Arctic Cloud and Aerosol Remote Sensing Research at Arctic Facility for Atmospheric Remote Sensing (AFARS)

北极云通过调节高纬度地区的辐射平衡，对当地和全球的气候和天气产生重大影响，但目前还没有得到很好的了解。由于该地区的气象孤立，缺乏当地气溶胶来源，以及一年中大部分时间遇到的原始空气质量状况，气溶胶输送到该地区可能对云的形成和微物理特性有很大影响。气候变化在极地地区尤其明显，北极云层可能特别容易受到全球变暖的影响，从而提供了额外的气候反馈的可能性。正如即将到来的国际极地年研究工作所认识到的那样，我们必须改进对大气条件的了解。阿拉斯加费尔班克斯大学北极大气遥感设施（AFARS，北纬64.86度和西经147.84度）将开展一项全面的遥感测量计划，以减少我们对北极云和气溶胶特性的不确定性，特别是检查气溶胶对云的间接影响。AFARS拥有三个工作波长为0.532、0.694、1.06和1.574微米的偏振激光雷达，一个0.607微米的氮拉曼通道，一个偏振多普勒w波段（3.2 mm）雷达，以及一套紫外、可见光和红外辐射计。与以前的中纬度研究一样，AFARs的观测将与地球观测系统a系列卫星在立交桥期间的观测相协调。具体目标是使用多个地面和天基遥感器来表征我们地区中高层云的宏观物理和微物理特性，并将其与中纬度对应云进行比较；研究气溶胶在极锋屏障保护下进入正常清洁的北极环境，同时通过多波长退极化、Stokes参数化和拉曼激光雷达相结合的方法改进气溶胶表征；更深入地研究最近的发现，即气溶胶，如运输的亚洲尘埃、火山尘埃和森林火灾烟雾，间接地影响云；并测试卫星方法表征我们观察到的云和气溶胶的能力。这个项目的智力价值在于，它将基于大学的遥感仪器与地球上大部分未被研究的地区的卫星数据相匹配，为根本性的新发现提供了机会。学生和博士后科学家的参与产生了更广泛的影响。新的科学家将在遥感领域接受培训。更广泛地说，这项研究涉及北极气候变化的过程和影响。

Arctic clouds have a significant impact on local and global climate and weather through modulating the radiation balance at high latitudes but are yet not very well understood. Aerosol transport to this region probably has a large influence on cloud formation and microphysical properties because of the region's meteorological isolation, lack of local aerosol sources, and the pristine air quality conditions encountered for much of the year. Climate change promises to be particularly evident in polar regions, and Arctic clouds may be particularly susceptible to the effects of global warming, thus providing the potential for additional climatic feedbacks. Our knowledge of atmospheric conditions must be improved as recognized by the upcoming International Polar Year research effort. A comprehensive remote sensing measurement program from the University of Alaska Fairbanks Arctic Facility for Atmospheric Remote Sensing (AFARS, at 64.86 deg N and 147.84 deg W) will be conducted to lessen our uncertainties about Arctic cloud and aerosol properties, and particularly to examine aerosol indirect effects on clouds. AFARS has three polarization lidars operating at 0.532, 0.694, 1.06 and 1.574 micrometers, a 0.607 micrometer nitrogen Raman channel, a polarimetric Doppler W-band (3.2-mm) radar, and a suite of ultraviolet, visible, and infrared radiometers. As in previous midlatitude studies, AFARs observations will be coordinated with observations by Earth Observing System A-train satellites during overpasses.The specific goals are to use multiple remote sensors, both ground- and space-based, to characterize the macrophysical and microphysical properties of mid- and high-level clouds in our region and to compare them to their midlatitude counterparts; study aerosol intrusions into the normally clean Arctic environment protected by the barrier of Polar Fronts, and at the same time improve aerosol characterization through combined multi-wavelength depolarization, Stokes parameterization, and Raman lidar methods; more intensively study recent findings that aerosols, such as transported Asian dust, volcanic dust, and forest fire smoke, are indirectly affecting clouds; and test the ability of satellite methods to characterize the clouds and aerosols we observe.The intellectual merit of this program is that it matches a unique ensemble of university-based remote sensing instruments with satellite data in a largely unstudied part of the globe, offering the chance for fundamental new discoveries. The broader impacts arise through student and postdoctoral scientist involvement. New scientists will be trained in the remote sensing arena. Even more broadly, the research addresses processes and impacts of climate change in the Arctic.