Humans have done enough evil to the mother nature. Long-term climate records from the Arctic provide strong new evidence that human-caused global warming can override Earth’s natural heating and cooling cycles.
For more than 2,000 years, a natural wobble in Earth’s axis has caused the Arctic region to move farther away from the sun during the region’s summer, reducing the amount of solar radiation it receives. The Arctic is now 600,000 miles farther from the sun than it was in AD 1, and temperatures there should have fallen a little more than 1 degree Fahrenheit since then.
Not only was the last half-century the warmest of the last 2,000 years, “but it reversed the long-term, millennial-scale trend toward cooler temperatures,” Kaufman said.
But then something else happened — Human Torture. The Science researchers found that during the 20th century, as human beings began pouring greenhouse gases into the atmosphere, the Arctic stopped cooling and started warming. Even though the Arctic is still gradually getting less sunlight, it’s still getting hotter — summer temperatures in the Arctic are 1.4 degrees C higher than they would have been if the cooling had continued unabated, according to the study. The most recent decade recorded — from 1999 to 2008 — was the warmest of the past 2,000 years. The recent warming trend has been so strong that researchers say it might have even kept the Earth from slipping into a new Ice Age — although now, of course, the world needs to deal with the opposite problem. The region has warmed 2.2 degrees since 1900 alone.
Another study released this week by the World Wildlife Fund (WWF) examines that problem and its potential future effects — and it’s not pretty. The WWF researchers found that Arctic sea ice is melting at a faster rate than expected, and that the massive land sheets in Greenland and parts of Antarctic are vulnerable. The report predicts that global sea level will rise more than 3 ft. by 2100, significantly higher than scientists had previously believed. “What we’re finding is truly sobering,” says Martin Sommerkorn, the senior adviser for the WWF’s Arctic Program.
Root cause
The root cause of the slow cooling was the orbital “wobble” that slowly varies, over thousands of years, the month in which the Earth approaches closest to the Sun.
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This wobble slowly decreased the total amount of solar energy arriving in the Arctic region in summertime, and the temperature responded – until greenhouse warming took over.
“The 20th Century is the first century for which how much energy we’re getting from the Sun is no longer the most important thing governing the temperature of the Arctic,” said another of the study team, Nicholas McKay from the University of Arizona.
The recent warming of the Arctic has manifested itself most clearly in the drastic shrinkage in summer sea-ice extent, with the smallest area in the satellite era documented in 2007.
As the Science study emerged, UN Secretary-General Ban Ki-moon was telling the World Climate Conference in Geneva that many of the “more distant scenarios” forecast by climate scientists were “happening now”.
Earlier this week, Mr Ban visited the Arctic in an attempt to gain first-hand experience of how the region is changing.
“Scientists have been accused for years of scaremongering. But the real scaremongers are those who say we cannot afford climate action,” he said in his Geneva speech, calling for world leaders to make bigger pledges of action in the run-up to December’s UN climate summit in Copenhagen.
The study also found that the methane locked in Arctic permafrost is increasingly at risk of being released if warming continues — a positive feedback cycle that would accelerate climate change. But the impacts of a hotter Arctic go beyond that. The WWF study found that as the Arctic warms, it could alter weather patterns beyond its borders, affecting temperature and rain patterns in Europe and North America. “The Arctic is the global refrigerator for the climate system,” says Sommerkorn. “Change it, and you might see even more dry summers in the Southwest and wetter winters in the Mediterranean.” It’s another reminder that in this season of climate change politics, we’re running out of time to make a difference.
Scientists have been debating how high the oceans will rise, but many say an increase of 6 to 9 feet is not out of the question if greenhouse gas release continues at the current rate.
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