IPY: Remote Sensing of the Macro and Microphysical Structure of Arctic Clouds During ASCOS

佩尔松0732925大学。国际北极夏季云海研究（ASCOS）将在国际极地年（IPY）期间提供一个机会，以获得北极高纬度浮冰上云的宏观和微观物理特性的测量结果。这些测量将特别独特和有价值，因为它们将与北极边界层结构和过程以及气溶胶浓度和类型的精细测量同时进行。该数据集将成为IPY的遗产。特别是，它们为验证北极云的气候模式参数化提供了关键数据，解决了当前气候模式中确定的一个关键问题。提供的资金用于：1)在破冰船R/V Oden上部署云雷达、微波辐射计和ceilometer，以获得PI将从中得出云的宏观和微观物理特性的测量结果。在2008年7月至9月的国际ASCOS野外项目期间，将在北极附近的全液体、全冰和混合相云中进行测量。宏观物理性质包括云底、云顶、云分数、云持续时间和云反射率。微物理性质包括云相、液态水路径、冰水含量剖面、冰粒有效半径、液态水含量、有效落点半径、垂直速度、湍流耗散率等。2)将这个浮冰过渡季节的这些性质与项目参与者及其他人在SHEBA期间、在阿拉斯加巴罗附近的北冰洋沿岸地点以及在加拿大尤里卡的SEARCH地点得出的类似的浮冰性质进行比较。3)将这些云性质与边界层风和热力学结构的演变以及其他研究人员在ASCOS期间测量的气溶胶的演变和分布在时间和空间上联系起来。这一目标将为当前气候和北极气候变化的关键过程提供见解，并与其他ASCOS参与者的工作高度相关，因此需要重要的国际科学合作。

Persson 0732925Univ. of Colorado/ CIRESThe international Arctic Summer-Clouds Ocean Study (ASCOS) will provide anopportunity during the International Polar Year (IPY) to obtain measurements of macro- and microphysical properties of clouds over the pack ice in the high Arctic. These measurements will be particularly unique and valuable because they will be co-located with fine-scale measurements of the Arctic boundary-layer structure and processes and of aerosol concentrations and types. The data set will be a legacy of IPY. In particular, they provide critical data for validation of climate model parameterizations of Arctic clouds, addressing a key issue identified in current climate models.Funds are provided to:1) Deploy a cloud radar, a microwave radiometer, and a ceilometer onboard the icebreaker R/V Oden to obtain measurements from which the PI will derive cloud macro- and microphysical properties. The measurements will be obtained in Arctic all-liquid, all-ice, and mixed-phase clouds near the North Pole during the international ASCOS field program in July- September, 2008. The macrophysical properties will include cloud base, cloud top, cloud fraction, cloud duration, and cloud reflectivity. The microphysical properties will include cloud phase, liquid water path, and profiles of ice water content, ice particle effective radius, liquid water content, effective drop radius, vertical velocity, and turbulent dissipation rate. 2) Compare these properties during this pack-ice transition season to cloud properties similarly derived by the project participants and others over the pack ice during SHEBA, at Arctic Ocean coastal sites near Barrow, Alaska, and at the SEARCH site in Eureka, Canada.3) Temporally and spatially link these cloud properties to the evolution of the boundary-layer wind and thermodynamic structure and to the evolution and distribution of aerosols measured by other researchers during ASCOS. This objective will provide insights to key processes for the current climate and for Arctic climate change, and is highly linked to work by other ASCOS participants, hence requiring significant international scientific collaboration.