Climate change already taking biological toll
Two studies published in this week's issue of the journal Nature show that the geographical range of species is shifting. The results confirm the observations of many field biologists that climate change is already having a serious impact on living systems.
US researchers Camille Parmesan and Gary Yohe analysed previous studies of more than 1,700 species. They found that on average species had shifted around 6 kilometres per decade towards the poles. The research also shows that 'spring' is arriving earlier as the years go by, with events such as migration and egg-laying in birds advancing by 2.3 days per decade.
"[The results implicate] climate change as an important driving force on natural systems," say Parmesan and Yohe.
A separate analysis of 143 studies comes to a similar conclusion. Terry Root of Stanford University, United States and colleagues found that species from insects to mammals, and grasses to trees have shifted their geographical ranges in line with recent temperature changes. The shift was most marked at high latitudes and altitudes, where the largest temperature changes are predicted.
"If such climatic and ecological changes are now being detected when the globe has warmed by an estimated average of only 0.6°C [over the past 100 years], many more far-reaching effects on species and ecosystems will probably occur in response to changes in temperature to levels predicted … which run as high as 6°C by 2100," the study warns.
The biological impact of global climate change has been one of the most divisive topics to face the Intergovernmental Panel on Climate Change, the body set up to assess scientific information on climate change.
Root's team urges the scientific community to increase its understanding of the responses of plants and animals to changing climate. "This understanding, coupled with further documentation of change, may well indicate a need for actions to modify conservation efforts and future planning to account for climate change, and to slow the projected rate of warming."
Source: © SciDev.Net 2003
Link to paper by Camille Parmesan and Gary Yohe
Link to paper by Terry Root et al