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Trying to modify a code in Google Earth Engine I found in the internet which I need for performing time series analysis. I need Landsat images from 1984-2022, that’s why I merged two Image Collection (L5 and L8). But I am getting an error: ImageCollection (Error) Error in map(ID=28): Image.select: Pattern 'B5' did not match any bands.

var collectionL5 = ee.ImageCollection('LANDSAT/LT05/C02/T1_TOA')
  .filterBounds(studyArea);
  

var collectionL8 = ee.ImageCollection('LANDSAT/LC08/C02/T1_TOA')
  .filterBounds(studyArea);


function maskL8sr(collectionL5) {
  var cloudShadowBitMask = 1 << 3;
  var cloudsBitMask = 1 << 5;

  var qa = collectionL5.select('QA_PIXEL');

  var mask = qa.bitwiseAnd(cloudShadowBitMask).eq(0)
      .and(qa.bitwiseAnd(cloudsBitMask).eq(0));

  return collectionL5.updateMask(mask).divide(10000)
      .select("B[0-9]*")
      .copyProperties(collectionL5, ["system:time_start"]);
}

function maskL8sr(collectionL8) {
  var cloudShadowBitMask = 1 << 3;
  var cloudsBitMask = 1 << 5;

  var qa1 = collectionL8.select('QA_PIXEL');

  var mask = qa1.bitwiseAnd(cloudShadowBitMask).eq(0)
      .and(qa1.bitwiseAnd(cloudsBitMask).eq(0));

  return collectionL8.updateMask(mask).divide(10000)
      .select("B[0-9]*")
      .copyProperties(collectionL8, ["system:time_start"]);
}

var imageCollection = collectionL5.merge(collectionL8).filterBounds(studyArea);



var stepList = ee.List.sequence(1984,2021);

var filterCollection = stepList.map(function(year){
  var startDate = ee.Date.fromYMD(year,5,1);
  var endDate = ee.Date.fromYMD(year,9,15);
  var composite_i = imageCollection.filterDate(startDate, endDate)
                        .map(maskL8sr)
                        .median()
                        .set('system:time_start',startDate);
  return composite_i;
});

var yearlyComposites = ee.ImageCollection(filterCollection);
print(yearlyComposites, 'Masked and Filtered Composites');




// // Add Enhanced Vegetation Index to a function and apply it.
// // EVI = 2.5 * ((NIR - Red) / (NIR + 6 * Red – 7.5 * Blue + 1))
function evi(img){
  var eviImg = img.select(['B5','B4','B2','B6','B3'],['nir','red','blue','swir1','green']);
  eviImg = eviImg.expression(
    '(2.5 * ((NIR - RED)) / (NIR + 6 * RED - 7.5 * BLUE + 1))', {
      'NIR': eviImg.select('nir'),
      'RED': eviImg.select('red'),
      'BLUE': eviImg.select('blue'),
      'SWIR1': eviImg.select('swir1'),
      'GREEN': eviImg.select('green')
    }).rename('EVI');
  return img.addBands(eviImg);
}

yearlyComposites = yearlyComposites.map(function(image){
  return evi(image);
});

print(yearlyComposites, 'With EVI as Band');

// Create image collection of yearly composites, selecting the EVI band.
var eviCollection = yearlyComposites.select('EVI');

But I am getting error: ImageCollection (Error) Error in map(ID=28): Image.select: Pattern 'B5' did not match any bands.

I know that the problem is in Image 28. While checking the bands I noticed that image 28 is empty.I also noticed that 28 image is a "transitional" image between the L5 and L8 collections. Image28 Can it be possible that somehow while merging two image collections they overlap each other ending up with empty image inside.

Aleksandra Melnik
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1 Answers1

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Try 'SR_B5' instead 'B5'

bands info:

SR_B1 SR_B2 SR_B3 SR_B4 SR_B5 SR_B6 SR_B7 SR_QA_AEROSOL ST_B10 ST_ATRAN ST_CDIST ST_DRAD ST_EMIS ST_EMSD ST_QA ST_TRAD ST_URAD QA_PIXEL QA_RADSAT

CV S
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