A Prototype Network for Measuring Arctic Winter Precipitation and Snow Cover (SnowNet 1 and 2)

The grant, a collaboration between 0632131 (Sturm, CRREL, LEAD), 0632160 (Kane, UAF) and 0632133/1023562 (Liston, CSU; Hiemstra, CRREL). The chief goal is working to develop better instruments and ways of measuring snow in the Arctic, and analyzing the resultant data. At sites at Barrow, Imnavait Creek, Fox, and Nome Creek Alaska, and in Inuvik, Canada the team has installed meteorological and snow measuring instrumentation including solid-state snow pillows, heated plate precipitation sensors, snow fences (to capture the wind-blown flux), and normal and eddy correlation meteorological towers for monitoring snowfall and snow on the ground. In addition to these autonomous instruments, the team periodically runs intense field campaigns during which a variety snow surveys are conducted, including surveys of snow cover depth, snow water equivalent, density, stratigraphy and other properties. These ground-based surveys are being augmented using aerial photography and ground- and airborne LiDAR. Part of the project is also focused on developing new types of sensors and techniques, including the development of small, low-cost sonic sounders for depth, rotating sonic sounders for better averages of depth, and airborne and ground-based light detection and ranging (LiDAR) for extensive snow depth and surface topography. The combined suite of instrument development and measurement protocols is designed to allow closure of the winter water balance and lead to better ways of monitoring Arctic snow for climate. Within the U.S., this improvement in monitoring would directly benefit the National Resource Conservation Service (NRCS), one of the prime agencies charged with monitoring precipitation and snow cover, as well as the U.S. Weather Service. In addition, the project is contributing to the education of several graduate students, and has had positive impact on the general public through the publication of an English-Inupiat glossary as well as two other books and several papers on the Arctic. The project data on ACADIS have been separated into time series data as reported from the autonomous instruments like weather stations and webcams, and intermittent data from field campaigns collected by humans. These latter appear by campaign date. Because the data come from five (5) different Arctic locations, and at each location have been obtained from a spatial extent that ranges from a few to hundreds of kilometers, a data user is advised to contact the Project Leader (Dr. M. Sturm, [e-mail]) for specific metadata information. A file called aSnowNetReadme.pdf provides an overview of the concept of the project as well as details about the observatory sites.本资助项目由0632131（Sturm，CRREL，LEAD）、0632160（Kane，UAF）以及0632133/1023562（Liston，CSU；Hiemstra，CRREL）三方合作开展。项目核心目标为研发更先进的北极积雪测量仪器与方法，并对所得观测数据进行分析。研究团队已在阿拉斯加的巴罗（Barrow）、伊纳维特溪（Imnavait Creek）、福克斯（Fox）、诺姆溪（Nome Creek）以及加拿大因纽维克（Inuvik）等站点安装了气象与积雪测量仪器，包括固态积雪压力垫、加热式平板降水传感器、积雪栅栏（用于捕获风输雪通量）以及常规与涡动相关气象塔，用于监测降雪与地表积雪状况。除上述自主运行的仪器外，团队还定期开展高强度野外作业，实施各类积雪调查，涵盖积雪深度、雪水当量、密度、层理结构及其他积雪特性的测量。此类地面调查工作辅以航空摄影以及地面、机载激光雷达（light detection and ranging, LiDAR）。本项目同时聚焦新型传感器与技术的研发，包括用于积雪深度测量的小型低成本声波测深仪、用于获取更具代表性平均深度值的旋转式声波测深仪，以及用于大范围积雪深度与地表地形测绘的地面、机载激光雷达（LiDAR）。整套仪器研发与测量规程旨在实现冬季水量平衡闭合，并优化北极积雪的气候监测手段。在美国境内，该监测能力的提升将直接惠及美国国家自然资源保护局（National Resource Conservation Service, NRCS）——负责降水与积雪覆盖监测的核心机构之一，以及美国国家气象局（U.S. Weather Service）。此外，本项目助力多名研究生的培养，并通过发布英-伊努皮克语术语表、另外两部专著及多篇北极相关学术论文，对公众科普产生了积极影响。本项目在ACADIS平台上的数据分为两类：一类为自动气象站、网络摄像头等自主仪器产出的时序数据，另一类为人工开展野外作业获取的间歇式测量数据，后者按作业日期进行分类。由于数据来自5个北极观测站点，且各站点的空间覆盖范围从数公里至数百公里不等，建议数据使用者联系项目负责人（M. Sturm博士，[e-mail]）获取具体元数据信息。另有一份名为"aSnowNetReadme.pdf"的文件，概述了项目理念并详细介绍了各观测站点的情况。