search

orbisgis / geoclimate

Geospatial processing toolbox for environmental and climate studies
GNU Lesser General Public License v3.0
59 stars 15 forks source link

Roads/tracks in the countryside #887

Closed wurtzj closed 8 months ago

wurtzj commented 9 months ago

Hi everyone,

We are experiencing some strange road fractions in Essone departement (while it seems Ok on Eure et Loire). Are "track" roads are taking into account in the total road fraction ? If yes, maybe it would be better to include them in the bare soil fraction ?

Thanks,

Jean

ebocher commented 9 months ago

Is it possible to share a bbox area or a link from https://www.openstreetmap.org/ ? Cheers

j3r3m1 commented 8 months ago

@wurtzj tracks are taken only if they have a surface that belong to one of the following: ['unpaved', 'asphalt', 'paved', 'cobblestone', 'metal', 'concrete', 'compacted'] (cf. https://github.com/orbisgis/geoclimate/blob/870015f18eb224210180e9c8d5f3a8edad473021/osm/src/main/groovy/org/orbisgis/geoclimate/osm/InputDataFormatting.groovy#L330C63-L330C143).

Many tracks do not have a surface type. However they might have a tracktype and in this case we derive the surface from the following rules: https://github.com/orbisgis/geoclimate/blob/870015f18eb224210180e9c8d5f3a8edad473021/osm/src/main/groovy/org/orbisgis/geoclimate/osm/InputDataFormatting.groovy#L294

As you can see, a track having a grade4 or grade5 as tracktype or having no surface type will not be conserved for any analysis.

This is why it might be interesting if you can give us the zone you meet strange results since it might be explainable by the tracktype or the surface missing.

I had a try for the following bbox: http://bboxfinder.com/#48.236565,1.913681,48.300782,2.032814 It is difficult to say anything about such small zone but visually it seems that the tracks are not taken into account both in the West or in the East of the train line (which is near the department boundary): image image

j3r3m1 commented 8 months ago

I have investigated at larger scale the differences nearby the boundary between the 2 departments (let's say left and right) and I cannot see much difference when averaging results at grid scale.

@wurtzj, is it nearby this zone that you have observed problems ? image

wurtzj commented 8 months ago

Hi @j3r3m1

Thanks for having a look. It seems that either this is not an issue, or this issue comes from post-processing. But strangefully as looking more closely to the map it seems there are indeed more roads on the left handside department. Maybe more money for roads there ?...