1c1de476-cc9d-4c7b-b8ab-25e8f68a317e Scenarios Network for Alaska and Arctic Planning uaf-snap-data-tools@alaska.edu 2023-10-19T14:58:01 ISO 19115:2003/19139 1.0 3 EPSG:3338 Historical and projected climate indicators for Alaska at 12km 2023-10-19 This dataset contains climate "indicators" (also referred to as climate indices or metrics) computed over one historical period (1980-2009) using the NCAR Daymet dataset, and two future periods (2040-2069, 2070-2099) using two statistically downscaled global climate model projections, each run under two plausible greenhouse gas futures (RCP 4.5 and 8.5). The indicators within this dataset include: hd: “Hot day” threshold -- the highest observed daily maximum 2 m air temperature such that there are 5 other observations equal to or greater than this value. cd: “Cold day” threshold -- the lowest observed daily minimum 2 m air temperature such that there are 5 other observations equal to or less than this value. rx1day: Maximum 1-day precipitation su: "Summer Days" –- Annual number of days with maximum 2 m air temperature above 25 C dw: "Deep Winter days" –- Annual number of days with minimum 2 m air temperature below -30 C wsdi: Warm Spell Duration Index -- Annual count of occurrences of at least 5 consecutive days with daily mean 2 m air temperature above 90th percentile of historical values for the date cdsi: Cold Spell Duration Index -- Same as WDSI, but for daily mean 2 m air temperature below 10th percentile rx5day: Maximum 5-day precipitation r10mm: Number of days with precipitation > 10 mm cwd: Consecutive wet days –- number of the most consecutive days with precipitation > 1 mm cdd: Consecutive dry days –- number of the most consecutive days with precipitation < 1 mm Kyle Redilla Scenarios Network for Alaska and Arctic Planning uaf-snap-data-tools@alaska.edu https://catalog.snap.uaf.edu/geonetwork/srv/api/records/1c1de476-cc9d-4c7b-b8ab-25e8f68a317e/attachments/ncar12km_indicators_preview.png indicators temperature precipitation indices modeled historical projected https://creativecommons.org/licenses/by/4.0/ 12 eng climatologyMeteorologyAtmosphere 1980-01-01 2099-12-31 -173.00 -131.00 54.00 71.40 This data is derived from the daily climate estimates (historical) and projections (future) through two steps. First, indicators are computed at a yearly scale from the daily data values using the xclim library (https://xclim.readthedocs.io/en/stable/), giving values for each indicator for each year in the range of 1980-2099. Second, those yearly indicator values are summarized by minimum, mean, and maximum operations over one historical era (1980-2009) and two future eras (2040-2069, 2070-2099). This dataset contains data from two global climate models (GCMs), NCAR-CCSM$ and MRI-CGCM3, and one historical estimated product, Daymet. Data files are GeoTIFFs (.tif) and are named as follows: ncar12km_indicators_<indicator name>_<summary era>_<model>_<scenario>_<summary statistic>.tif Here are the following indicators available in this dataset: hd: “Hot day” threshold -- the highest observed daily maximum 2 m air temperature such that there are 5 other observations equal to or greater than this value. cd: “Cold day” threshold -- the lowest observed daily minimum 2 m air temperature such that there are 5 other observations equal to or less than this value. rx1day: Maximum 1-day precipitation su: "Summer Days" –- Annual number of days with maximum 2 m air temperature above 25 C dw: "Deep Winter days" –- Annual number of days with minimum 2 m air temperature below -30 C wsdi: Warm Spell Duration Index -- Annual count of occurrences of at least 5 consecutive days with daily mean 2 m air temperature above 90th percentile of historical values for the date cdsi: Cold Spell Duration Index -- Same as WDSI, but for daily mean 2 m air temperature below 10th percentile rx5day: Maximum 5-day precipitation r10mm: Number of days with precipitation > 10 mm cwd: Consecutive wet days –- number of the most consecutive days with precipitation > 1 mm cdd: Consecutive dry days –- number of the most consecutive days with precipitation < 1 mm The source downscaled climate dataset used here is the "21st Century Hydrologic Projections for Alaska and Hawaii" developed by the UCAR/NCAR Research Applications Laboratory (https://doi.org/10.5065/c3kn-2y77; associated paper can be found at https://doi.org/10.1016/j.cliser.2022.100312). The code used for developing this dataset can be found on GitHub at https://github.com/ua-snap/ardac-curation/tree/4b39c69df1841701e6f5b9d6e06815b4167fc8fa/ncar12km_indicators. GeoTIFF 1.0 http://data.snap.uaf.edu/data/Base/AK_12km/indicators WWW:LINK-1.0-http--link Data download URL to web-accessible folder containing downloads for this data set https://doi.org/10.5065/c3kn-2y77 WWW:LINK-1.0-http--link Parent dataset Link to the dataset used to derive this dataset.