Arctic Cloud Summer Expedition (ACSE): composite cloud layer data for Icebreaker Oden

This dataset contains derived cloud layer measurements of Icebreaker Oden utilising data from the National Centre for Atmospheric Science's Atmospheric Measurement Facility's (NCAS AMF) Halo Doppler lidar and NOAA cloud radar on board Icebreaker Oden durning Arctic Cloud Summer Expedition (ACSE). ACSE took place in the Arctic during summer 2014. These measurements were used to complement a suite of other observations taken during the cruise. Those of the UK contribution, as well as selected other data, are available within the associated data collection in the Centre for Environmental Data Analysis (CEDA) archives. Other cruise data may be available in the NOAA ACSE and The Bolin Centre for Climate Research SWERUS (SWEdish-Russian-US) holdings - see online resources linked to this record. The data provide altitudes of cloud base and top for the first two cloud layers. Cloud base was established from the laser ceilometer (base of liquid cloud) whist he cloud top was established from the cloud radar data. Where fog was detected, the fog top altitude from the radar data is given. Note: it was possible for the radar to detect a cloud top where the laser ceilometer was not able to detecte a cloud base. These data were prepared for archiving as NetCDF data at the Centre for Environmental Data Analysis (CEDA) by Ian Brooks, University of Leeds. The Arctic Cloud Summer Expedition (ACSE) was a collaboration between the University of Leeds, the University of Stockholm, and NOAA-CIRES. ACSE aimed to study the response of Arctic boundary layer cloud to changes in surface conditions in the Arctic Ocean as a working package of the larger Swedish-Russian-US Investigation of Climate, Cryosphere and Carbon interaction (SWERUS-C3) Expedition in Summer 2014. This expedition was a core component to the overall SWERUS-C3 programme and was supported by the Swedish Polar Research Secretariat. ACSE took place during a 3-month cruise of the Swedish Icebreaker Oden from Tromso, Norway to Barrow, Alaska and back over the summer of 2014. During this cruise ACSE scientists measured surface turbulent exchange, boundary layer structure, and cloud properties. Many of the measurements used remote sensing approaches - radar, lidar, and microwave radiometers - to retrieve vertical profiles of the dynamic and microphysical properties of the lower atmosphere and cloud. The UK participation of ACSE was funded by the Natural Environment Research Council (NERC, grant: NE/K011820/1) and involved instrumentation from the Atmospheric Measurement Facility of the UK's National Centre for Atmospheric Science (NCAS AMF). This dataset collection contains data mainy from the UK contribution with some additional data from other institutes also archived to complement the suite of meteorological measurements.本数据集包含破冰船奥登号（Icebreaker Oden）的衍生云层观测数据，所用数据源自英国国家大气科学中心大气测量设施（National Centre for Atmospheric Science's Atmospheric Measurement Facility, NCAS AMF）的哈洛多普勒激光雷达（Halo Doppler lidar），以及搭载于该船的美国国家海洋和大气管理局（National Oceanic and Atmospheric Administration, NOAA）云雷达，数据采集于2014年夏季北极云层夏季考察（Arctic Cloud Summer Expedition, ACSE）期间。这些观测数据用于补充本次科考航程中的一系列其他观测成果。其中英国贡献的观测数据及部分精选其他数据，可在英国环境数据分析中心（Centre for Environmental Data Analysis, CEDA）存档的关联数据集中获取。其余科考数据可分别从NOAA ACSE数据集以及瑞典博林气候研究中心的瑞典-俄罗斯-美国合作科考（SWEdish-Russian-US, SWERUS）档案中获取，相关信息详见本记录附带的在线资源。本数据集提供前两层云的云底高度与云顶高度数据。其中云底高度通过激光云高仪（laser ceilometer）获取液态云的云底高度，云顶高度则由云雷达数据确定。当检测到雾时，会一并给出雷达观测得到的雾顶高度。需注意：在激光云高仪无法探测到云底的场景下，雷达仍可检测到云顶。本数据集由利兹大学（University of Leeds）的伊恩·布鲁克斯（Ian Brooks）整理，以NetCDF格式准备归档至英国环境数据分析中心（CEDA）。北极云层夏季考察（ACSE）是利兹大学、斯德哥尔摩大学与NOAA-CIRES的合作项目。作为2014年夏季瑞典-俄罗斯-美国气候、冰冻圈与碳相互作用考察（Swedish-Russian-US Investigation of Climate, Cryosphere and Carbon interaction, SWERUS-C3）大型项目的子任务，ACSE旨在研究北极海洋表层条件变化对北极边界层云的影响。本次科考是SWERUS-C3整体计划的核心组成部分，由瑞典极地研究秘书处提供资助。ACSE依托瑞典破冰船奥登号开展了为期3个月的航程，于2014年夏季从挪威特罗姆瑟出发，前往美国阿拉斯加州巴罗后返程。科考期间，ACSE团队开展了多项观测：包括地表湍流交换、边界层结构与云层特性的测量。诸多观测采用遥感手段——包括雷达、激光雷达与微波辐射计——以反演低层大气与云层的动力学及微物理特性垂直剖面。ACSE的英国参与项目由英国自然环境研究理事会（Natural Environment Research Council, NERC，项目编号：NE/K011820/1）资助，所用仪器来自英国国家大气科学中心大气测量设施（NCAS AMF）。本数据集主要收录英国贡献的观测数据，同时补充了部分其他机构提供的相关气象观测数据，一并完成归档。