Collaborative Research: Carbon-Climate Interactions with Increasing Water Demand

该项目计划通过数值模拟实验研究一系列假设，将全球的碳和水循环联系起来，把陆地和海洋联系起来，把低纬度和高纬度联系起来。假设是：1)夏季干旱在年际时间尺度上是由环流和水汽输送的变化引起的。2)生态系统对干旱的适应能力因生态系统类型和结构的不同而不同，因此十年平均碳汇和碳-气候反馈的大小与干旱的频率和持续时间有关。3)区域气候变暖导致陆地径流和降水的变化将增加亚极地和北极环境中的上层海洋层化，导致海洋二氧化碳(CO2)吸收减少。4)21世纪地表变化和不断增加的水资源需求将加剧干旱状况，增加碳-气候反馈，加速全球变暖。该项目将在国家大气研究中心(NCAR)社区气候系统模式的框架内使用一系列完全耦合的碳-气候模式模拟。该项目将举办一个关于生物地球化学-气候模型耦合的多学科研究生暑期学校，并将为高中生开发和测试环境科学教学模块。

This project plans to investigate a series of hypotheses via numerical modeling experiments linking carbon and hydrologic cycles across the globe, linking land and ocean, low and high latitudes. The hypotheses are: 1) Summertime droughts on interannual time-scales arise from changes in circulation and the delivery of moisture. 2) The resilience of ecosystems to droughts varies with ecosystem type and structure, so that the magnitude of the decadal-mean carbon sink and carbon-climate feedback is related to the frequency and duration of droughts. 3) Regional, climate warming driven changes in terrestrial runoff and precipitation will increase upper ocean stratification in subpolar and Arctic environments resulting in decreased ocean carbon dioxide (CO2) uptake. 4) Land surface modifications and increasing water demands of the 21st century will amplify drought conditions, increase carbon-climate feedbacks and accelerate global warming.The project will use a series of fully coupled carbon-climate model simulations in the framework of the National Center for Atmospheric Research (NCAR) Community Climate System Model. The project will host a multi-disciplinary graduate student summer school on Coupled Biogeochemistry-Climate Modeling and will develop and test teaching modules in environmental science for high school students.