topic Re: RASTER LULC CHANGES (DIFFERENT NUMBER OF TYPES) in ArcGIS Spatial Analyst Questions

RASTER LULC CHANGES (DIFFERENT NUMBER OF TYPES)

MarianaReyes — Mon, 26 Feb 2024 16:49:24 GMT

I need help! my 2007 seven map has only 8 types of land cover but by 2021 it has increase to 9 types. I tried to use the (2021map - 1) + 2007 -1 raster calculator. The output is inaccurate, do you suggest I remove the one type to make it equal? Also I cannot remove that one polygon also. Thank you

Re: RASTER LULC CHANGES (DIFFERENT NUMBER OF TYPES)

DanPatterson — Mon, 26 Feb 2024 16:55:50 GMT

I assume that you are working with rasters of the same extent, cell size, coordinate system and cell alignment

Given that requirement

Combine (Spatial Analyst)—ArcGIS Pro | Documentation

will produce a map showing the unique combinations between rasters (maps)

You can determine which areas stayed the same and which areas changed and what the change was (eg forest to urban etc etc)

Re: RASTER LULC CHANGES (DIFFERENT NUMBER OF TYPES)

MarianaReyes — Mon, 26 Feb 2024 17:03:00 GMT

Yes everything is the same the only think different was that 2007 only had 8 land cover types while 2021 had 9 types.you think its better than the raster calcullator I used? Cause I want to make a matrix with the percentage change, thats why I used the calculator equation above.

Re: RASTER LULC CHANGES (DIFFERENT NUMBER OF TYPES)

DanPatterson — Mon, 26 Feb 2024 17:06:29 GMT

check out Combine, it returns way more information than the raster calculator expression, specifically, no only did it change, but what did it change into

Re: RASTER LULC CHANGES (DIFFERENT NUMBER OF TYPES)

MarianaReyes — Mon, 26 Feb 2024 17:11:02 GMT

if your curious the mangroves turned into grassland hence the additional type. The only thing I have with combined is that I'm not sure about tis matrix form but I wil try to look into it thanks