00590305-fc2c-4b2c-8b22-7f8875b18037 Scenarios Network for Alaska and Arctic Planning uaf-snap-data-tools@alaska.edu 2022-08-18T09:50:38 ISO 19115:2003/19139 1.0 3 WGS 1984 Historical wind data at Alaska airports, 1980-2019 2021-03-17T20:00:00 These wind speed and direction data are the underlying data displayed in the interactive webtool at http://snap.uaf.edu/tools/airport-winds. Original wind speed/direction observations were made by Automated Surface Observing System (ASOS) and the Automated Weather Observing System (AWOS) stations, and we accessed these data via the Iowa Environmental Mesonet (IEM). These observations were hourly in most cases, and we filtered data to routine measurements (nearest to clock hour) where measurements were more frequent than hourly to generate a true hourly dataset, save for periods of missing data. We used data from 166 weather stations located across Alaska, selected from a pool of 185 stations available in the IEM database for 1980-2019. For inclusion in the app and this dataset, a station must have a reasonably complete record, and must have begun measurements before June 6, 2010. We applied a spike-filtering algorithm to detect spurious spikes and dips, and a changepoint detection plus quantile mapping adjustment to statistically account for the possibility of sensors changing location, height, or surroundings such that the long term (month-scale) wind regimes were affected. **Methodology** --- All hourly ASOS/AWOS wind speed and direction data available via the Iowa Environmental Mesonet AK ASOS network were accessed and assessed for completeness (185 stations), and 166 of those stations were determined to be sufficiently complete for climatological analysis. Those data were cleaned to produce regular hourly data, and adjusted via a combination of changepoint analysis and quantile mapping to correct for potential changes in sensor location and height. **Attribute Description** --- ts: timestamp (YYYY-mm-dd HH:MM:SS) ws: wind speed (mph) wd: wind direction (degrees) Station identifiers used for locations is available at: https://www.faa.gov/air_traffic/weather/asos/?state=AK These data were created by SNAP in collaboration with the Western Regional Climate Center for use in the "Historical Winds at Alaska Airports" webtool, https://www.snap.uaf.edu/tools/airport-winds Western Regional Climate Center Scenarios Network for Alaska and Arctic Planning uaf-snap-data-tools@alaska.edu climate wind speed wind direction historical Alaska 1000 eng climatologyMeteorologyAtmosphere 1980-01-01 2019-12-31 -179.15 -131.5722 51.878 71.2826 http://data.snap.uaf.edu/data/Base/Other/historical_winds_Alaska_airports WWW:LINK-1.0-http--link Access data ASOS/AWOS records made available by the Iowa State University Iowa Environmental Mesonet (IEM) at https://mesonet.agron.iastate.edu/request/download.phtml?network=AK_ASOS; Attribute Accuracy: Spike-filtering of hourly ASOS/AWOS data to remove spurious wind speeds. Some non-spurious spikes may have been removed, and it is also likely that not all spurious observations were captured. Wind speed values were adjusted for some stations based on a changepoint detection algorithm applied to the monthly mean time series. This was used to identify potential changes in sensor height or location, or other changes that could cause systematic shifts in observed wind regimes. Quantile mapping was used to adjust wind speeds prior to the changepoint to match the distribution of speeds after the changepoint. Completeness: There are multiple instances of missing data, due to multiple causes. Those causes are: Lack of hourly reporting, particularly in first half of spanning time period Missed/removed hourly observations, present in source data Observations removed by spike-filtering algorithm during processing.