男女羞羞视频在线观看,国产精品黄色免费,麻豆91在线视频,美女被羞羞免费软件下载,国产的一级片,亚洲熟色妇,天天操夜夜摸,一区二区三区在线电影

Science and Health

Iceberg move reveals secrets of marine life

By Pauline Askin (China Daily)
Updated: 2011-04-18 08:04
Large Medium Small

Iceberg move reveals secrets of marine life

SYDNEY - An iceberg's crash into an Antarctic glacier last year cracked off a huge swathe of ice, bringing to light a vast span of the Southern Ocean and providing scientists with a chance to conduct experiments that may help understand climate change.

The incident, in which the iceberg clipped the Mertz Glacier in East Antarctica and broke off nearly 78 kilometer of glacier tongue, exposed a section of ocean water previously covered in hundreds of meters of ice and brought to light marine life including sea stars as big as hubcaps.

"Suddenly the geometry of Antarctica has changed," said Steve Rintoul, an oceanographer with the Antarctic Climate and Ecosystems Cooperative Research Centre at the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Tasmania.

"It was a sort of natural experiment, where the calving of the glacier tongue was not caused by climate change. This is a natural event, so nature has done the experiment for us this time."

A team of 40 Australian and international scientists, including Rintoul, visited the region during the Antarctic summer to study the impact of the calving.

Among the unanticipated biological results was the release of about 10,000 square meters of ice into the ocean when it drifted off into warmer water.

Its consequent melting decreased water salinity and sparked an intense bloom of phytoplankton. The plants need light and nutrients to grow, along with small amounts of iron, which usually comes as dust falling from the sky.

"The old ice had accumulated decades of iron dust supply, and when it broke off and melted seems to have provided the phytoplankton with between 20 and 40 years' dose of iron in a single season," Rintoul said.

Another side effect, combined with clearer water, was the exposure of sea animals including giant seastars, colorful sponges and feathery sea pens, revealed after decades in dark Antarctic waters.

Overall, researchers ended up with an unprecedented chance to test theories of how the marine ecosystem might respond to such large-scale changes, a possible foretaste of what could lie ahead with climate change.

"Some of the areas we sampled have been under ice for many decades so no ship has ever reached that area," Rintoul added.

Reuters

分享按鈕
主站蜘蛛池模板: 西安市| 康保县| 彩票| 阳东县| 万荣县| 杭锦旗| 卓尼县| 沙湾县| 青州市| 安吉县| 专栏| 商城县| 莫力| 江西省| 平顶山市| 河东区| 太和县| 商城县| 万载县| 蒙城县| 闵行区| 巴东县| 津市市| 陈巴尔虎旗| 雷州市| 吉隆县| 英德市| 西丰县| 合作市| 宝鸡市| 广平县| 南郑县| 绥化市| 登封市| 营口市| 东城区| 米泉市| 桦川县| 黑龙江省| 海口市| 新干县| 民勤县| 习水县| 龙海市| 阜宁县| 长沙县| 离岛区| 河西区| 梅河口市| 宁乡县| 额济纳旗| 宁远县| 阿尔山市| 辽阳县| 尤溪县| 双城市| 依兰县| 新晃| 贺州市| 徐汇区| 宁强县| 麻栗坡县| 兴化市| 佛冈县| 墨江| 樟树市| 张家界市| 南岸区| 鹤庆县| 孟津县| 丰顺县| 孟津县| 梧州市| 长泰县| 枣强县| 资源县| 栖霞市| 桑日县| 兴和县| 金乡县| 驻马店市| 普安县|