text: var dataset = ee.ImageCollection('MODIS/MOD09GA_006_NDSI')
                    .filter(ee.Filter.date('2018-04-01', '2018-06-01'));
  var colorized = dataset.select('NDSI');
  var colorizedVis = {
    palette: ['000088', '0000FF', '8888FF', 'FFFFFF'],
  };
  Map.setCenter(-7.03125, 31.0529339857, 2);
  Map.addLayer(colorized, colorizedVis, 'Colorized');