<tt id="6hsgl"><pre id="6hsgl"><pre id="6hsgl"></pre></pre></tt>
          <nav id="6hsgl"><th id="6hsgl"></th></nav>
          国产免费网站看v片元遮挡,一亚洲一区二区中文字幕,波多野结衣一区二区免费视频,天天色综网,久久综合给合久久狠狠狠,男人的天堂av一二三区,午夜福利看片在线观看,亚洲中文字幕在线无码一区二区
             

          Global warming to alter California landscape

          (Agencies)
          Updated: 2007-12-30 11:37

          Related readings:
          2007 a year of weather records in US
          Global warming speeds ice melting
          US experts insist global warming not man-made
          Penguin species threatened warming
          Global warming 'will destroy Amazon'

          "They could be wiped out of California depending on how quickly the change happens," said Cameron Barrows, who studies the effects of climate change for the Center for Conservation Biology in Riverside.

          Farther north, where wet, cold winters are crucial for the water supply of the entire state, warmer temperatures will lead to more rain than snow in the Sierra Nevada and faster melting in the spring.

          Because 35 percent of the state's water supply is stored annually in the Sierra snowpack, changes to that hydrologic system will lead to far-reaching consequences for California and its ever-growing population.

          Some transformations already are apparent, from the Sierra high country to the great valleys that have made California the nation's top agricultural state.

          The snow line is receding, as it is in many other alpine regions around the world. Throughout the 400-mile-long Sierra, trees are under stress, leading scientists to speculate that the mix of flora could change significantly as the climate warms. The death rate of fir and pine trees has accelerated over the past two decades.

          In the central and southern Sierra, the giant sequoias that are among the biggest living things on Earth might be imperiled.

          "I suspect as things get warmer, we'll start seeing sequoias just die on their feet where their foliage turns brown," said Nate Stephenson, a US Geological Survey ecologist who is studying the effects of climate change in the Sierra Nevada. "Even if they don't die of drought stress, just think of the wildfires. If you dry out that vegetation, they're going to be so much more flammable."

          Changes in the mountain snowpack could lead to expensive water disputes between cities and farmers. Without consistent water from rivers draining the melting snow, farmers in the Central and Salinas valleys could lose as much as a quarter of their water supply.

          Any drastic changes to the state's $30 billion agriculture industry would have national implications, since California's fertile valleys provide half the country's fresh fruits, nuts and vegetables, according to the Union of Concerned Scientists' study.

             1 2 3   


          Top World News  
          Today's Top News  
          Most Commented/Read Stories in 48 Hours
          主站蜘蛛池模板: 精品一区二区三区在线播放视频| 精品亚洲国产成人| A毛片终身免费观看网站| 美女禁区a级全片免费观看| 国产精品无码a∨麻豆| 精品亚洲精品日韩精品| 国产一区日韩二区欧美三区| 久久精品免视看国产成人| 欧美日韩精品一区二区视频| 无码人妻aⅴ一区二区三区蜜桃| 香港日本三级亚洲三级| 99在线视频免费观看| 久久天堂无码av网站| 姝姝窝人体色WWW在线观看| 尤物视频在线播放你懂的| 国产成人精品日本亚洲第一区| 国产91专区一区二区| 中国xxxx真实偷拍| 免费网站看V片在线毛| 厨房与子乱在线观看| 国产精品激情av在线播放| 国产av一区二区三区久久| 黑人大荫道bbwbbb高潮潮喷| 亚洲 一区二区 在线| 色欲综合久久中文字幕网| 国产精品午夜福利合集| 一区二区和激情视频| 亚洲色大成网站WWW永久麻豆| 久久综合国产色美利坚| 又大又硬又爽免费视频| 亚洲AV成人片在线观看| 亚洲精品国产综合久久一线| 亚洲国产午夜精品理论片| 亚洲天堂亚洲天堂亚洲天堂| 99久久无码私人网站| 亚洲av永久无码精品成人| 高清无码午夜福利视频| 一边摸一边做爽的视频17国产| 韩国午夜福利片在线观看| 人妻日韩精品中文字幕| 亚洲色成人一区二区三区人人澡人人妻人人爽人人蜜桃麻豆 |