High-resolution microclimatic grids for the Bohemian Forest Ecosystem

Here, we provide spatially continuous, high-resolution (5 m) microclimate grids covering all 923 km² of the Bohemian Forest Ecosystem (BFE), i.e. the complete area of the Šumava (Czech Republic) and Bavarian Forest (Germany) National Parks.

To derive these grids, we have established a dense network of 288 microclimatic stations that continuously measured air, near-surface, and soil temperature every 15 minutes from 12th October 2019 to 11th October 2020. We combined the measured microclimate temperature with LiDAR derived land surface topography and forest structure through boosted spatial generalized additive models (GAMs).

We validated the resulting microclimatic grids with an independent network of forest weather stations and compared these microclimatic grids with the SoilTemp (soil temperature), ForestTemp (near-ground forest understorey temperature), and downscaled ERA5-Land (air temperature). The developed BFE microclimatic grids were closer to independently measured temperatures than any other alternative and captured high microclimatic variability controlled jointly by land surface topography and forest structure. 

Our microclimatic grids represent accurate, high-resolution spatial variation of mean annual soil temperature, mean, maximum and minimum air temperature at two heights, and growing degree days at 200 cm. 

The dataset contains 8 microclimatic grids (GeoTIFF format, coordinate system EPSG 31468, resolution 5 m).

Extent: 4587063, 5399139: 4646023, 5451289

The name of the file is “name.tif”, where name represents the abbreviation of the microclimatic variable (see names below).

The values are in °C (°C d for GDD), the data can be readily imported into standard geographical information system software (e.g., QGIS) or accessed in a statistical software (e.g., R). The datasets do not include colour schemes.

Measured variable (depth/height)  
 - Microclimatic variable    Abbreviation  (Units)

Soil temperature (-8 cm)             
 - Mean temperature = mean temperature          T.soil_8_cm.mean    (°C)
            
Near-ground air temperature (15 cm)    
    - Mean temperature = mean temperature       T.air_15_cm.mean     (°C)
    - Maximum temperature = 95^th percentile of daily maximum temperatures     T.air_15_cm.max.95p    (°C)
    - Minimum temperature = 5^th percentile of daily minimum temperatures        T.air_15_cm.min.5p    (°C)
            
Air temperature (200 cm)    

    - Mean temperature = mean temperature    T.air_200_cm.mean    (°C)
    - Maximum temperature = 95^th percentile of daily maximum temperatures     T.air_200_cm.max.95p    (°C)
    - Minimum temperature = 5^th percentile of daily minimum temperatures     T.air_200_cm.min.5p    (°C)
    - Growing degree days = sum of degree days above base temperature (base 5°C)      T.air_200_cm.GDD5    (°C d)

BFE_script_and_data.zip contains

     - Microclimatic variables, topography and forest structure variables for all stations used for modelling (BFE_data.RData).
     - Script BFE_microclimate_maps_model_script.R used for statistical modelling and prediction.
     - microclimate2predict.csv - list of microclimate variables for prediction used in the script.

The data used for prediction cannot be made publically available.  
The LIDAR data can be obtained from Administration of Bavarian Forest National Park and Šumava National Park Administration. The LIDAR-derived topography and forest structure rasters can be obtained upon request from the authors.

Detailed description will be available in a manuscript.

Version 2 insludes improved rasters, the GeoTIFFs include aplha channel for transparency of pixels with NA and full script used for processing.