Climate Change Data Portal
| Evaluating large-eddy simulations of boundary-layer cloud response to climate change using MAGIC observations | |
| 项目编号 | DE-SC0011602 |
| Bretherton, Christopher | |
| 项目主持机构 | University of Washington |
| 开始日期 | 2014-05-01 |
| 结束日期 | 2018-04-30 |
| 英文摘要 | Evaluating large-eddy simulations of boundary-layer cloud response to climate change using MAGIC observations PI: Christopher S. Bretherton, Professor, Department of Atmospheric Sciences, University of Washington Objectives: Low-lying marine boundary layer clouds are a key challenge for global climate projections. The warming predicted by climate models in response to a given change in greenhouse gas concentrations has a 50% uncertainty. The main reason is that as greenhouse gases increase, some climate models predict a large decrease in marine boundary layer clouds, allowing more sunlight to reach the ocean and further warm the planet, while other models do not. The Atmospheric Radiation Measurement (ARM) Program's 2012-2013 MAGIC (Marine ARM GPCI Investigation of Clouds) campaign has deployed a suite of sophisticated instruments for measuring cloud and lower- atmosphere properties on a container ship travelling between California and Hawaii. Marine boundary layer clouds form at the top of turbulent eddies that bring moisture up from the ocean surface. Large-eddy simulations (LES) that model three-dimensional turbulent fluid flow on a very fine computational grid are the most sophisticated small-scale models in use today for studying the processes that form these clouds. This project will comprehensively test how well an LES can predict the variations in cloud cover and thickness sampled during MAGIC, which encompass many of the cloud-controlling factors that are important for climate change. Description: First, measurements will be synthesized for approximately 100 cases of boundary layer clouds observed during MAGIC, spanning a broad range of low-lying cloud types in all seasons and longitudes between California and Hawaii. Each case will include a balloon profile of temperature, moisture and winds and a surrounding period of other continuous ship-based measurements of cloud and aerosol characteristics. The balloon profile, together with aerosol measurements and ancillary measurements, will be used as a starting condition to drive a LES, and the cloud thickness and fractional coverage after 2-6 simulated hours will be compared with the ship cloud and radiation observations. This quality of this comparison will be used to assess whether the LES might reliably predict how low-lying marine cloud properties would respond to expected changes due to greenhouse warming or human-produced aerosols. For example, differences between winter and summer cloud properties might inform how clouds might respond to warming, if changes in other cloud-controlling factors can be accounted for. Impacts: Uncertainties in simulating marine boundary layer clouds in climate models are at the heart of uncertainties of how clouds will respond to climate change, and therefore how sensitive global warming is to human greenhouse gas emissions. This study will test whether LES are reliable enough for accurately predicting the changes in marine boundary layer clouds that are expected to accompany climate change. If so, such LES predictions should be used as a benchmark test for improving the representation of these clouds in climate models. An international model intercomparison project called CGILS (the Cloud Feedbacks Model Intercomparison Project - Global Atmospheric System Study Intercomparison of Large-Eddy Simulations and Single-Column Models) is investigating this strategy, and will directly benefit from the planned MAGIC analyses. |
| 学科分类 | 09 - 环境科学;06 - 生物科学 |
| 资助机构 | US-DOE |
| 项目经费 | 389567 |
| 项目类型 | Grant |
| 国家 | US |
| 语种 | 英语 |
| 文献类型 | 项目 |
| 条目标识符 | http://gcip.llas.ac.cn/handle/2XKMVOVA/70320 |
| 推荐引用方式 GB/T 7714 | Bretherton, Christopher.Evaluating large-eddy simulations of boundary-layer cloud response to climate change using MAGIC observations.2014. |
| 条目包含的文件 | 条目无相关文件。 | |||||
| 个性服务 |
| 推荐该条目 |
| 保存到收藏夹 |
| 导出为Endnote文件 |
| 谷歌学术 |
| 谷歌学术中相似的文章 |
| [Bretherton, Christopher]的文章 |
| 百度学术 |
| 百度学术中相似的文章 |
| [Bretherton, Christopher]的文章 |
| 必应学术 |
| 必应学术中相似的文章 |
| [Bretherton, Christopher]的文章 |
| 相关权益政策 |
| 暂无数据 |
| 收藏/分享 |
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。
