Collaborative Research: NSFGEO-NERC: Integrated Characterization of Energy, Clouds, Atmospheric state, and Precipitation at Summit: Measurements along Lagrangian Transects

这是一个由国家科学基金会地球科学理事会（NSF/GEO）和联合王国国家环境研究理事会（UKRI/NERC）通过NSF/GEO-NERC牵头机构协议共同资助的项目。该协议允许美国/英国提交一份联合提案，并由研究者拥有最大预算比例的机构进行同行评审。一旦成功地共同确定了一个奖项，每个机构的资金比例的预算和调查人员与自己的建议和工作的组成部分。这个研究项目继续一个11年的实地实验称为综合表征的能量，云，大气状态，降水在首脑会议（ICECAPS），并增加测量沿着拉格朗日断面（ICECAPS-MELT）。该项目是一个国际合作项目，自2010年以来一直在格陵兰的Summit站运行地面仪器，对大气进行观测，以促进对云特性、辐射和表面能量以及格陵兰冰盖降水过程的了解。这是一个重要的时间进行这些观察，因为格陵兰岛正在经历变化，由于北极气候的快速变化。目前的项目继续在萨米特站进行观测，并将测量沿着样带扩展到格陵兰另一个重要区域，即渗滤带。在这个区域，融化的水在表面产生，在那里它可以渗透到雪中，然后重新冻结。这就形成了冰层，可以导致额外的融水水平移动，而不是垂直移动。了解这些过程是很重要的，因为格陵兰冰盖的融化是全球海平面的一个重要因素，预计在下一个世纪将对人类产生重大影响。这个新的ICECAPS-MELT项目通过建立一个新的移动的观测站来测量格陵兰冰盖的表面质量和能量收支参数，从而补充了ICECAPS首脑会议观测站。该天文台采用了一种新颖的方法，通过支持需要中等功率和互联网带宽的仪器进行无人值守的自主操作，但与Summit Station的操作非常相似。新的观测站测量地表质量和能量收支参数，包括降水、云的特性、辐射和湍流通量、近地表气象学以及次表层温度和结构。为此，ICECAPS-MELT团队部署了一个降水雷达，一个云激光雷达，一个微波辐射计，一个探地雷达和一个自动表面通量站，在正常情况下消耗约500 W的功率。该项目将导致新的见解如何表面质量和能量预算的参数在这个新的天文台和正在进行的测量之间的空间和时间的共同变化。轨迹分析跟踪空气包裹的变化，因为它们上升的格陵兰冰盖和通过两个观测点。移动的观测站将在连续的夏季部署在干雪区的Summit站和渗透区的DYE-2站。如果这个项目成功，将提议在格陵兰西南部建立一个由这些观测站组成的网络，这将为大气特性和过程如何在空间和时间上与格陵兰冰盖的表面和地下条件相耦合提供新的见解。该奖项反映了NSF的法定使命，并被认为值得通过利用基金会的智力价值和更广泛的影响审查标准。

This is a project that is jointly funded by the National Science Foundation’s Directorate of Geosciences (NSF/GEO) and the National Environment Research Council (UKRI/NERC) of the United Kingdom (UK) via the NSF/GEO-NERC Lead Agency Agreement. This Agreement allows a single joint US/UK proposal to be submitted and peer-reviewed by the Agency whose investigator has the largest proportion of the budget. Upon successful joint determination of an award, each Agency funds the proportion of the budget and the investigators associated with its own proposals and component of the work.This research project continues an 11-year field experiment called the Integrated Characterization of Energy, Clouds, Atmospheric state, and Precipitation at Summit (ICECAPS) and adds measurements along Lagrangian transects (ICECAPS-MELT). The project is an international collaboration that has been operating ground-based instruments at Summit Station in Greenland since 2010, taking observations of the atmosphere to advance understanding of cloud properties, radiation and surface energy, and precipitation processes over the Greenland Ice Sheet. It is an important time to make these observations because Greenland is undergoing changes due to rapid shifts in Arctic climate. The current project continues the observations made at Summit Station and expands measurements along transects to another important region of Greenland called the percolation zone. In this zone, melt water is generated at the surface, where it can percolate down into the snow and then refreeze. This creates ice layers that can cause additional melt water to move horizontally rather than vertically. It is important to understand these processes because melting of the Greenland Ice Sheet is a significant contributor to global sea level, which is predicted to impact humans significantly over the next century.This new ICECAPS-MELT project complements the ICECAPS Summit observatory by building a new mobile observatory for measuring parameters of the surface mass and energy budgets of the Greenland Ice Sheet. This observatory uses a novel approach for unattended, autonomous operation by supporting instruments that require moderate power and internet bandwidth yet are quite like those operated at Summit Station. The new observatory measures surface mass and energy budget parameters, including precipitation, cloud properties, radiative and turbulent fluxes, near-surface meteorology, and subsurface temperatures and structure. To do this, the ICECAPS-MELT team deploys a precipitation radar, a cloud lidar, a microwave radiometer, a ground-penetrating radar, and an automated surface flux station, which consume approximately 500 W of power under normal conditions. The project will lead to new insights into how parameters of the surface mass and energy budgets co-vary in space and time between this new observatory and the ongoing measurements at Summit. Trajectory analyses track the changes in air parcels as they ascend the Greenland Ice Sheet and pass over the two observational sites. The mobile observatory will be deployed in successive summers at Summit Station in the dry-snow zone and at the DYE-2 station in the percolation zone. If this project is successful, a network of these observatories will be proposed for future deployment in southwestern Greenland, which will provide new insights into how atmospheric properties and processes are coupled both spatially and temporally to the ice sheet’s surface and subsurface conditions over Greenland.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.