Doctoral Dissertation Research: Global Fire Since the Last Glacial Maximum

博士论文研究：末次盛冰期以来的全球火灾

• 批准号: 0727424
• 负责人: Patrick Bartlein
• 金额: $ 0.76万
• 依托单位: University of Oregon Eugene
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-07-15 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0727424&HistoricalAwards=false
• 关键词: Doctoral; Dissertation; Research; Global; Fire

Wildfire activity has been unusually extreme in many parts of the world in recent years. These broadscale changes in fire regimes pose a significant threat to human health, ecosystems, and the global climate system. It is difficult to understand how and why these changes are occurring without long-term, global fire-history data. Satellite images, historical records, and dendrochronological data have been used to create short histories of up to 100 years in duration, but no spatially explicit syntheses exist for longer time periods. This doctoral dissertation research project will compile and synthesize published charcoal data to reconstruct global fire activity since the last glacial maximum. The doctoral candidate will examine changes in biomass burning during periods of both gradual and abrupt climate change and compare paleofire and pollen data to investigate long-term fire, vegetation, and climate dynamics. More specifically, she will create a global database of charcoal-based paleofire records that spans the last 21,000 years; perform a meta-analysis of the highest-resolution paleofire records, which are concentrated in North America; integrate charcoal and pollen data from North America to examine fire and fuel relationships under changing climate conditions; and use observed and simulated paleofire data to make a global data-model comparison of fire activity at the time of the last glacial maximum and during the mid-Holocene.Results from this study will enhance basic understanding of the spatial and temporal patterns of fire activity and of the mechanisms behind major shifts in fire regimes that have occurred since the last glacial maximum. The detailed analysis of high-resolution charcoal data and pollen data will provide new insights into specific dimensions of fire-regime changes, such as how fire frequency versus fire severity have varied across climate and vegetation gradients. The data-model comparisons will validate a coupled vegetation-fire model and provide a new tool for testing hypotheses about interactions between fire, climate, vegetation and human activities. Data will be shared with the International Multiproxy Paleofire Database sponsored by the World Data Center for Paleoclimatology at NOAA. As a Doctoral Dissertation Research Improvement award, this award also will provide support to enable a promising student to establish a strong independent research career.

近年来，在世界许多地方，野火活动异常极端。 火灾制度的这些广泛变化对人类健康，生态系统和全球气候系统构成了重大威胁。 如果没有长期的全球火灾历史数据，这些变化是如何以及为什么发生的。 卫星图像，历史记录和Dendrocologoly数据已被用来创建长达100年的短期历史，但在更长的时间段内没有空间明确的合成。 该博士学位论文研究项目将自上次冰川最大值以来重建已发表的木炭数据，以重建全球火灾活动。 博士候选人将检查逐渐和突然的气候变化时期生物量燃烧的变化，并比较古呼和花粉数据，以研究长期火灾，植被和气候动态。 更具体地说，她将创建一个涵盖过去21，000年的基于木炭的古拨记记录的全球数据库；对北美的最高分辨率古雷记录进行荟萃分析；整合来自北美的木炭和花粉数据，以检查气候条件不断变化的火灾和燃料关系；并使用观察到的和模拟的古拨动数据在上次冰川最大值时和中期期间对火灾活动进行全球数据模型比较。这项研究的反应将增强对火灾活动的空间和空间机制的基本理解，以及自从最后一次熟悉冰川效果以来发生的火灾方案的机制。 对高分辨率木炭数据和花粉数据的详细分析将为火力期变化的特定维度提供新的见解，例如在气候和植被梯度中，火频率与火灾的严重程度如何变化。 数据模型比较将验证耦合的植被模型，并为测试有关火灾，气候，植被和人类活动之间相互作用的假设提供新工具。 数据将与NOAA的世界数据中心赞助的国际多X型古发数据库共享。 作为博士学位论文研究改进奖，该奖项还将提供支持，使有前途的学生能够建立强大的独立研究职业。