Questions tagged [ndvi]
Normalized Difference Vegetation Index is used to quickly identify vegetation and its condition in remotely-sensed data.
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Multiple Points showing up for for a given date after applying a Savitzky–Golay filter to smooth my data
I've been trying to draw NIR and NDVI data from LANDSAT and SENTINEL-1 data respectively, which can often be a little noisy. As such, I've been trying to apply the Savitzky–Golay filter available at:
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Does Landsat satellite image should have raster value to -1 and 1?
I am calculating the NDVI for Landsat-8 using the formula as shown below:-
But the pixel value rendered is as shown below: -
But the NDVI values need to be between -1 and +1 however, the value ...
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Getting code to export monthly NDVI values
I am trying to export monthly NDVI values for 2007 for my asset 'M2007' which is a mangrove extent shapefile. I've been able to export following the same code, the monthly ndvi values for 2012, apart ...
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I cannot export all image collection with image date for MODIS NDVI
While exporting images the namings are not setting properly with the image date. How can I solve the problem?
I have attached the associated code:
// Import the MODIS NDVI dataset.
var modisNDVI = ee....
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Exporting classified land cover class as an asset for NDVI calculations
I have conducted a supervised classification in Google Earth Engine using Random Forest, to which I have provided the code.
https://code.earthengine.google.com/3b3d4583f26a4651f4fbe10aa80c5f30
Map....
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EEException: Image.bandNames: Parameter 'image' is required
I am trying to compute the NDVI index using the MODIS Landset in Python and to visualize it in a time series chart, but I am facing an error and I cannot understand where is the problem. This is my ...
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Export Monthly Landsat NDVI Data from GEE
I am trying to export monthly MODIS Terra Daily NDVI data from Google Earth Engine (GEE). Despite researching various platforms, including this one, I find myself at an impasse. I attempted to ...
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GEE Landsat NDVI Composites - Are they cloud masked?
Anyone know how the Landsat NDVI composite image collections on Google Earth Engine are developed? I'm wondering if GEE masks clouds and cloud shadows? If they are performing a reducer on all NDVI ...
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Box plots in Google Earth Engine for NDVI
I am trying to create an NDVI chart with bix plots in Google Earth Engine. I drew an ordinary chart for NDVI and SAVI using LT5 images for 1992-2000. But when it comes to drawing charts with box ...
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Calculating LST from Landsat 5 in Google Earth Engine
I'm trying to write a code for Land Surface Temperature (LST) from Landsat 5 images in Google Earth Engine. I'm using the code of this question as a guide and I succeeded but I'm not sure to be right ...
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Doubt on using reducers with MODIS sinusoidal projection in Google Earth Engine
I am trying to extract the MODIS NDVI value for the pixel closest to a given point using the Python implementation of Google Earth Engine. The point is defined from Google Earth Coordinates (so WGS84) ...
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Monthly sentinel-2 Max and Mean NDVI, and B9 values extracted to CSV
When trying to run this code I get an error:
Expected Type: Image(unknown bands) actual type:ImageCollections
I would also like to maintain the ID column to be the ID column in my shapefile(labelled ...
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Extracting NDVI time series(1 year) from Sentinel 2_SR for multiple points and creating CSV files for them
I have a shapefile that has 1500 points. I am trying to extract 1-year time-series NDVI values from Sentinel 2_SR for each point and export it to CSV with NDVI values date-wise and existing UID column ...
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Visualize mean NDVI for the past 4 years Jan to Dec to distinguish cropland in GEE [closed]
My goal is to perform supervised classification in a large area using Landsat 8 images. Since the area has a lot of vegetation, it is challenging to accurately distinguish agricultural areas. To make ...
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Bamboo Index value for Sentinel-2 not rendering between -1 and +1
I created a composite band using last 5 years i.e., 2023, 2022, 2021, 2020, 2019 Sentinel-2 image for NDVI map and SI (Soil Moisture Index) map preparation. Then I created Bamboo Index (BI) map
from ...
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Different Band Values For NDVI Calculation For Composite Band
I created composite map using individual NDVI map of Landsat-8 from 5 years. However, I am confused with the NDVI value rendered after creating composite map. I got different values of NDVI for ...
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NDVI from Composite Band using ArcMap [duplicate]
I am using ArcMap.
I created a composite band for each 5-year using band i.e.,2,3,4,5,6,7,8. I then calculated NDVI index and created NDVI map for each 5 years. I now wanted to create NDVI map of 5 ...
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I want to test the statistical significance of the NDVI change in R
I have 20 Sentinel 2 satellite data for the period from 2017 to 2020, with 5 satellite scenes each for the months from May to September, covering one vegetation season. I am interested in whether the ...
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Extract Value to Points using ArcMap
I am using ArcMap.
I am trying to extract NDVI values to my point data. However, when I use the tool Extract Values to Points the error is generated as:-
I think they have same Projected Coordinate ...
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I want to apply Mann-Kendall test to NDVI of Sentinel 2 data in R
I have 20 Sentinel 2 satellite scenes from 2017 to 2020 with the months from May to September to cover the growing season. I calculated the NDVI of each scene and intersected it with my area of ...
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Maximum NDVI greenest pixel composites to create cloud free Landsat 8 images
I am utilizing maximum NDVI to get the greenest pixel of Landsat 8 data to create cloud free composites in the Google Earth Engine.
I found this GEE tutorial which is using Landsat 8 Top of Atmosphere ...
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Creating Graph for NDVI Raster using ArcMap
I want to represent the NDVI value creating Graph in ArcMap for the NDVI map as shown:
However, when I try to create a map for the NDVI values in ArcMap, the layer is not shown:
How can this issue ...
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NDVI time-series for multiple years in Google Earth Engine
I am trying to create a script and chart in GEE for NDVI time series for several years using
LANDSAT/LC08/C01/T1_32DAY_NDVI collection. I developed a short script using GEE library, but the chart ...
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Data column(s) for axis #0 cannot be of type string
I am trying to calculate NDVI using Sentinel 1, but when I tried to make a chart of it, this error is coming. Error, "Error generating chart: Data column(s) for axis #0 cannot be of type string&...
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How can I update this function to block out values of NDVI that are greater than or equal to 0.1?
Really new to JavaScript and Google Earth Engine, sorry if formatted badly. I am wondering if there is a way to only calculate an NDVI value that is greater than 0.1 in my .addBands line. If not, how ...
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Overlapping different year NDVI Map using ArcMap
I have created a NDVI time-series map for 5 different years. Now I want to prepare a combined raster band of the 5 years' time interval to form a single combined raster band.
How can this be done in ...
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Extract monthly NDVI (GEE)
I am currently writing code to extract a monthly NDVI for a specific polygon. I got the following code from a YouTube Tutorial and adapted it to my region and sensor. But it gets me the issue:
roi....
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Land Surface Temperature in GEE: Creating a Time Series Chart
I have this code below for creating a LST for my region. Then, I created a chart with mean values. But Chart is not showing the values in correct range. Values range is in between 2500 to 4500.
Code ...
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Calculating bamboo index
I am working on my project on bamboo distribution using RS. As per the literature, I found that bamboo indices is calculated as: BI = (NDVI-SI)/(NDVI+SI); Where NDVI is vegetation index and SI as soil ...
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I can't seem to get the classification for the 2010 LANDSAT
I've been trying to make a script that pulls 2010 and 2020 landsat images, calculate the NDVI from those images, then classify both of them to see the extent of change in vegetation in the area using ...
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Some of my LULCs do not show up in classification
I am trying to do LULC classification with seven classes using Landsat 8. when I finalize the classification, some classes do not show up in the report.
Here is the gee link https://code.earthengine....
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Harmonized Landsat-7 NDVI time series values are all the same when calculated with Google Earth Engine
I wanted to calculate the NDVI time series of multiple points using Google Earth Engine. I'm using Collection 2 Level 2 Landsat-7 and Landsat-8 imagery to calculate the NDVI time series. However, when ...
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Max pixel issue exporting NDVI map (Landsat 5 and 8) from GEE
I want to export an NDVI map for the Quebec province, Canada, from GEE so that I can select my sampling locations after importing the map on QGIS. But I get this error:
Error: Export too large: ...
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Landsat harmonization problem while exporting NDVI time series to Google Docs with GEE
I write a code that calculates the Landsat 7 and Landsat 8 Collection 2 Level 2 NDVI time series for given points and saves the results to Google Docs using GEE.
It was working well (I can get the ...
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Image.constant: Parameter 'value' is required
I am trying to calculate LST, for the time series, but it showing this error, "Image.constant: Parameter 'value' is required." My code link https://code.earthengine.google.com/...
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To add locations' name on top of the NDVI map in Google Earth Engine
I have visualized an NDVI map on GEE and added my plant specimens locations on top of that using the "asset" tab.
Now, I need to choose different locations inside and outside the city based ...
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Calculating LST and NDVI in Single Graph for comparison
I am trying to calculate the LST and NDVI mean values in a Single graph for comparison but somehow my code is giving an error:
Error in map(ID=1_0):
Image. select: Pattern 'NDVI' did not match any ...
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Mean NDVI polygon statistics Google Earth Enginee
I am creating a script to measure the mean NDVI of a series on a given date. I want the NDVI for each part of the polygon layer. I have developed this script that allows me to take images below cloud ...
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Removing pixels within given threshold in ArcGIS Pto
I have a time series of Landsat Tiles where I have attempted to mask out the clouds on each image and calculated NDVI but still get some outlier pixels.
Is there a way for me to remove outlier pixels ...
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Error while using Raster Calculator to calculate NDVI in QGIS
I exported 2 raster bands of Sentinel II (band 4 and band 8) to calculate NDVI (B8-B4)/(B8+B4), these 2 rasters are in EPSG:32630 - WGS 84 / UTM zone 30N. I'm currently using QGIS 3.26.1.
When I try ...
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Using geemap to apply Otsu's threshold on time series NDVI slope
I'm running geemap on Google Colab, and try to apply Otsu's threshold to a Sentinel-2 time series NDVI, the threshold is when the NDVI slope is greater than 0.5.
But when I try to apply the otsu ...
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Received too many arguments to function byFeature(). Expected at most 3 but got 4
I Used a boundary shapefile as geometry in Google Earth Engine, and got the error:
Line 37: Received too many arguments to function byFeature(). Expected at most 3 but got 4
How can I solve this ...
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Using the intersect function on pixel values from SampleRegions
I have a featureCollection of pixels (called "Pixel_values")from using sampleRegions and a feature collection of lineStrings (called "Hydro"), some of which intersect the pixels. I ...
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Calculate a Guassian standardized variable in Google Earth Engine
I wrote this script in GEE to calculate NDVI as well as the NDVI mean and standard deviation.
/**
* Function to mask clouds using the Sentinel-2 QA band
* @param {ee.Image} image Sentinel-2 image
* ...
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Google Earth Engine: only getting mean values for one point in a multi-year range
I'm currently using the code below to attempt to download a mean monthly NDVI value for different zipcodes in a state, and I am looking at a period of 4 years (so I would want around ~50 mean values ...
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Retrieving maximum NDVI for a year and associated date for each pixel in Google Earth Engine
I have been trying to generate a GEE script to generate two raster bands from a Sentinel-2 Surface Reflection collection.
The first band should have the maximum NDVI value per pixel for a whole year. ...
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How to calculate NDVI difference for two different time periods in QGIS
I have calculated the NDVI of an area of interest for 2015 (Landsat 8) and 2023 (Landsat 9) in QGIS. I want to detect NDVI change between the two rasters by subtracting NDVI values in Raster ...
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Managed aquifer recharge (MAR) and Remote sensing [closed]
What is the process to identify with quantitative data and remote sensing, how a managed aquifer recharge (MAR) has contributed to increased water availability, There is no local data and the area is ...
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Interpreting Green Chlorophyll Index vs NDVI
I am attempting to research the relationship between agricultural yields and household well-being, and I am using remote sensed vegetation indices calculated from LANDSAT images to do this. Whereas ...
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Make a NDVI Chart for two different locations
I made this code to make a chart of the mean NDVI of two different regions. But this code gives this error.
Error:
"Error generating chart: Collection.first: Unable to use a collection in an ...