Skip to main content

Questions tagged [evi]

The enhanced vegetation index (EVI) is an 'optimized' index designed to enhance the vegetation signal with improved sensitivity in high biomass regions and improved vegetation monitoring through a de-coupling of the canopy background signal and a reduction in atmosphere influences.

Filter by
Sorted by
Tagged with
0 votes
0 answers
13 views

Trying to export a time series of EVI values for a large asset in Google Earth Engine

I'm trying to export a time series of EVI data for a large asset containing 40,000 points. I am using the MODIS data. The code that I've written works when I extract data for 5 points, but it's not ...
Lauren's user avatar
  • 1
1 vote
3 answers
67 views

Why do I have EVI values out of the range?

I'm using Landsat 5 and 8 images to calculate EVI in Google Earth Engine. For what I read, the range of EVI is between -1 and +1 but I get values higher than +1 in all the EVI images. I need to ...
Sarahi Flores's user avatar
0 votes
1 answer
53 views

Dictionary.get: Dictionary does not contain key: EVI

I'm trying to write a script that calculates and retrieve EVI values from Sentinel-2 MSI in GEE then performs zonal statistics using points and export it .csv. I've written similar loop scripts for ...
Gaelle Tatiana Alexandrine Seh's user avatar
0 votes
1 answer
49 views

Displaying remote sensing imagery on GEE using Folium maps

I am a novice GEE user, and am just getting started with analyzing satellite data using the Python API on Google Colab. I have successfully imported MODIS data and am displaying it using Folium, but ...
Noah Jacobs's user avatar
0 votes
0 answers
80 views

EVI differences between Landsat 5 and 8 (utilizing Collection 2 data within Google Earth Engine)

I am calculating the EVI changes from 1984 to 2023 in the winter months within the state of Maine. I have written up a script to understand the changes within each month across the 40-year time scale ...
Sarah's user avatar
  • 11
1 vote
1 answer
161 views

Filtering clouds and creating median with Google Earth Engine Landsat8 EVI Composite

I am downloading images from Google Earth Engine's Landsat 8 Collection 1 Tier 1 8-Day EVI Composite collection here. I would like to create one image, a median composite of the images from May 1st to ...
Lavendarfire's user avatar
0 votes
1 answer
130 views

Downloading EVI from Google Earth Engine

I am trying to download images from Landsat's EVI collection off of Google Earth Engine. I saw another similar post here: EVI or NDVI collection image download that talked about the same issue. One ...
Lavendarfire's user avatar
0 votes
1 answer
357 views

Unable to transform edge error when clipping ImageCollection in Google Earth Engine

I am attempting to clip an ImageCollection in GEE, but I keep getting the error "Unable to transform edge (43200.000000, 1.476288 to 43200.000000, 1.477361) from SR-ORG:6974 PLANAR [926....
KAR's user avatar
  • 3
1 vote
0 answers
87 views

How do I produce a table of greening/browning trends for polygons I drew on my map?

I managed to create a Sen's slope map layer for my whole study area for Greening/Browning trends across a national park (I added a map of this below) but I am struggling to pull out greening/browning ...
sofii's user avatar
  • 11
1 vote
0 answers
54 views

Detecting trends in values of images' metadata in image collection using Google Earth Engine JavaScript API

I am beginner in javascript and in GEE. So far I made a script for calculating the mean EVI value of images inside an image collection and adding the value as a metadata for each picture. Now I would ...
Cosmeeen9's user avatar
0 votes
1 answer
1k views

Google Earth Engine Creating a mask for an ImageCollection

I'm using Google Earth Engine's JavaScript API to process Sentinel-2 images. I've calculated the EVI from the Sentinel ImageCollection, and would like to apply a mask that removes all the values ...
Beck's user avatar
  • 301
0 votes
1 answer
248 views

Google Earth Engine Limiting Image Values

I'm using Google Earth Engine's Javascript API to process Sentinel-2 images from 2016-2021. I've calculated the EVI values for these images, which has a range of -1 to 1. I want to correct any ...
Beck's user avatar
  • 301
0 votes
0 answers
174 views

Why do I get wrong NDVI, EVI values in crop monitoring?

I have been monitoring agriculture lands with Sentinel-2 S2MSI2A data. I'm calculating NDVI and EVI for the vegetation. The NDVI values are slowly increasing because the growing crops which is look ...
GeoKapor's user avatar
-1 votes
1 answer
273 views

Help: area code download in Google Earth Engine

I need help exporting this data. I don't know how to make the line of code to download. I think the error is in image: s2,, right? Code: var addEVI = function (image) { var EVI = image.expression( ...
patc19's user avatar
  • 1
1 vote
1 answer
663 views

Landsat 5 EVI in Google Earth Engine

I used this script for Landsat 8 and it worked fine, I've changed the band info for Landsat 5 but now I get this error: ImageCollection (Error) Error in map(ID=0): Image.select: Pattern 'B4' did not ...
Chelsea_VictoriaS's user avatar
3 votes
2 answers
6k views

Google Earth Engine Selecting one image from ImageCollection

I'm calculating the EVI of the COPERNICUS/S2 Sentinel-2 dataset on Google Earth Engine. I'm testing exporting my results, and want to view particular images in my processed ImageCollection (called ...
Beck's user avatar
  • 301
1 vote
1 answer
901 views

Google Earth Engine Mapping expression over Sentinel-2 dataset

I'm using Google Earth Engine to map an expression over a Sentinel-2 dataset. I want to calculate the EVI for an entire year of a particular area. My code is: /// Add EVI using an expression. //Make ...
Beck's user avatar
  • 301
-1 votes
1 answer
1k views

Google Earth Engine Dividing an ImageCollection by a constant

I'm using GEE to calculate the EVI of Sentinel-2 images in a specific area. To do this, I need to divide the Sentinel-2 images for scaling purposes. I'd like to use ee.ImageCollection.map, but as a ...
Beck's user avatar
  • 301
1 vote
1 answer
497 views

Google Earth Engine Map.addLayer failing to add bands

I'm working on calculating the Enhanced Vegetation Index (EVI) of a Sentinel-2 image in Google Earth Engine. My code is: //evi visual parameters var evivisparam = {bands: ['B4', 'B8', 'B2'], min: -...
Beck's user avatar
  • 301
1 vote
2 answers
188 views

Extracting NDVI and EVI in Alaska (EVI is showing -2 to 2 values)

I am working on extracting NDVI and EVI across the Landsat 8 collection in Alaska. Everything seems to be going swell, except the calculated EVI values are going from -2 to 2 instead of -1 to 1. I ...
James Lamping's user avatar
1 vote
1 answer
2k views

Calculating Enhanced Vegetation Index (EVI) using Sentinel-2 Level 1C, value problem

I am trying to calculate EVI values from Sentinel-2 Level 1C. When I calculate the EVI with this formula : (2.5 * ("Band 8" - "Band 4")) / ("Band 8" + (2.4 * "Band 4&...
kermit's user avatar
  • 11
0 votes
0 answers
855 views

Extreme values of Enhanced Vegetation Index (EVI)

I am looking to calculate a number of vegetation indices for use in a time series across Landsat sensors. I used the function below to map the formulas across the Landsat 7 and 8 Collection 2 Level 2 ...
Clayton Glasgow's user avatar
-1 votes
1 answer
161 views

My EVI index code doesn't work properly [closed]

My code for computing EVI index in google earth engine show EVI amounts for some dates very high or very low. I don't know what to do with this issue: //landsat8 EVI_2013_2020 var landsat8forEVIKoohin ...
soroush's user avatar
4 votes
1 answer
820 views

What is the appropriate input scale factor for EVI?

I am trying to calculate the Enhanced Vegetation Index using Landsat surface reflectance data. The formula for EVI using standard constants is: EVI = 2.5 * ((NIR – Red) / (NIR + 6 * Red – 7.5 * Blue + ...
Christopher's user avatar
0 votes
1 answer
1k views

GEE: subtract not a function

I tried to do calculations for 2 dataset of EVI on different year. I got an error message evi2020.subtract is not a function. The code is below var countries = Indonesia var Nama_Provinsi = ['...
imstilllearning's user avatar
3 votes
1 answer
249 views

Classifying an image based on the EVI values of vegetation

I am very new at GEE, and I’m trying to classify an image based on the EVI range of various vegetation classes. For example, Bamboo may have a minimum threshold of 0.6712 and maximum of 0.776 EVI. ...
Kavya's user avatar
  • 31
1 vote
1 answer
357 views

Exporting a CSV of Mean EVI Landsat 8 Values using reduceRegion function from Google Earth Engine (GEE)

I am trying to export a CSV file from Google Earth Engine (GEE) that reflects the mean EVI value per census tract. I have script that does this exact thing for NDVI from Landsat 8 but cannot seem to ...
Paige Bro's user avatar
3 votes
1 answer
259 views

EVI or NDVI collection image download

Landsat 8 Collection 1 Tier 1 8-Day EVI Composite. I continued with the starting codes given by Google Earth Engine. I tried to solve my work by adding code to the rest of these codes. However, it ...
CAGLAR's user avatar
  • 31
2 votes
1 answer
470 views

Exporting EVI image on Google Earth Engine with visual parameters between -1 and 1?

I am having an issue with exporting an EVI image with the visual parameters between -1 and 1. On Google Earth Engine (GEE), using the inspector tool, the values are between -1 and 1, but when I export ...
John's user avatar
  • 21
2 votes
2 answers
4k views

Calculating EVI in Sentinel 2-2A

I am trying to calculate EVI for a Sentinel 2 Level 2A image collection. I have applied the Sentinel cloud mask provided by GEE but am not sure I am applying EVI correctly because my range is not ...
Monica Quezada's user avatar
0 votes
1 answer
46 views

Quantifying mangrove condition over an 8 year period

Below is the script and I've also put an image of what it's meant to look like and what my image ends up looking like // The Landsat 8 top of atmosphere reflectance data var l8 = ee.ImageCollection(&...
Susan M Foster's user avatar
3 votes
0 answers
801 views

EVI in Google Earth Engine

I calculated the EVI for a Landsat image from -1 to 1. However, when I use the inspector tool in GEE and click around on my image, I see I have values less than -1. Is there something wrong with my ...
Grace's user avatar
  • 57
1 vote
0 answers
153 views

Quarterly composites for calculating NDVI and EVI

I am trying to create a code that could be helpful for making quarterly composites from 2013 to 2016 in order to calculate NDVI and EVI. I have figured out this code: var start = ee.Date('2013-01-01');...
Lam Nguyen's user avatar
1 vote
1 answer
1k views

Time series chart of EVI (Landsat 8) for a single pixel in GEE

I'm trying to chart out EVI for a single pixel(roi) over time. Basically trying to do what this link does for NDVI and apply it to the EVI available from landsat 8 imagery, but have no clue how to do ...
npopovic's user avatar
0 votes
1 answer
6k views

Calculate annual EVI vegetation index in Google Earth Engine

The code use for calculate annual EVI vegetation index in Google Earth Engine but there's a problem not define getEVI8 // Define Study Area -- MainProject var west = 21.691531038847305; var east = 21....
Faten Ragab's user avatar
1 vote
1 answer
304 views

Batch export of image collection giving consecutive numbers in filename

I want to use consecutive numbers in the name of the exported images from a image collection. I want to filter the MODIS image collection within a specific date range and region for the worst EVI ...
Torben's user avatar
  • 43
1 vote
2 answers
1k views

Calculation of Standard Vegetation Index from EVI for Image Collection in Google Earth Engine

I'm relatively new to scripting in the Google Earth Engine and have an issue with calculating the Standard Vegetation Index (SVI) for a MODIS image collection. I want to write a function, which uses ...
Torben's user avatar
  • 43
1 vote
1 answer
525 views

EVI2 function (GEE)

I wrote some code to calculate EVI2 from Sentinel2 imagery. But, I wasn't able to make it run as the .map() function seems to not work well with an image that has multiple bands. Error Message: img....
farhat's user avatar
  • 151
1 vote
1 answer
272 views

Is the Enhanced Vegetation Index normalized?

I am trying to figure out if the Enhanced Vegetation Index (2-band) is normalized or not? My first guess is that it is, but due to a multiplication factor of 2.4, I'm not sure if it is or not. The ...
ihb's user avatar
  • 493
2 votes
1 answer
395 views

Do Sentinel 2 Level-1C images need atmospherical correction before EVI calculations?

I would like to use Sentinel-2 Level 1C images to produce EVI maps using the following equation : EVI=G×(ρnir-ρred)/(ρnir+(C1×ρred-C2×ρblue )+L) Can I use the Level 1C image as it is, or should I ...
Marie-Charlotte's user avatar
1 vote
1 answer
748 views

Calculating EVI in ArcMap for Landsat 8 Image gives values ranging from 55155 to -23235 [closed]

How do I calculate EVI in ArcMap for Landsat 8 Image? My values are ranging from 55155 to -23235. I have tried using the formula: 2.5 * [(band 5- band 4)/ (band 5 + 6*band 4-7.5* band 2) + 1] I ...
Arpan's user avatar
  • 11
0 votes
0 answers
2k views

Enhanced Vegetation Index( EVI) Value Interpretation

Im working on calculation of Calculation of Enhanced Vegetation Index(EVI) From Landsat 5 TM and Landsat 8 OLI Using ArcMap 10.4.1. As far i know to Calculate EVI, first it needs to Convert the DN ...
Ashad Alif's user avatar
1 vote
2 answers
339 views

CRS errors whed reading MODIS NetCDF file

I am working with MODIS EVI 250m file in NetCDF format and trying to get the stack of EVI layers. So, I do: # check nc-file for variables names nc = nc_open(flist[1], write=FALSE, readunlim=TRUE, ...
DI S's user avatar
  • 21
1 vote
2 answers
2k views

stack() in R does not include all .tiff files in my directory

I am trying to perform stack() in R using enhanced vegetation index (EVI) time-series maps but it doesn't include all the .tiff files in my directory. Here's the list of files when I dir(files.evi): ...
mand3rd's user avatar
  • 161
1 vote
1 answer
685 views

Why mNDWI can detect the shallow water area but ignores the deep water area?

I'm using Landsat 8 in Google Earth Engine to detect the water body in Jiangsu and Zhejiang area, China. The formula is: mNDWI = (Green-SWIR)/(Green+SWIR) I applied this formula to GEE code, and it ...
Tsui Raymond's user avatar
1 vote
1 answer
2k views

Calculate water frequency in Google Earth Engine based on time series?

I have the Landsat 8 images cover southern Florida during 2017 (from Jan 1st to Dec 31st), with the cloud, scan edges and other bad observation pixels eliminated. I have also calculated several ...
Tsui Raymond's user avatar
1 vote
1 answer
314 views

Format GeoJSON use Join method before export in Earth Engine

After filter an LANDSAT-05 for an small area var Collection = function(pixel) { var colForPixel = ee.ImageCollection('LANDSAT/LM05/C01/T1') .filterBounds(pixel) .filterMetadata('CLOUD_COVER','...
Lilian Guimarães's user avatar
1 vote
1 answer
479 views

How to compute the conditional function and output binary image in GEE?

I am now using Google Earth Engine to process the Landsat 8 images. Now I have calculated NDVI, EVI, mNDWI and generated some maps. I am now want to generate a function based on those indices values, ...
Tsui Raymond's user avatar
1 vote
1 answer
152 views

Why is the difference between 005 and 006 versions of MOD13Q1 data?

I tried to repeat a project that used EVI in MOD13Q1. I failed and found that the project used the 005 version of MOD13Q1, and I can only download the 006 version on NASA's ftp. I compared the 005 ...
David's user avatar
  • 11
2 votes
1 answer
2k views

Obtain monthly and yearly average values of EVI using MODIS data on Google Earth Engine

I am currently trying to export and obtain rasters of EVI for: Every month of the year across 2000 to 2018 ie. If January has two MODIS EVI images, I would like to take the mean of the images for ...
Vijay Ramesh's user avatar
  • 1,342