Questions tagged [cloud-cover]

in this context cloud cover refers to the fraction of a remote sensing image obscured by clouds. Do not use for questions related to cloud services.

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2answers
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Filter Landsat images base on cloud cover over a region of interest

My goal is to create an image collection that has 100% free cloud over a small region of interest, for example a lake. This script filters landsat 8 images based on location and cloud cover: var ...
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3answers
3k views

Removing cloud from Sentinel 2A imagery?

I would like to use sentinel 2A imagery to look at canopy cover in Northern Vietnam. The only problem is that ALL the recent images have large amounts of cloud in the area I want to look at. Is it ...
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3answers
2k views

Is there a FTP to get Landsat images?

I need to automatically fetch Landsat images and for that it would be handy to access a ftp with images available. Does such ftp exist? Can I access it? Ultimately I want to get cloudless images.
6
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1answer
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How can I parse modis MOD13Q1 quality layers in R?

I'd like to parse MOD13Q1 VI quality layers in R. My original code must have been incorrect, because it gave lots of "deep ocean" flags in the middle of Brazil. After the changes suggested by Mikkel,...
5
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1answer
266 views

Chart of cloud cover over time

I am trying to create a graph with the cloud cover over time, per year. The following code gives me a graph, but I don't manage to get the dates on the x-axis line up chronological. Am I doing ...
4
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3answers
6k views

Creating Sentinel-2 cloud free, cloud-shadow free composite or scene on Google Earth Engine (GEE)?

Using this code, I am able to get a cloud-free composite, but it still includes shadows in my image. var collection = ee.ImageCollection("COPERNICUS/S2") .filterBounds(ee.Geometry.Rectangle(-85....
4
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1answer
6k views

Sentinel Cloud-free Collection Google Earth Engine Code Editor

I am trying to create and map an image collection (not image or mosaic if that is even possible), where QA60 defines the Cloud-mask. I have written the code below - however, it seems the Jan2016 ...
4
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2answers
682 views

AWS Sentinel 2 incorrect cloudy pixel percentage

For some tiles with low data coverage percentage metadata and tileInfo contain cloudy pixel percentage value equal 0. Examples: http://sentinel-s2-l1c.s3-website.eu-central-1.amazonaws.com/#tiles/37/...
4
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1answer
832 views

Cloudless days count with MODIS in Google Earth Engine

I'm trying to estimate the total of clear days in a year with the help of state_1km band in the MOD09GA product. But I'm not sure if it is right, also the possible counts are higher than expected when ...
3
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2answers
3k views

Do clouds reflect NIR/Red bands

When using Landsat 8 imagery to calculate NDVI, will the NIR and Red bands be affected by cloud cover? In other words, will clouds produce a wrong NDVI calculation?
3
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1answer
3k views

Apply cloud mask to sentinel 2 image in SNAP

I want to apply one of the cloud masks in the sentinel 2 file to the sentinel image. The sentinel 2 image I have downloaded features files concerning cirrus and opaque clouds at 10m, 20m and 60m. ...
3
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1answer
1k views

What is the difference between .filterMetadata(), ee.Filter.lte() and .sort() in google earth engine?

I am currently trying to obtain images that have less than 70% cloud cover (for example) and I have come across multiple variations of the same. Could you tell me what is the difference between these ...
3
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1answer
2k views

Google Earth Engine. How to get cloud cover score for each image in image collection?

I want to estimate cloud cover of each image in an image collection + would like to print out results for every image. I can see that cloud cover estimates are available for each image in their ...
3
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0answers
121 views

Google Earth Engine: Prevent Cloud mask algorithm for Landsat-8 from removing coastline lines

I'm a new Google Earth Engine user an I am trying to remove clouds on Landsat image using cloud mask. However, the cloud mask removes even the shoreline lines, not the clouds. I don't know why. Is ...
2
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2answers
2k views

Using cloud confidence to create cloud mask from Landsat 8 BQA?

I want to use the Landsat BQA (TOA images) to create a cloud mask in GEE. In particular I want to mask out all areas where there is high confidence that cloud cover is present. I have tried to adapt ...
2
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2answers
2k views

Shifting cloud mask in Erdas/ArcMap/Py Script [closed]

I have the task to mask out cloud cover in approximately 20 landsat 8 scenes. Creating the cloud mask for the "white part" is easy, but I need help in addressing the clouds shadow. General ...
2
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2answers
95 views

GEE error code while exporting Sentinel-2 cloud masked image

I have filtered a Sentinel-2 image and created a cloud mask for it based on its QA60 band. It works fine and displays with this mask applied. However, when I try to export it to a drive, I get the ...
2
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1answer
108 views

Landsat 8 cloud band: how to understand their (bit) coding?

I am trying to understand how to use the Lansdat 8 cloud quality band. The user guide L8_Surface-Reflectance-Code-LASRC-Product-Guide.pdf does not explain much, but just gives tables (Table 7-1, 7-2 ...
2
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1answer
2k views

Sentinel-2 cloud mask with fmask

I'm trying to run fmask on a Sentinel-2 granule. I downloaded the 3.2 version of Windows stand alone software for Sentinel 2 from https://github.com/prs021/fmask When I try to run fmask by calling the ...
2
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1answer
1k views

How to remove clouds with the cf_mask.tif file provided from landsat 8 surface reflectance data?

I just downloaded my first group of landsat 8 surface reflectance data files. In this package contains sr bands 1-7 (I hope to use some of these to create an NDVI) as well as numerous files called: ...
2
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2answers
525 views

Landsat 8 cloud detection without band 9

What is the best possible way to create a cloud mask of a Landsat 8 scene without using band 9? I think the best way will be to determine the cloud cover by thresholding in the Panchromatic band and ...
2
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1answer
75 views

Filtering clouds from average in Google Earth Engine

I am filtering a Sentinel-2 collection with the goal of producing an average over a period of three months. I have selected three images within the collection with which to do this. They all have some ...
2
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1answer
414 views

Computation Timed out error when creating a cloud-free composite of Sentinel-2

I am trying to create a cloud free-composite that covers my ENTIRE study area using Sentinel-2 data. But, everytime I run this code, I get a Computation Timed out error. I am simply loading an image ...
2
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1answer
776 views

Cloudfree images in small area from Sentinel-2

I have a similar question to this one here: Filter Landsat images base on cloud cover over a region of interest Different from the linked question I would like to find a more general solution that is ...
2
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1answer
1k views

Remove clouds in Sentinel 2A with R?

I would like to know how to remove clouds (create a cloud mask and its shadows) for Sentinel 2A data, using R (Windows). I have seen Information about this on Python or Matlab, but I work so far only ...
2
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1answer
837 views

Google Earth Engine. Looking for a way to have information for each location in the mentioned time period based on the non-cloudy layers

I am trying to work with landsat5 in Google Earth Engine and get some information for a list of locations (I have long/lat of the locations and their postal codes in a Fusion Table). I am looking ...
2
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1answer
452 views

Having trouble finding cloud cover data

I'm working on a project for a GIS course, I chose to find the best locations for the placement of an observatory. To accomplish this I planned to use cloud cover (or percentage of clear nights), ...
2
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0answers
249 views

Atmospheric correction of larger collection of Sentinel 2 L1C images (in Google Earth Engine) for NDVI time series

System: Windows 10 Software: Google Earth Engine browser, (QGIS, SNAP) Data: Sentinel 2 L1C & L2A, NDVI calculations I'm currently working on generating a NDVI timeseries in Google Earth Engine ...
2
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1answer
128 views

How to interpolate noise values on a landsat image time series using flag data?

I need to create a function to interpolate noise values on a landsat image time series by the mean on a time span of 2 (xt+1 and xt-1). I´m using the fmask product to detect cloud and shadow, then ...
1
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1answer
933 views

Getting rid of clouds from Landsat using ArcMap?

I want to calculate deforestation using Landsat 2 images. Right now I am using the raster calculator to generate a NDVI image and then the reclassification or Iso Cluster Unsupervised classification ...
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1answer
156 views

Cloud masking using sen2cor

I already have the SNAP 7, and I can’t run sen2cor 2.08 directly from it. However, I can alternatively use the command prompt but it can only take the L1C images as input. My problem now is that I ...
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1answer
279 views

Overlapping multiple images with cloud masked?

I am now using fmask algorithm to eliminate the cloud covered areas on Landsat images. I choose a period of time (Jan 1st 2017 to Dec 31st 2017), and selected the study area (Florida). I want to get ...
1
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2answers
243 views

maskClouds vs filter clouds on Google Earth Engine

On Lab 6: Time series analysis from https://developers.google.com/earth-engine/edu, there is maskClouds: var maskClouds = function(image) { var quality = image.select('BQA'); var cloud01 = ...
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1answer
908 views

Masking out shadows in Sentinel images using Google Earth Engine?

This question is an addition to this answer to Creating Sentinel-2 cloud free, cloud-shadow free composite or scene on Google Earth Engine (GEE)? There Rodrigo E. Principe showed how to mask out the ...
1
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1answer
2k views

Cloud cover percentage in Google Earth Engine

I'm doing a project at my university about the Cloud cover percentage in determinate areas in the world. I'm completely new to Google Earth Engine and I'm struggling a lot trying to find a solution ...
1
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1answer
2k views

Apply a cloud mask to a Landsat8 collection in Google Earth Engine - time series [duplicate]

I have tried to apply a cloud mask for a landsat 8 collection using code1, code2, and code3 but none will work. code1 encounters the error of not working even after changing var mask = img.select(['...
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1answer
303 views

Counting number of unmasked pixels per image in collection using Google Earth Engine

I'm trying to count the number of pixels that are masked by the cloud mask of the image collection given by the Earth Engine dataset. I have clipped my collection with a ROI and now I want to keep the ...
1
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1answer
58 views

How can I set multiple values to null in one raster and replace all other values with another raster?

I am working with Landsat8 cloud data (BQA.tiff). I would like to set all medium and high confidence cloud/cloud shadow values (values listed below) to null and replace all other values in this image ...
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2answers
715 views

Cloud Mask Landsat 7 Tier 2 TOA

I am trying to create a decent cloudfree mosaic of Landsat 7 Tier 2 TOA reflectance around the Amery Iceshelf in Antarctica. I did find a good script for landsat 8 TOA (Apply a cloud mask to a ...
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1answer
297 views

Quality of median image

I am trying to do supervised land use classification in a certain region. As this region is naturally prone to clouds, I have filtered the image collection on images with less than 10% cloud cover and ...
1
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1answer
406 views

Masking cloud pixels for NDVI in QGIS

I'm using QGIS to analyze some image of the NOLA area pre- and post-hurricanes. I'd like to calculate NDVI and a couple other indices for the images, but I want to exclude pixels with clouds in them ...
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1answer
2k views

Google Earth Engine - filter landsat by cloud cover over multiple polygons

I want to make a Landsat image collection that is totally cloud free over a SET of polygons. I have about 300 polygons (all within a single Landsat tile). I found this question, which is doing exactly ...
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1answer
1k views

Google Earth Engine: Finding least cloudy pixel of Landsat 8 images in ROI

I am having trouble cloud-screening Landsat 8 imagery in Google Earth Engine for a country with high cloud cover throughout the year. I have tried various techniques but unfortunately there is a ...
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1answer
307 views

What bands should be used to identify clouds using the cloud function of the landsat package in LANDSAT 8 scenes?

I am trying to use the clouds function of the landsat r package to identify clouds in my LANDSAT 8 scene. In the package help, it is said that reflectance bands 1 and 6 should be used: clouds(...
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1answer
2k views

Add a 'cloud' band to Sentinel 2 images (GEE)

This script is used to mask out cloud in sentinel 2 images using a threshold for band 4: // Sentinel 2 cloud function var cloudfunction_ST2 = function(image) { // If band 4 is higher than 2500, ...
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1answer
300 views

Cloud detection based on 4 bands

I have a series of satellite images in 4 bands (red, green, blue and NIR). What is the easiest way to estimate what percentage of each image is covered by clouds? The image is less than 1x1 km with 3-...
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1answer
325 views

How can I shift raster layer for making cloud-shadow mask?

I want to make cloud shadow mask in QGIS. I have raster cloud mask and I have to shift it by X,Y coordinates. Is there any easy solution?
1
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1answer
45 views

Limiting cloud estimation of Landsat8_SR over ROI in GEE

I intend to create an image collection of Landsat-8 surface reflectance not TOA that has 100% free cloud over my Region of Interest (ROI). Not surprisingly the code I have found in the forum ( Filter ...
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0answers
34 views

Sentinel-2 clouds filtering in GEE

I need to filter a Sentinel-2 image collection in order to have almost no clouds. I used the following code: //Dates of interest var START = ee.Date('2017-03-28'); var FINISH = ee.Date('2020-07-31'); ...
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1answer
76 views

How can filter low cloud coverange in a region with Sentinel-2 L2A in GEE?

I'm trying to filter clouds in Sentinel-2 through GEE in a ROI but I get the same number of images clipping or not clipping the geometry. How can I calculate the cloud coverage in a ROI and filter an ...