How to export this change map

Question

I am trying to get this change map downloaded for just California, but no matter what I try, it just downloads empty datasets that look like lines. It's always the same size no matter what I change in the export tool, though the curvature of the line changes depending on what I change. The map on Google Earth Engine looks like what I want to download, but it just doesn't download what I see in the GIS. I am new to Google Earth Engine.

Here is the link for the code: https://code.earthengine.google.com/5567b61a8c23371162ce15dcd9efab18

And here is a copy-paste of the code:

///////////////////////////////////////////////////////////
// I just want to download this change map for California
///////////////////////////////////////////////////////////

// Fetch the states to crop with
var states = ee.FeatureCollection("TIGER/2016/States");

// Just get Cali
var CA = states.filter(ee.Filter.eq('NAME', 'California'));

// Fetch that CCDC map, cropped to Cali. Mosaic the tiles.
var ccdc = ee.ImageCollection("GOOGLE/GLOBAL_CCDC/V1")
      .filterBounds(CA)
      .map(function(image){return image.clip(CA)})
      .mosaic();
      

      
      
//print(ccdc);

//Map.addLayer(ccdc);

// I found these tools at
//   https://gee-ccdc-tools.readthedocs.io/en/latest/
// That website seems like a great resource for this CCDC-type data
var utils = require('users/parevalo_bu/gee-ccdc-tools:ccdcUtilities/api');

// Spectral band names I want to work with (for now).
// I really just would like to start with Enhanced Vegetation Index (EVI)
// But I don't know how to make a band composite
var BANDS = ['NIR', 'RED', 'BLUE'];

// Max number of segments
var n_segments = 10;

// Obtain CCDC results in 'regular' ee.Image format.
// Rather than having bands with variable dimension arrays (based on the # of disturbances)
// it stacks the raster into 'n_segments' layers for every pixel.
// I think this is required before one can download.
var ccdImage = utils.CCDC.buildCcdImage(ccdc, n_segments, BANDS);

//print(ccdImage);

Map.addLayer(ccdImage.select('S1_NIR_coef_COS2'));

var proj = ccdImage.select('S1_NIR_MAG').projection().getInfo();
var geom = ccdImage.geometry().getInfo();


// Okay, below is how I was trying to download. It runs, but just gives me
// this 30 kb (or something) piece of nothing.

// Export the image, specifying the CRS, transform, and region.
// Export.image.toDrive({
//   image: ccdImage,
//   description: 'ccdc_CA',
//   crs: proj.crs,
//   crsTransform: proj.transform,
//   region: geom
// });

Answer 1

The problem is you're using a projection in the Export without knowing what it is. The image you're exporting is being produced from a mosaic of multiple tiles; it has no projection (which means it reports EPSG:4326 at 1 degree/pixel when you ask for the projection).

Specify a real projection and scale to make sure you know what it is. You can inspect one of the CCDC tiles covering your region to try to gt the "original" projection, but if your ROI is large enough you might span multiple tiles (and then you're going to have to pick one).