Collaborative Research: Evaluation of a Coupled Meteorology-Chemistry Model Against Long-term Measurements of Elemental Carbon and Sulfate for Regional Climate Applications

本研究项目的主要目标是：(1)确定两个不同年份夏季和冬季月份在纽约州梅维尔和纽约州怀特菲斯山下风约530公里处收集的存档过滤器中的元素碳浓度{EC}；(2)利用这些数据评估由PI Shankar开发的关于颗粒物、臭氧及其前体的化学和输送及其对大气动力学的辐射反馈的耦合气象-化学模型。该项目的动机是这样一个事实，即颗粒状黑碳（BC）在测量中被视为与EC相当，是一种强烈的太阳辐射吸收剂，并且被认为占全球变暖估计的15-30%，仅次于温室气体；然而，这种对气候的影响程度是高度不确定的。气溶胶BC的停留时间约为一周，因此在被清除之前可以移动数千公里；因此，其浓度取决于与排放源的距离。对美国附近和偏远BC源的辐射影响的可靠估计，关键取决于获得具有区域代表性的测量结果。pi将测定1998年和2002年夏季每6小时收集一次的过滤器{EC}，冬季每48小时收集一次，Mayville每年每24小时收集一次。此外，已经确定了{SO4}，并可对这两个地点的臭氧进行持续时间的实时测量。先前的研究表明，这两个地点的EC和SO4测量值具有区域代表性，并且与已知的迎风气团输入高度相关。这些测量结果将用于评估METCHEM（气象化学），该模型将第五代宾夕法尼亚州立大学/国家大气科学中心（NCAR）中尺度模型（MM5）的中尺度气象学与多尺度空气质量模拟平台（MAQSIP）模拟的颗粒和气相物质化学和输送算法动态耦合。最终目的是模拟它们对大气动力学的辐射反馈。在观测站点上嵌套的大陆到区域到地方尺度的模拟将允许pi检查远程传输和网格细化对模式预测的影响。将使用输入数据中的三种不同的排放清单来检查模型对排放增长和控制的敏感性，以及对诸如野火和风吹尘埃等来源表示的连续改进的敏感性。该项目将建立在目前nsf资助的测量和建模项目的基础上，由两个pi执行。它将有助于评估用于预测下风负担和EC和化石燃料消耗的其他排放对气候影响的模型。经评估的模型及其生成的数据集将为科学界阐明这些排放对气候的影响提供有价值的工具。该项目的结果将成为纽约州立大学奥尔巴尼分校一名学生博士论文的基础，北卡罗莱纳大学环境项目入门级建模师的参与也将促进新研究人员的培训。最后，政策制定者和共同政策制定者的积极作用将扩大在性别和地域方面代表性不足的群体在这一领域的参与。

The primary objectives of this research project are to: (1) determine the elemental carbon concentrations, {EC}, in archived filters collected at Mayville, NY, and ~530 km downwind at Whiteface Mt, NY, for a summer and a winter month in two different years; and (2) to use these data to evaluate a coupled meteorology-chemistry model developed by PI Shankar for the chemistry and transport of particulates, ozone and their precursors, and their radiative feedbacks to the atmospheric dynamics. The project is motivated by the fact that particulate black carbon (BC), which is treated equivalent to EC in the measurements, is a strong absorber of solar radiation, and thought to account for ~15-30% of global warming estimates, next only to greenhouse gases; however, the magnitude of this forcing on climate is highly uncertain. Aerosol BC has a residence time of about a week so it can travel thousands of kilometers before removal; thus its concentrations are dependent on the distance from emission sources. Reliable estimation of the radiative impacts in the U.S. from nearby and remote sources of BC depends critically on obtaining regionally representative measurements. The PIs will determine the {EC} in filters collected every 6 h during summer and every 48 h during the winter of 1998 and 2002 at Whiteface Mt, and every 24 h at Mayville for the same years. In addition, {SO4} have already been determined, and real-time measurements of ozone are available for both the sites for the duration. Prior studies have shown EC and SO4 measurements from these two sites to be regionally representative and highly correlated with known import of upwind airmasses. The measurements will be used to evaluate METCHEM (METeteorology-CHEMistry), a model that dynamically couples the mesoscale meteorology of the Fifth Generation Penn State/National center for Atmospheric Sciences (NCAR) Mesoscale Model (MM5) with algorithms for particulates and gas-phase species chemistry and transport simulated by the Multiscale Air Quality Simulation Platform (MAQSIP). The ultimate purpose is to simulate their radiative feedbacks to the atmospheric dynamics. Nested continental- to-regional- to-local-scale simulations over the observational sites will allow the PIs to examine the effects of long-range transport and grid refinement on the model predictions. The model sensitivity to emissions growth and control, and to successive improvements in the representation of sources such as wild fires and wind-blown dust will be examined using three different emission inventories in the input data. The project will build upon, and augment current NSF-funded measurement and modeling projects being performed by both PIs. It will help evaluate a model used to predict the downwind burden and climate impacts of EC and other emissions from fossil fuel consumption. The evaluated model and the datasets it generates will provide tools of value to the scientific community in illuminating the impacts of these emissions on climate. The results from this project will be the basis for the Ph.D. dissertation of a student at SUNY, Albany, and participation by entry-level modelers at the University of North Carolina-Carolina Environmental Program will also foster training of new researchers. Finally, the active roles of the PIs and Co-Is will broaden participation by groups underrepresented in gender and geography in this field.