As reported in Deutsche Welle, the scientists used a novel technology (see below the fold for an image), called SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Cartography), to detect levels of atmospheric carbon dioxide. The unique device was built by the German Aerospace Center and has been in orbit on a satellite around the Earth since 2002.
SCIAMACHY is able to detect carbon dioxide by measuring the amount of sunlight reflected from the atmosphere; different gases reflect light differently so the scientists were able to accurately pinpoint carbon dioxide's signal. The scientists collected three years' worth of data before analyzing the results. Michael Buchwitz, one of the study's lead scientists, said he was confident of the group's findings, explaining that "the raised CO2 concentrations can be attributed to human activities because the patterns in this European urban area are very stable," despite slight fluctuations caused by seasonal changes.
If Germany truly intends on significantly reducing its greenhouse gas emissions, they could do worse than follow these policy prescriptions: stop all proposed coal power plant projects and impose stricter regulations on the existing ones.
Image courtesy of hAdamsky via flickr