质量和体积对20世纪全球海平面上升的贡献
Laury Miller1, Bruce C Douglas
1Laboratory for Satellite Altimetry, NESDIS, NOAA, Silver Spring, Maryland 20910, USA. laury.miller@noaa.gov
Nature
|March 26, 2004
概括
全球海平面上升估计来自潮计的估计高于海洋变暖的估计. 这项研究表明,冰盖融化,而不是热膨胀,是20世纪海平面上升的主要驱动因素.
科学领域:
- * 气候科学 气候科学
- * 海洋学 海洋学
- * * 冰川学 冰川学
背景情况:
- *二十世纪全球海平面上升受到争议,潮数据 (1.5-2.0毫米/年) 与间接估计相冲突.
- * 间接估计,海平面上升归因于海洋热膨胀 (约. 0.5 mm yr-1) 和冰融,而冰融的贡献被认为较小.
- *差异表明潮计数据膨胀或低估了质量/体积变化贡献.
研究的目的:
- * 调和全球海平面上升速度及其原因的相互矛盾的估计.
- * 调查海洋变暖和冰川融化对海平面上升的相对贡献.
- *为了验证与海洋学数据的潮计测量.
主要方法:
- *分析潮计海平面测量结果.
- * 整合了来自太平洋和大西洋的海洋温度和盐度数据.
- * 测量尺度决定的海平面上升与来自海洋学数据的体积变化率的比较.
主要成果:
- *海平面上升的速度是测量尺度决定的,比温度/盐度数据的体积变化速度高出2-3倍.
- *这些发现支持以前的估计,为20世纪海平面上升的1.5-2.0毫米/年.
- * 由于冰川融化而增加的质量被认为比海洋变暖更为重要的贡献者.
结论:
- *潮计数据准确地反映了导致海平面上升的综合质量和体积变化.
- * 大陆冰融对20世纪全球海平面上升的贡献很大.
- * 海洋变暖在20世纪海平面上升中的作用可能不如以前估计的那么重要.
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