Chameides' objections. He has also criticized the cash for clunkers program by pointing out that, while one of its goals is to decrease CO2 emissions by promoting the purchase of more fuel-efficient cars, manufacturing new cars results in the production of carbon dioxide—he puts the figure at between 3 and 12 tons per car. He has also calculated that trading in a clunker that gets 18 mpg for a new car that gets 22 mpg would necessitate 5 and a half years of typical driving to offset the car's carbon footprint. Chameides has also written about other environmental issues, like chemicals used in certain consumer products. For example, when interviewed by