Collaborative Research: Type 1: LOI: L02170303: Arctic Climate Response to Decadal Changes in Radiative Forcing from Aerosols and Ozone

目前的大气环流模式（GCMs）难以重现过去几十年观测到的北极快速变暖和海冰损失。一个可能的因素是，它们不能恰当地代表气溶胶和对流层臭氧的辐射强迫，而这在北极可能特别重要。这个EaSM 1型项目将进一步了解北极气溶胶和臭氧的分布和年代际趋势，包括黑碳（BC）沉积通量和雪和海冰的反照率效应，并将研究1980-2010年期间对北极气候变化的影响。它将在使用GEOS-Chem CTM的大气化学家和使用CCSM4的冰冻圈科学家之间建立一个跨学科的伙伴关系，以更好地描述社区地球系统模型（CESM）中的气溶胶-化学-气候相互作用。该项目将利用国际极地年（IPY）期间的密集观测来测试和改进GEOS-Chem对北极气溶胶、臭氧和BC沉积通量的表示。将对人类活动和火灾不断演变的源进行30年GEOS-Chem模拟（1980-2010），并根据长期记录进行评估。来自GEOS-Chem的气溶胶、臭氧和BC沉积通量将输入CCSM4，以模拟北极30年期间的辐射强迫和气候响应。用CCSM4进行的集合灵敏度模拟将诊断与这些辐射强迫有关的温度、海冰和大气环流的扰动。从该项目中获得的知识将用于评估CESM内北极气溶胶、对流层臭氧和BC沉积通量的模拟。CESM将进行1980-2010年期间气溶胶-化学-气候的完全耦合模拟，以评估气溶胶和臭氧对北极气候的响应，并调查气候反馈。该项目还将为政策分析人员提供有关气溶胶和对流层臭氧在推动北极气候变化中的作用的信息。两名研究生将接受跨学科环境建模培训。

Current general circulation models (GCMs) have difficulty reproducing the rapid Arctic warming and sea ice loss observed over the past decades. One possible factor is that they do not properly represent the radiative forcings from aerosols and tropospheric ozone that could be particularly important in the Arctic. This EaSM Type 1 project will develop an improved understanding of the distributions and decadal trends of aerosols and ozone in the Arctic, including black carbon (BC) deposition fluxes and albedo effects for snow and sea ice, and will study the implications for Arctic climate change over the 1980-2010 period. It will build an interdisciplinary partnership between atmospheric chemists using the GEOS-Chem CTM and cryosphere scientists using CCSM4, to better describe aerosol-chemistry-climate interactions in the Community Earth System Model (CESM). The project will take advantage of intensive observations during the International Polar Year (IPY) to test and improve the GEOS-Chem representation of aerosols, ozone, and BC deposition fluxes in the Arctic. A 30-year GEOS-Chem simulation (1980-2010) with evolving sources from human activity and fires will be conducted and evaluated against long-term records. Aerosols, ozone, and BC deposition fluxes from GEOS-Chem will be input to CCSM4 to simulate Arctic radiative forcing and climate response over the 30-year period. Ensemble sensitivity simulations conducted with CCSM4 will diagnose the perturbations to temperature, sea ice, and atmospheric circulation associated with these radiative forcings. Knowledge gained from this project will be used to evaluate the simulation of Arctic aerosols, tropospheric ozone, and BC deposition fluxes within CESM. Fully coupled aerosol-chemistry-climate simulations of the 1980-2010 period will be conducted in CESM to assess Arctic climate response from aerosols and ozone and to investigate climate feedbacks. This project will also provide policy analysts with information on the role of aerosols and tropospheric ozone in driving Arctic climate change. Two graduate students will be trained in interdisciplinary environmental modeling.