[ti:Study Suggests Earth Is Losing Ice Faster than in Mid-1990s]
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[00:00.04]New research suggests Earth's ice
[00:03.32]is melting faster today than in the 1990s.
[00:09.32]An estimated 28 trillion metric tons of ice
[00:14.20]have melted away from the world's sea ice,
[00:18.04]ice sheets and glaciers since the middle of the 1990s.
[00:25.28]The yearly melt rate is now about 57 percent faster
[00:30.64]than it was 30 years ago.
[00:34.76]Scientists reported the findings
[00:37.88]in a study published in The Cryosphere.
[00:42.64]"It was a surprise to see such a large increase in just 30 years,"
[00:48.76]said study co-author Thomas Slater.
[00:53.80]He is a glaciologist, a scientist who studies glaciers,
[00:58.76]at Leeds University in Britain.
[01:02.96]Slater noted that the ice melt situation
[01:06.52]is clear to those who depend on mountain glaciers
[01:10.36]for drinking water.
[01:13.00]It is also clear to those who depend on winter sea ice
[01:17.68]to protect coastal homes from storms.
[01:22.80]But Slater noted that the world's ice melt has now started
[01:27.72]to be recognized even far from frozen areas.
[01:33.32]"People do recognize that, although the ice is far away,
[01:38.60]the effects of the melting will be felt by them," he said.
[01:44.28]The melting of land ice – on Antarctica, Greenland
[01:48.84]and mountain glaciers – added enough water to the ocean
[01:53.44]during the 30-year time period
[01:55.76]to raise the average worldwide sea level by 3.5 centimeters.
[02:03.96]Ice loss from mountain glaciers made up 22 percent
[02:08.92]of the yearly ice loss totals.
[02:12.80]Across the Arctic, sea ice is also shrinking
[02:17.08]to new summertime lows.
[02:20.52]Last year saw the second-lowest levels of sea ice
[02:25.12]in more than 40 years.
[02:28.40]As sea ice melts, it uncovers dark water which takes in solar radiation,
[02:36.12]rather than sending it back out of the atmosphere.
[02:40.96]This is known as Arctic amplification,
[02:44.96]which increases area temperatures even further.
[02:50.36]The worldwide atmospheric temperature has risen
[02:54.12]by about 1.1 degrees Celsius since pre-industrial times.
[03:00.72]But in the Arctic, the warming rate has been more than
[03:04.56]twice the world average in the last 30 years.
[03:10.40]The team of British scientists studied satellite data
[03:14.84]from 1994-2017, used site measurements
[03:20.20]and created computer models to measure the ice melt.
[03:25.56]They found that the world was losing an average
[03:29.12]of 0.8 trillion metric tons of ice per year in the 1990s.
[03:36.84]In recent years, the team estimated a loss
[03:40.56]of about 1.2 trillion metric tons each year.
[03:46.36]Gabriel Wolken is a geologist with the Alaska Division
[03:50.92]of Geological and Geophysical Surveys.
[03:55.48]He said that finding even an estimated ice loss total
[04:00.60]from the world's ice formations is "a really interesting approach,
[04:05.60]and one that's actually quite needed."
[04:10.60]Wolken was a co-author of the 2020 Arctic Report Card
[04:15.40]released in December, but was not involved with the new study.
[04:22.24]He said that in Alaska, people are very mindful of glacial ice loss.
[04:29.96]"You can see the changes with the human eye," he added.
[04:36.00]I'm Jonathan Evans. 更多听力请访问21VOA.COM