Improving the Understanding and Modeling of Land Processes in the Community Climate System Model (CCSM4.0)

陆地过程在地球系统中起着关键作用，其处理是气候系统模拟的关键。该项目的总体目标是提高社区气候系统模式（CCSM4.0）的新版本中的土地过程的理解和建模，其土地部分是社区土地模式（CLM4.0）。研究人员在NSF支持下取得了重大进展，解决了与陆地-大气-海洋界面过程相关的各种跨学科问题，如CLM4.0中实施的与陆地过程五个不同方面相关的改进参数化，欧洲中期天气预报中心（ECMWF）实施的海洋表面温度计划，以及在国家环境预测中心（NCEP）区域和全球预报模式中测试和实施他们关于动量和热量的陆面粗糙度长度的新公式。该项目将通过广泛的现场和卫星数据分析、过程研究和全球模拟来解决四个问题：a）CCSM4.0中的地表能量/水/碳循环和动态植被的真实性如何？B）CNDV（动态植被的碳和氮循环）如何影响CLM4.0中的能量/水/碳循环，如何进一步改善其处理？c）地下水如何影响CLM4.0中的其他土地过程，如何进一步改善其处理？以及d）如何利用从这些努力中获得的见解来更好地理解CCSM4.0对未来气候预测的不确定性？拟议工作的更广泛影响包括：a）提高对能源/水/碳循环的理解，改善两个重要过程的处理（即，（B）更新和维护用于跨学科研究的计算机集群;（c）通过同行评审的出版物、在会议和讲习班上的介绍、网页以及向公众的讲座，广泛传播研究成果。

Land processes play a key role in the earth system, and their treatment is crucial for climate system modeling. The overall goal of this project is to improve the understanding and modeling of land processes in the new version of the Community Climate System Model (CCSM4.0) whose land component is the Community Land Model (CLM4.0). The investigators build on their significant progress under prior NSF support in addressing various interdisciplinary issues related to the land-atmosphere-ocean interface processes, as evidenced by the implementation in CLM4.0 of their improved parameterizations related to five different aspects of land processes, the implementation in the European Centre for Medium-Range Weather Forecasts (ECMWF) of their ocean skin temperature scheme, and the testing and implementation of their new formulations of land surface roughness lengths for momentum and heat in the National Centers for Environmental Prediction (NCEP) regional and global forecasting models.This project will address four questions through extensive in situ and satellite data analysis, process studies, and global modeling: a) How realistic are the land surface energy/water/carbon cycles and dynamic vegetation from CCSM4.0? b) How does CNDV (carbon and nitrogen cycling with dynamic vegetation) affect the energy/water/carbon cycles in CLM4.0 and how can its treatment be further improved? c) How does groundwater affect other land processes in CLM4.0 and how can its treatment be further improved? and d) How to use the insights gained from these efforts to better understand the uncertainties in the future climate projections of land processes from CCSM4.0?The broader impacts of the proposed work include: a) improving the understanding of energy/water/carbon cycles, improving the treatment of two important processes (i.e., groundwater and dynamic vegetation with carbon and nitrogen cycling), training students, and incorporating research results in teaching; b) upgrading and maintaining a computer cluster for interdisciplinary research; and c) broadly disseminating results through peer-reviewed publications, presentations at conferences and workshops, web page, and lectures to the general public.