Evidence has found that indicates that rates of forest destruction in the Brazilian Amazon have accelerated over the last decade. A research team led by William Laurance of the Smithsonian Tropical Research Institute, analyzed deforestation estimates produced by Brazil's National Space Agency that were based on detailed satellite images of the Amazon since 1978.
Contrary to the claims of the Brazilian government that threats to Amazonian forests have fallen in recent years because of improved environmental laws and public attitudes, the Smithsonian team asserts that rates of deforestation have risen sharply since 1995. "Forest destruction from 1995 to 2000 averaged almost two million hectares a year," said Laurance. "That's equivalent to seven football field a minute, and it's comparable to the bad old days in the 1970s and 1980s, when forest loss in the Amazon was catastrophic."
Although new environmental laws in Brazil are designed to slow forest loss, the research team claims that most laws are rarely enforced. That, in concert with a rapidly growing population and dramatically expanding logging and mining industries, means that threats to Amazonian forests are growing.
The loss of forested areas influences global warming - a problem that is believed to affect virtually all areas of the world to a greater or lesser extent. Northern climates are believed to be among the most vulnerable to global warming. It would seem a logical extension of that idea to believe that the southern polar area would be another area where global warming is most pronounced. Evidence presented by researchers with the National Science Foundation indicates that is not the case.
They claim that Antarctica overall has cooled measurably during the last 35 years - despite a global average increase in air temperature of 0.6 degrees celsius during the 20th century. A 14-year continuous weather station record from the shore of Lake Hoare reveals that seasonally averaged surface air temperature has decreased by 0.7 degrees celsius per decade. The temperature decrease is most pronounced in summer and autumn.
Other studies conducted in Antarctica have deduced a warming trend elsewhere in the continent - between 1958 and 1978. The researchers responsible for the latest study also claim that data showing that the Antarctic is warming may have been skewed because the measurements were taken largely on the Antarctic Peninsula, which extends northwards toward South America.
The Peninsula itself is warming dramatically, the researchers note, and there are many more weather stations on the Peninsula than elsewhere on the continent. If you remove the Peninsula from the data set, the remaining temperature records indicate that the majority of Antarctica is cooling.