微观地震学证据表明,大西洋东北部的波浪气候在不断变化,大西洋东北部的波浪气候在不断变化
I Grevemeyer1, R Herber, H H Essen
1Department of Earth Sciences, University of Bremen, Germany. ingo@geophys2.uni-bremen.de
Nature
|December 1, 2000
概括
气候变化可能会增加海洋波浪的高度. 一项长达40年的关于微地震的研究,即与海洋波相关的地面振动,显示在过去20年里,东北大西洋的波浪活动翻了一番.
科学领域:
- 地质物理学 地质物理学
- 海洋学 海洋学 海洋学
- 气候科学 气候科学
背景情况:
- 海平面上升和波浪高度增加对沿海地区和海洋产业构成威胁.
- 长期气候变化检测受到观察数据不一致的阻碍.
- 微震,四至十六秒周期的地震振动,与海洋波动活动相关.
研究的目的:
- 为了重建东北大西洋的波浪气候.
- 为了研究过去40年波浪高度的潜在趋势.
- 评估微地震数据与气候变化指标之间的联系.
主要方法:
- 利用来自德国汉堡的冬季微地震的40年连续记录.
- 分析了微地震数据,以确定强烈地震活动的时期.
- 与历史气候数据相关的微地震趋势,包括空气温度和风暴强度.
主要成果:
- 从1954年到1977年,每个月平均检测到七天强烈的微地震活动,没有显著的趋势.
- 在记录后半部分观察到强微地震活动的显著增加,达到每月大约14天.
- 重建的波浪气候表明,过去20年来,东北大西洋的波浪活动翻了一番.
结论:
- 这项研究提供了证据,表明过去二十年来,东北大西洋的波浪高度显著增加.
- 波浪活动的增加与地表空气温度的上升以及该地区风暴的增加并行.
- 这些发现表明,一个共同的气候强迫机制推动了海浪高度的增加和区域变暖.
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