Climate records from corals
Climate records from corals
复制标题
DOI：
10.1002/wcc.39
复制
发表时间：
2010-05
期刊：
影响因子：
--
通讯作者：
J. Lough
中科院分区：
文献类型：
--
作者：
J. Lough
热带海洋是全球气候系统的热机，对气候变率和热带海洋变化的性质和原因的了解受到仪器记录相对较短的限制。某些巨大的造礁珊瑚在其碳酸钙骨架中包含丰富的历史代用气候和环境信息。这些信息可以从活珊瑚中获得，这些活珊瑚可以长达几百年的历史，也可以从珊瑚化石中获得，这些珊瑚化石通常在死后保存得很好，可以追溯到更遥远的过去。这些珊瑚的连续、高分辨率（年度到季节性）信息是由一系列测量方法提供的，这些测量方法包括生长特征，可以记录珊瑚对异常环境条件的反应，以及各种地球化学示踪剂，这些示踪剂与骨骼的结合是由环境海水特征介导的。稳定氧同位素δ18O一直是最常用的测量珊瑚环境示踪剂，尽管它反映了海面温度和海水盐度，但该变量的长期记录为热带海洋的年际（例如El Niño‐南方涛动）、年代际和更长时间尺度的变化提供了新的见解——这些信息无法从仪器记录中获得——它补充了其他高分辨率代用气候信息来源(例如：树木年轮、冰芯、文献记录)。通过努力减少各种不确定性来源，珊瑚的替代气候记录对过去全球气候图景的贡献正在得到加强，这些不确定性来源可能会混淆任何替代气候信息来源的解释。版权所有©2010 John Wiley & Sons， Ltd
Understanding the nature and causes of climate variability and change in the tropical oceans—the heat engine of the global climate system—is limited by the relatively short length of instrumental records. Certain massive reef‐building corals contain a wealth of historical proxy climate and environmental information locked in their calcium carbonate skeletons. This information is available from living corals that can be up to several hundred years old and from fossil corals, often well preserved after death, for well‐dated windows of the more distant past. Continuous, high‐resolution (annual to seasonal) information from such corals is provided by a range of measures that include growth characteristics which can document coral responses to unusual environmental conditions and various geochemical tracers whose incorporation into the skeleton is mediated by ambient seawater characteristics. The stable oxygen isotope ratio, δ18O, has been the most commonly measured coral environmental tracer and, although reflecting both sea surface temperature and seawater salinity, long records of this variable are providing new insights into interannual (e.g., El Niño‐Southern Oscillation), decadal, and longer time‐scale variability in the tropical oceans—information not accessible from the instrumental records—which complements other sources of high‐resolution proxy climate information (e.g., tree rings, ice cores, documentary records). The contribution of proxy climate records in corals to the global picture of past climates is being enhanced through efforts to reduce the various sources of uncertainty that can confound the interpretation of any source of proxy climate information. Copyright © 2010 John Wiley & Sons, Ltd.