40-year monthly mean AVHRR GAC Land Surface Temperature data for the Pan-Arctic region (Pan-Arctic AVHRR LST)

This data collection contains 40 years of monthly mean daytime AVHRR  Global Area Coverage (GAC)  land surface temperature (LST) data. This dataset covers the 1981-2020 perdiod and covers the whole globe above 50° latitude. The spatial extent of the dataset is the following : (-180°, 50°N) ; (180°, 90°N)

Dataset description:

The LST monthly mean composites are computed from daily daytime LST files, that were generated from the EUMETSAT AVHRR PyGAC FDR (https://navigator.eumetsat.int/product/EO:EUM:DAT:0862) as described in Dupuis et al. (2024). These daily LST files contain only cloud-free pixels and pixels with sufficient quality regarding satellite zenith angle and error margin from the radiative transfer modelling. The probabilistic cloud mask from the CLARA-A3 (https://navigator.eumetsat.int/product/EO:EUM:DAT:0874) dataset has been used. The LST monthly means do not contain any water masks, as potential users might have different requirements regarding water masks. The dataset has been validated against in situ data from the SURFRAD (https://gml.noaa.gov/grad/surfrad/overview.html), ARM (https://arm.gov/capabilities/observatories/nsa) and KIT (https://www.imk-asf.kit.edu/english/skl_stations.php) networks.

Data & File Overview:

Short description: AVHRR GAC LST daytime monthly mean composites: daily land surface temperature data are averaged to monthly composites for every afternoon and mid-day satellite (10 different satellites).

• File List: This dataset contains monthly daytime land surface temperature (LST) data for the AVHRRs onboard NOAA and MetOp satellites. 
• Filename: Pan_Arctic_LST_avhrr_XXXXX_YYYYMM_DAY__***.nc, where XXXXX represents the satellite identifier, YYYYMM the monthly timestamp (YYYY=year, MM=month) and *** the timestamp of the file generation.
• Relationship between files: Each file covers a one-month period and is recorded by a different satellite.

Satellite identifiers:
AVN07 : NOAA 7
AVN09 : NOAA 9
AVN11 : NOAA 11
AVN14 : NOAA 14
AVN16 : NOAA 16
AVN18 : NOAA 18
AVN19 : NOAA 19
AVMEA : MetOp-A
AVMEB : MetOp-B
AVMEC : MetOp-C

Data specific information:

The LST files are available as a gridded product in the WGS84 coordinate reference system and are distributed as NetCDF files. The dataset covers the pan-Arctic region (-180°, 90°, 180°, 50°) at a spatial resolution of 0.05°x0.05° pixel size.
Each *.nc file contains one variable (LST) with three dimensions (time, lat, lon) and five coordinates (time, lat, lon, band and spatial_ref).

- spatial_ref (): stores the spatial information, such as the coordinate reference system (CRS) and WKT string.
- time (time): stores the timestamp, here the month and the year of the monthly mean. The timestamp is the same for all pixels belonging to the same composite.
- lat (lat): stores the latitude of each pixel
- lon (lon): stores the longitude of each pixel
- band (): empty inherited layer 

Credit:

To use this data please cite this dataset and the respective journal publication:

Dupuis, S., Göttsche, F.-M., and Wunderle, S.: Temporal stability of a new 40-year daily AVHRR Land Surface Temperature dataset for the Pan-Arctic region, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2024-857, 2024. 

Information about funding sources that supported the collection of the data:
Dr. Alfred Bretscher Fund (University of Bern)