[{"title":"Ceilometer backscatter, cloud base height and cloud fraction data from the Arctic Ocean 2016 expedition","summary":"Measurements of cloud base height, cloud fraction and backscatter profiles from the ceilometer operating on icebreaker Oden\u2019s 7th deck during the Arctic Ocean 2016 expedition to the High Arctic.","citations":"","comments":"The height to the lowest cloud base, and up to two additional cloud bases when the lowest cloud layer does not cover the whole sky, was measured by a Vaisala CL51 ceilometer, located above Oden\u2019s bridge on the 7th deck. The ceilometer, owned by the Finnish Meteorological Institute (FMI), was deployed as part of the Stockholm University weather station. \r\n\r\n\r\nThe system uses a proprietary Sky Condition algorithm to determine cloud fraction at up to five levels, converting single-point time-series measurements to time-averaged area coverage. The system additionally recorded the backscatter profile, and hence serves as a so-called poor-man\u2019s LiDAR. When the attenuation of the laser beam reaches a threshold, like in a dense fog, it switches to reporting vertical visibility, rather than cloud-base height.\r\n\r\n\r\nData from the ceilometer are combined into a cruise-length file. The data are time-averaged to both 1-minute and 30-minute intervals, to correspond with the micrometeorological averaging periods used for the mast sensors.\r\n\r\n\r\nCoordinates (lat, lon) for the observations are not included in this dataset, but they are the same as in the Weather data from MISU weather station during the Arctic Ocean 2016 expedition.\r\n\r\n\r\nMore information about the Canadian-Swedish Arctic Ocean 2016 expedition is available from the Swedish Polar Research Secretariat.","category":"Atmosphere","subcategory":"Clouds","keywords":"Cloud-base height; Cloud fraction; Backscatter profile; Meteorology; Arctic boundary layer; Arctic clouds; High Arctic; Arctic Ocean 2016; AO2016; AO16; ACAS; Oden","scientist":"John Prytherch, Michael Tjernstr\u00f6m, Ian Brooks","firstname":"John","lastname":"Prytherch","address":"Department of Meteorology (MISU), Stockholm University","postalcode":"SE-106 91","city":"Stockholm","province":"","country":"Sweden","parameters":"Earth science > Atmosphere","location":"Ocean > Arctic Ocean","progress":"Completed","language":"English","project":"Arctic Ocean 2016 expedition. These data were processed as part of the Arctic Climate Across Scales (ACAS) project, funded by the Knut and Alice Wallenberg Foundation. Project PI Michael Tjernstr\u00f6m (MISU).","publisher":"Bolin Centre Database","version":"1.0","constrains":"None","access":"Free"}]