5 October 2009
Temperatures in the Arctic are now the highest they've been for 2,000 years, according to scientists. Researchers in the United States say that it is one of the clearest signs yet that human activity is warming the planet.
Click to hear the report:
Scientists have produced evidence showing dramatically that the current temperature rise there is highly unusual. For most of the last two thousand years, the Arctic slowly cooled, a consequence of variations in the Earth's orbit.
But over the last century, the cooling abruptly reversed, and the region is now warmer than at any time in the 2,000 year record. Writing in the journal Science, the researchers say this shows how quickly the Arctic responds to climatic changes.
Richard Black, BBC News
Click to hear the vocabulary:
- produced evidence
found and shown proof
here, in a very convincing way (literally, dramatically means very noticeably)
- a consequence
one of the results
slight changes; here, deviations from the average moving path of astronomical objects, e.g. a planet or satellite
the curved path through which astronomical objects move around a planet or star
changed to its opposite
- responds to
here, is affected by
- climatic changes
long-term changes in weather patterns