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I want to export the SRTM 30 m elevation data and slope for the country of Indonesia. Here is my script using GEE.

However, on exporting the tiles to my Google Drive, I get this error message- A region must be a GeoJSON Polygon or LinearRing. Got: 'MultiPolygon'.

How do I deal with this i.e. how do I export the elevation (and slope) tiles for Indonesia to my Drive and then download it to my computer?

// Load the SRTM image.
var srtm = ee.Image('USGS/SRTMGL1_003'); //Calling SRTm 30m images

// Apply slope algorithm to an image.
var slope = ee.Terrain.slope(srtm); 

//Scale and Projection
var scale = srtm.projection().nominalScale();
print('SRTM scale in meters', scale); //see Console tab in the right section of screen- 30.92208 m
print('Projection, crs, and crs_transform:', srtm.projection()); //EPSG:4326 is WGS 1984, look at right section of screen 
// in the Console tab

// Load countries border
var countries = ee.FeatureCollection('ft:1tdSwUL7MVpOauSgRzqVTOwdfy17KDbw-1d9omPw');
var justcountry = countries.filterMetadata('Country', 'equals', 'Indonesia'); //change country name here
Map.addLayer(justcountry)

//Displaying slope for country
var elevcountry= srtm.clip (justcountry);
var slopecountry= ee.Terrain.slope(elevcountry);
//var slopecountry_radians= slopecountry.divide(180).multiply(Math.PI) //converting to radians 'divide the slope by 180, multiply the result of that by π
Map.addLayer(slopecountry); //to view

// Export the image, specifying scale and region.
Export.image.toDrive({
  image: elevcountry,
  region: justcountry.geometry().bounds(),
  description: 'elev',
  scale: 30, //pixel size specified 
  maxPixels: 1e12
});

1 Answer 1

6

MultiPolygon exports are not supported. You can calculate the bounding box around your MultiPolygon and use that as export region.

Export.image.toDrive({
  image: elevcountry,
  region: justcountry.geometry().bounds(),
  description: 'elev',
  scale: 30, //pixel size specified 
  maxPixels: 1e12
});

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