Terrain#
easysnowdata.terrain#
Terrain: digital elevation models and topographic indices.
Products#
demCopernicus DEM GLO-30 / GLO-90 (Planetary Computer, Earth Search).
chiliCHILI, the continuous heat-insolation load index (Earth Engine).
import easysnowdata as esd
aoi = (-121.94, 46.72, -121.54, 46.99)
esd.terrain.dem.load(aoi)
esd.terrain.chili.load(aoi)
easysnowdata.terrain.chili#
CHILI — Continuous Heat-Insolation Load Index (§4.5).
import easysnowdata as esd
aoi = (-121.94, 46.72, -121.54, 46.99)
chili = esd.terrain.chili.load(aoi) # native 0-255 values
index = esd.terrain.chili.load(aoi, normalize="index") # the 0-1 index
CHILI is a topographic index of the combined effect of solar radiation and surface temperature computed from ALOS World 3D-30m (Theobald et al. 2015), served at ~90 m between 70°N and 70°S. The Earth Engine asset stores the 0-1 index scaled to 8 bits, so values come back on a 0-255 scale.
Unlike the topography.get_chili shim this loader does not rescale by
default: min-max normalization inside the AOI made values depend on the box
that was requested, so the same pixel changed value with the window
(normalize="minmax" keeps that behaviour for one release).
Load CHILI for aoi from Earth Engine at the asset's native grid. |
easysnowdata.terrain.dem#
Copernicus DEM GLO-30 / GLO-90 (§4.5, companion §B.8).
import easysnowdata as esd
aoi = (-121.94, 46.72, -121.54, 46.99)
items = esd.terrain.dem.search(aoi) # GeoDataFrame
dem = esd.terrain.dem.load(aoi) # Planetary Computer
dem = esd.terrain.dem.load(aoi, source="earth-search") # unsigned AWS COGs
dem = esd.terrain.dem.load(aoi, resolution=90, crs="utm", grid_resolution=90)
Both routes serve the 2021 release of the same global digital surface model; the newer GLO-30 2024_1 release exists only on Earth Engine and CDSE (§B.8).