NASA links human activity with climate change

User Rating: / 4
PoorBest 

by William Atkins

Thursday, 22 May 2008

Page 1 of 2 ! On May 14, 2008, NASA announced that a Goddard Institute for Space Science study conducted by a team of international researchers concluded climate change caused primarily by human activities has impacted many of the natural systems on Earth. Related stories Worms in space: NASA confirms International Space Station infected Cows and deer head north, literally GLAST renamed Fermi Gamma-ray Space Telescope NASA announces Atlantis roll out to launch pad for Hubble mission NASA reports rocket explosion on Wallops Island The study, under the title “Attributing physical and biological impacts to anthropogenic climate change,” was published on May 15, 2008, in the journal Nature (453, 353-357, doi:10.1038/nature06937). The abstract to their paper begins, “Significant changes in physical and biological systems are occurring on all continents and in most oceans, with a concentration of available data in Europe and North America. Most of these changes are in the direction expected with warming temperature.” They added, “Here we show that these changes in natural systems since at least 1970 are occurring in regions of observed temperature increases, and that these temperature increases at continental scales cannot be explained by natural climate variations alone.” To prove their contention, the researchers developed and then analyzed a database of over 29,000 data series involving observed impacts on the natural systems of Earth. These impacts included data from about eighty studies, where each study contained at least twenty years of records (somewhere between 1970 and 2004). The specific impacts included such events as permafrost melting, lakes and rivers warming in temperature, glaciers shrinking in size, leaves unfolding and flowers blooming earlier in the spring, and birds arriving at earlier times during migration periods. They found that, on a global scale, about 90% of the observed changes to physical and biological systems were in the direction of warming temperatures. Statistical tests performed by the researchers found that patterns of the observed impacts closely paralleled temperature trends over the Earth—to an extent that they were beyond natural variability. Consequently, the researchers concluded that these observed global trends were caused primarily by human activities. Specifically, the Rosenzweig team linked the increase in global temperatures from 1970 to 2004 to impacts of physical and biological systems caused, as a minor part, by the natural variation of the Earth (natural events) and, as a major part, by the activities of humans (artificial events). What did the lead researcher from NASA say about their results? Please read on. << First page <   1 2 Next page > Last page - Post your comment >>

 

< Next story in category		Previous story in the category >