Atmospheric Trace Constituents and Global Climate

大气微量成分和全球气候

• 批准号: 9415336
• 负责人: Wei-Chyung Wang
• 金额: $ 28.44万
• 依托单位: SUNY at Albany
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-12-01 至 1999-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9415336&HistoricalAwards=false
• 关键词: Atmospheric; Trace; Constituents; Global; Climate

Abstract ATM-9415336 Wang, Wei-Chyung SUNY Albany Title: Atmospheric Trace Constituents and Global Climate Atmospheric ozone absorbs incoming solar radiation, in particular, the UV-B radiation and acts as s greenhouse gas by absorbing outgoing longwave radiation. Recent studies suggest that the observed ozone changes in the stratosphere and troposphere can substantially perturb the radiative forcing with important climate implications. However, large uncertainties exist, mainly related to radiative transfer schemes and vertical distributions of ozone and temperature. In addition, ozone is a secondary constituent formed by chemical reactions in the atmosphere involving several precursors (NOx, hydrocarbons and CO). The concentrations of these precursors depend on the oxidation process in the atmosphere, which varies strongly with time and space (and thus the climate state) and depends, in addition to the precursors, on the hydrogen radicals like OH and HO2. There fore, it is necessary to have a self-consistent chemistry-radiative-dynamical model to stimulate the observed ozone changes and account for the feedbacks in computing the radiative forcing. Concerns have also been raised in recent years about the climatic efffect due to increasing tropospheric sulfate aerosols of anthropogenic origin. The aerosols are expected to cool the surface by directly backscattering the solar radiation and directly enhancing the cloud albedo due to increased aerosol cloud condensation nuclei. However, large uncertainties exist in the calculated radiative forcing, in particular the enhancement of the cloud albedo, and its climatic effect. This project will continue modeling and observational studies of "global climate and atmospheric trace constituents" with focus on atmospheric ozone and sulfate aerosols. The PI will use an improved radiation model to address several issues related to the radiative forcing calculations associated with observed ozone changes. His ma in effort is to use the NCAR/GENESIS (General ENvironmental and Ecological Simulation of Interactive Systems) global model to study the direct climatic effects due to observed ozone changes and increased sulfate aerosols. For the indirect climatic effects, two exploratory tasks are initiated: the development of a coupled climate-chemistry model through continued collaboration with Prof. Ivar Isaksen at the University Oslo; and the study of increased cloud albedo associated with enhanced number density of sulfate aerosols and its parameterization for use in GENESIS through collaboration with Dr. Joyce Penner at the Lawrence Livermore National Laboratory. This research is important because it addresses questions of primary importance to global change research.

摘要ATM-9415336 Wang，Wei-Chyung纽约州立大学奥尔巴尼题目：大气痕量成分和全球气候 大气臭氧吸收入射的太阳辐射，特别是UV-B辐射，并通过吸收向外的长波辐射而成为温室气体。 最近的研究表明，观测到的平流层和对流层臭氧变化可对辐射强迫产生重大干扰，并对气候产生重要影响。 然而，存在很大的不确定性，主要涉及辐射传输方案和臭氧和温度的垂直分布。 此外，臭氧是通过大气中涉及几种前体（NOx、碳氢化合物和CO）的化学反应形成的次要成分。 这些前体的浓度取决于大气中的氧化过程，该过程随时间和空间（以及气候状态）而强烈变化，并且除了前体之外，还取决于氢自由基，如OH和HO 2。 因此，有必要有一个自洽的化学辐射动力学模型来模拟观测到的臭氧变化，并在计算辐射强迫时考虑反馈。 近年来，由于人为来源的对流层硫酸盐气溶胶的增加而引起的气候效应也引起了人们的关注。 预计气溶胶将通过直接反向散射太阳辐射并由于气溶胶云凝结核的增加而直接增强云反照率来冷却表面。 然而，在计算的辐射强迫，特别是云的增强，其气候效应存在很大的不确定性。 该项目将继续进行“全球气候和大气痕量成分”的模拟和观测研究，重点是大气臭氧和硫酸盐气溶胶。 PI将使用改进的辐射模型来解决与观测到的臭氧变化相关的辐射强迫计算相关的几个问题。 他的主要工作是使用NCAR/GENESIS（交互系统的一般环境和生态模拟）全球模式来研究由于观测到的臭氧变化和硫酸盐气溶胶增加而造成的直接气候影响。 对于间接的气候影响，两个探索性的任务开始：通过继续与奥斯陆大学的Ivar Isaksen教授合作，开发一个耦合的气候-化学模式;以及通过与劳伦斯利弗莫尔国家实验室的Joyce Penner博士合作，研究与硫酸盐气溶胶数量密度增加有关的云的蒸发量增加及其参数化，以用于GENESIS。 这项研究很重要，因为它解决了全球变化研究的首要问题。