Phanerozoic Chemical Weathering, CO2 Budgets and Global Climate

长期的全球碳循环模型缺乏地理维度；模型的输入和输出被限制在全球平均值。百万年时间尺度上的气候变化可以由大陆及其风化岩性的重新分布驱动(因为这会影响大气中的二氧化碳)。这个项目将通过执行几个新的气候模拟来探索显生宙气候变化的本质。S在同一时间段不同二氧化碳分压下的运行将阐明全球气温和径流之间的关系(这是影响化学风化速率的两个最重要的变量，从而影响二氧化碳分压)。然后，这些气候变量将被用于计算全球风化速率，使用我们之前研究期间绘制的古地质图。此外，还将评估另外两个重要因素，即地形(起伏)和化学风化速率的生物增强，使用对土壤和河流化学的影响的现代观测，并通过组合和重建古植物地理学。这项研究的目标是建立一个现实的、耦合的气候和生物地球化学循环模型，可以用来研究显生界气候的地理和时间变异性。

Models of the long-term, global carbon cycle have lacked a geographic dimension; model input and output have been restricted to global-mean values. Climate change on million-year time scales can be driven by redistribution of the continents and their weathering lithologies (as this affects atmospheric pCO2). This project will explore the nature of Phanerozoic climate change by performing several new climate simulations. Runs at different pCO2's for the same time periods will elucidate the relationship between global temperature and runoff (the two most important variables affecting chemical weathering rates and thus pCO2). These climate variables will then be used in calculations of global weathering rates, using paleogeologic maps prepared during our previous research. In addition, two other important factors, topography (relief) and biological enhancement of chemical weathering rates, will be assessed, using present-day observations of their affect on soil and stream chemistry, and by assembling and reconstructing paleophytogeographies. The goal of this research is to create a realistic, coupled model of climate and biogeochemical cycles that can be used to investigate the geographic and temporal variability of Phanerozoic climate.