P2C2: A Network of Paleo-Monsoon Rainfall Stations in Southeast Asia to Investigate Atmospheric Circulation Changes over the Past Four Centuries

提供资金支持开发和校准一种从泰国各地生长的树木年轮中提取的纤维素重建雨水三角洲氧-18的方法。研究人员将测量卡西松和梅库斯松的δ氧-18树纤维素，作为重建东南亚地区大气降水年至次年记录的一种手段。研究人员假设，来自印度洋的水分增加是对东南亚大陆季风槽向东扩张的反应。为了验证这一假设，研究人员将把松三角洲氧-18的数据库扩展到东南亚各地，以绘制降水三角洲氧-18变化的空间格局。该项目有望帮助开展热带树木年轮气候分析。这一点很重要，因为目前热带树木不能作为可靠的古气候档案，因为它们不像高纬度地区的标本那样记录可见的季节性树木年轮。开发热带树木的同位素技术将是气候分析的一个变革性突破。

Funding is provided to support the development and calibration of a method for reconstructing rainwater delta Oxygen-18 from cellulose extracted from the annual rings of trees that grow throughout Thailand. The researchers will measure delta Oxygen-18 tree cellulose from Khasi pine and Merkus pine trees as a means to reconstruct annual to subannual records of atmospheric precipitation at sites across Southeast (SE) Asia. The researchers hypothesize that the increased moisture from the Indian Ocean is a response to the expansion of the continental monsoon trough eastward over SE Asia. To test this hypothesis, the researchers will extend the data base of Pine delta Oxygen-18 to sites across SE Asia in order to map the spatial pattern of precipitation delta Oxygen-18 variability.The project offers the promise of helping opening tropical tree-rings to climate analysis. This is important because, at present, tropical tree cannot be used as a reliable paleoclimate archive because they do not lay down visible seasonal tree rings as do higher latitude specimens. Developing an isotopic technique for tropical trees would be a transformative breakthrough in climate analysis.