CALCULATE NDVI OF SENTINEL 2 IN GOOGLE EARTH ENGINE 

increase cloud cover for that image of your area of interest

var S2 = ee.ImageCollection("COPERNICUS/S2_SR") .filterDate('2020-02-01', '2020-02-28') .filterBounds(AOI) .median(); // print(S2); //COMPUTE NDVI var NIR = S2.select('B8'); var RED = S2.select('B4'); var ndvi = NIR.subtract(RED).divide(NIR.add(RED)).rename('NDVI'); var NDVI = ndvi.clip(AOI); var ndviparam = {min: -1, max: 1, palette : ['Blue', 'yellow', 'green']}; Map.addLayer(NDVI, ndviparam, 'NDVI');

This happened to me also cause I spelt palette wrong accidentally put in two Ls

please review min and max value and have you add visualization variable to map.addlayer

var S2 = ee.ImageCollection("COPERNICUS/S2_SR") .filterDate('2020-02-01', '2020-02-28') .filterBounds(AOI) .median(); // print(S2); //COMPUTE NDVI var NIR = S2.select('B8'); var RED = S2.select('B4'); var ndvi = NIR.subtract(RED).divide(NIR.add(RED)).rename('NDVI'); var NDVI = ndvi.clip(AOI); var ndviparam = {min: -1, max: 1, palette : ['Blue', 'yellow', 'green']}; Map.addLayer(NDVI, ndviparam, 'NDVI');

email me

email me

var S2 = ee.ImageCollection("COPERNICUS/S2_SR") .filterDate('2020-02-01', '2020-02-28') .filterBounds(AOI) .median(); // print(S2); //COMPUTE NDVI var NIR = S2.select('B8'); var RED = S2.select('B4'); var ndvi = NIR.subtract(RED).divide(NIR.add(RED)).rename('NDVI'); var NDVI = ndvi.clip(AOI); var ndviparam = {min: -1, max: 1, palette : ['Blue', 'yellow', 'green']}; Map.addLayer(NDVI, ndviparam, 'NDVI');

share your email address

var S2 = ee.ImageCollection("COPERNICUS/S2_SR") .filterDate('2020-02-01', '2020-02-28') .filterBounds(AOI) .median(); // print(S2); //COMPUTE NDVI var NIR = S2.select('B8'); var RED = S2.select('B4'); var ndvi = NIR.subtract(RED).divide(NIR.add(RED)).rename('NDVI'); var NDVI = ndvi.clip(AOI); var ndviparam = {min: -1, max: 1, palette : ['Blue', 'yellow', 'green']}; Map.addLayer(NDVI, ndviparam, 'NDVI');

var S2 = ee.ImageCollection("COPERNICUS/S2_SR") .filterDate('2020-02-01', '2020-02-28') .filterBounds(AOI) .median(); // print(S2); //COMPUTE NDVI var NIR = S2.select('B8'); var RED = S2.select('B4'); var ndvi = NIR.subtract(RED).divide(NIR.add(RED)).rename('NDVI'); var NDVI = ndvi.clip(AOI); var ndviparam = {min: -1, max: 1, palette : ['Blue', 'yellow', 'green']}; Map.addLayer(NDVI, ndviparam, 'NDVI');