Arctic lakes help scientists understand climate change

摘要

A clearer picture of climate change is emerging from the sediment drawn from the bottom of Arctic lakes.rnAn international team of scientists, led by Darrell Kaufman, a Northern Arizona University professor of geology and environmental science, recently completed a five-year study that places the recent warming in the context of long-term climate change. Because this warming occurred abruptly during the 20th century while atmospheric greenhouse gases were accumulating, these findings provide additional evidence that humans are influencing climate.rnThe evidence was found by generating a 2000-year-long reconstruction of Arctic summer temperature using natural archives of climate change from tree rings, glacier ice and mostly from lake sediments from across the Arctic, a region that responds sensitively to global changes.