Late Pliocene soils and lakes: A global data set for the analysis of climate feedbacks in a warmer world

在人类温室气体排放量不断增加的情况下，我们对未来全球变暖的理解在很大程度上依赖于气候模型模拟的预测。尽管气候模型逐渐变得更加复杂，但在模拟气温和大气二氧化碳浓度在最近前所未有的气候时，气候模型具有不确定性。土壤、湖泊和植被可能会对气候系统产生强烈影响，并且往往是模拟实验中不确定性的关键因素。探索不确定性和了解未来潜在气候变化机制的一种方法是查看过去的时间段，即可获得的地质数据。拟议中的项目将通过综合地质记录中的全球数据集，调查土壤和湖泊在变暖、高二氧化碳世界中的重要性。我们将重点放在上新世晚期，距今约360万-260万年前。随着全球平均气温的升高和大气中二氧化碳浓度的升高，上新世晚期地质期提供了“一个在许多方面与模型估计的21世纪末的地球相似的可接近的世界的例子”(政府间气候变化专门委员会，2007)。我们新的全球土壤和湖泊数据集将被用作古气候模拟实验的边界条件。然后，将使用现有的综合TEVIS数据集(第三纪环境和植被信息系统)对这些模型的结果进行评估，该数据集包含来自202个古植物学地点的数据。通过指出弱点和优势，我们的数据模型比较将测试土壤和湖泊在高二氧化碳气候系统中的重要性，并将有助于改进我们所依赖的气候模型，以模拟未来的气候变化。

Our understanding of future global warming under increasing human-related emissions of greenhouse gases relies heavily on prediction of climate model simulations. Although progressively more sophisticated, climate models have uncertainties in particular when simulating climates with temperatures and atmospheric CO2 concentrations unprecedented in the recent past. Soils, lakes and vegetation can have a strong impact on the climate system and are often key factors for uncertainties in modelling experiments. One approach to explore uncertainties and understand mechanisms of potential future climate change is to look at time periods in the past, for which geological data are available. The proposed project will investigate the importance of soil and lakes in a warmer, high CO2 world, by synthesising global datasets from geological records. We will focus on the Late Pliocene geological period, ca. 3.6-2.6 million years ago. With increased mean global temperatures and higher atmospheric CO2 concentrations, the late Pliocene geological period provides an 'accessible example of a world that is similar in many respects to what models estimate could be the Earth of the late 21st century' (Intergovernmental Panel on Climate Change 2007). Our new global soil and lake dataset will be used as boundary conditions in palaeoclimate modelling experiments. The outcomes of these models will then be evaluated using the existing comprehensive TEVIS dataset (Tertiary Environment and Vegetation Information System), which contains data from 202 palaeobotanical sites. By indicating weaknesses and strengths, our data-model comparison will test the importance of soils and lakes in high CO2 climate systems and will contribute to the improvement of climate models that we rely upon for simulating future climate change.