Nov 14, 2003
Detection of a Human Influence on North American Climate
by
,
Science
- Uses several indices of large-scale patterns of surface temperature variation to investigate climate change in North America over the 20th century
- Simulates the observed variability of these indices using a number of climate models
- Comparison of index trends in observations and model simulations shows that North American temperature changes from 1950 to 1999 were unlikely to be due to natural climate variation alone
- Finds that observed trends over this period are consistent with simulations that include anthropogenic forcing from increasing atmospheric greenhouse gases and sulfate aerosols
- Finds, however, that most of the observed warming from 1900 to 1949 was likely due to natural climate variation