Evolution of ENSO during the Holocene

全新世ENSO的演变

• 批准号: 0352044
• 负责人: Richard Fairbanks
• 金额: $ 16万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-05-01 至 2006-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0352044&HistoricalAwards=false
• 关键词: Evolution; ENSO; during; Holocene

Under this award the PIs will drill the reef at Tarawa Atoll (1N, 172E) in the central tropical Pacific in attempt to reconstruct El Nino/La Nina (ENSO) variability over the past 10K years. The PIs propose to measure sea surface salinity and temperature based on the 18O geochemical proxy. The PIs pilot study at Tarawa Atoll shows that typical ENSO events occurred as early at 7,760 years before present, during a time when some researchers say they did not detect evidence for ENSO in Ecuador lake sediments. ENSO tropical Pacific ocean/atmosphere anomalies are a dominant source of global climate variability, sometimes having catastrophic consequences. Instrumental data and intermediate and coupled models indicate that decadal and possibly millennial-scale sea surface temperature variability in the tropical Pacific have similar anomaly patterns to the El Nino/La Nina anomaly fields. A remarkable finding that the ENSO fluctuations of ocean/climate change were absent in terrestrial climate proxy records between 5,000 and 12,000 years before present has sparked new research in the ENSO modeling and paleoceanographic communities. Climate data for the past century show that some regions have changed their climate response to ENSO, as the frequency and intensity of tropical Pacific anomalies changed.

根据该奖项，PI将在热带太平洋中部的塔拉瓦环礁（1 N，172 E）钻探珊瑚礁，试图重建过去1万年的厄尔尼诺/拉尼娜（ENSO）变化。PI建议根据18 O地球化学代用指标测量海表盐度和温度。在塔拉瓦环礁进行的初步研究表明，典型的ENSO事件早在距今7,760年前就发生了，当时一些研究人员说，他们没有在厄瓜多尔湖泊沉积物中发现ENSO的证据。 厄尔尼诺/南方涛动热带太平洋海洋/大气异常是全球气候变率的主要来源，有时会造成灾难性后果。 仪器数据和中间和耦合模式表明，在热带太平洋的十年和可能的千年尺度的海表温度变率有类似的异常模式的厄尔尼诺/拉尼娜异常字段。 一个引人注目的发现是，海洋/气候变化的ENSO波动在距今5,000年至12,000年之间的陆地气候代用记录中不存在，这引发了ENSO建模和古海洋学界的新研究。 过去世纪的气候数据表明，随着热带太平洋异常的频率和强度发生变化，一些区域对ENSO的气候反应发生了变化。