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orbisgis / geoclimate

Geospatial processing toolbox for environmental and climate studies
GNU Lesser General Public License v3.0
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issue related to impervious indicators ? #774

Closed simogeo closed 1 year ago

simogeo commented 1 year ago

I'm working on Lorient city area, in Britain / France.

And the area which is supposed to be the most impervious appears with very low impervious index.

When adding IMPERVIOUS_FRACTION + ROAD_FRACTION from grid_indicators.json geoclimate result I get on that specific area, an index lower than 0.2. According to people who know the area - it should not ....

The area is on south part :

image

Zoom on concerned area - it seems the Est part should be much darker : image

legend :

image

Clicking one cell, I can see that it is classified as undefined :

image

In red the selected cell : image

Not sure it is a bug or it is due to the data itself. I'm relying on BD TOPO 2.2 analysis.

Thanks for your feedback !

poke @ebocher

j3r3m1 commented 1 year ago

Hi @simogeo Thank you for the feedback. There is a real lack of data in BDTopo nor OSM to simply identify impervious area. However, we might use a trick to consider that by default, all surfaces of commercial or industrial areas (which are identified both in OSM and BDTopo) are impervious. Thus only if vegetation is identified we will replace impervious by vegetation. This will be a future enhancement.