Questions tagged [modis]

Questions about data from the Moderate-Resolution Imaging Spectroradiometer sensors aboard the Terra and Aqua satellites.

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7
votes
1answer
333 views

Opening MOD17A3 in ENVI so it is properly georeferenced?

I am using ENVI 5.1 on Windows 8. I am trying to open a MOD17A3 (MODIS Net Primary Productivity standard product - L4) .hdf file which I downloaded from the USGS website. I am still a beginner at ENVI,...
4
votes
1answer
129 views

MODIS Fire Product tile conversion to GeoTIFF problem

I downloaded a tile (selected tile in the picture) from https://ladsweb.modaps.eosdis.nasa.gov/search/order/3/MOD14--6/2019-08-09/DB/Tile:H25V6 I used gdalinfo on the file. It's output is Driver: ...
3
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1answer
161 views

MODIS L1B reprojection and mosaic problem

I have been using MODIS L1B file to retrieve water vapor content. However, my study area is exactly between the gap between two images,just like this: I have tries ENVI MCTK extensions, HEG TOOLS, ...
2
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0answers
26 views

Accessing MODIS subdatasets from the command line?

FYI I'm new to command-line geospatial operations. I'm working with the MODIS BRDF-Albedo Quality product (MCD43A2) and am trying to: 1) do a simple gdal_calc.py operation to mask certain QA values ...
2
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0answers
290 views

Nonlinear regression in Google Earth Engine on each pixel in an image collection using GEE's servers

I am attempting to optimize the parameters for a double-logistic function on an annual MODIS NDVI time series in Google Earth Engine. I have previously looked at Non Linear Regression in Google Earth ...
2
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0answers
43 views

How to correct the deviation of reprojected MODIS L1B by using the gdalwarp?

I am working on reprojecting the MODIS L1B data which downloaded from the NASA EOSDIS Reverb website. The data is MOD021KM. I applied the gdalwarp command to convert the projection of the image to the ...
2
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0answers
628 views

Download HDF NDVI in R

I have a function to automate downloading NDVI data from https://e4ftl01.cr.usgs.gov/MOLT/ However, I'm hitting an error when downloading the .HDF files. They download fine but they seem to be ...
2
votes
1answer
158 views

Which output data type to choose in QGIS SAGA Raster Calculator in Batch Mode?

I have 5 years of MODIS13Q1 NDVI .tiff images for time series analysis. I want to multiply all the images with the scale factor of 0.0001 before using them. In order to process all at once I try to ...
2
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0answers
495 views

Get Modis tile from lat long

I'm trying to get the MODIS tile that I need, I can get it using online calculator http://landweb.nascom.nasa.gov/cgi-bin/developer/tilemap.cgi but I need to get it in code. How I can convert lat, ...
2
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0answers
55 views

Finding pre-processed MODIS products?

I am trying to recognize burnt areas based on some MODIS products and I just realized that I am missing a bunch pixels from the coastline masking. As you can understand that is an issue because I am ...
2
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0answers
38 views

minimum number of pixel points for regression on atmospherically corrected satellite images

I am performing atmospheric correction on a Landsat 8 image using different methods to check which one works best (in order to proceed with further/subsequent analysis). Wondering if it's okay to use ...
2
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0answers
319 views

TIMESAT seasonality data (MODIS EVI)

I am trying to get seasonality parameters from MODIS EVI (MOD13Q1) for Indonesia. I have loaded data from 2013-2015, but the plotted time-series is shifted from what I expect. Indonesia has rice-...
2
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0answers
198 views

16-day-MODIS NDVI values seem to be wrong compared to my soil moisture ground data!

I'm using MOD13Q1 product of MODIS for estimation soil moisture. As I know, this product is made up of the maximum value of NDVI of each pixel over 16-day calculated NDVI values. The problem is that ...
2
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0answers
187 views

Application of a Piecewise Logistic Function to Extract Seasonality Metrics

I am working with 16-day MODIS EVI (satellite) data and I want to fit a Piecewise Logistic Function through my 23 EVI data values. The following formula is for the Piecewise Logistic Function: y(t)= [...
2
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0answers
135 views

Flood extent extraction from satellite images

How can I extract the floodwater from satellite images? Is the image classification method accurate for moderate-resolution satellite (Terra/Aqua MODIS)? Or are there more accurate methods?
2
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0answers
808 views

Processing MOD35 cloud mask image?

I have a question about processing MOD35 cloud mask image. I worked reprojection on MOD35 cloud mask image using MODIS Swath Tool. The processed results of MOD35 cloud mask are consist of 6 band ...
1
vote
1answer
13 views

Google Earth Engine Export CSV MODIS Pixel Data for Multiple Polygons within a Rectangle

Having watched GEE tutorials, pieced together code from several StackExchange questions and received help from Kuik and Jobbo90 I managed to write a code for a MODIS/006/MOD11A1 surface temperature ...
1
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0answers
10 views

MCD12Q1 Quality Control

I am using ArcGIS Desktop. When using the MODIS MCD12Q1 IGBP classifications, is there any way to run accuracy assessment or Quality Control is the only way?
1
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1answer
27 views

Terra MODIS MOD11A1 LST values

I am having a hard time to figure out what this information refers to. It is stated at the product description of Terra MODIS MOD11A1 product (Wan et al.,2015). (from https://lpdaac.usgs.gov/products/...
1
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0answers
28 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, ...
1
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0answers
38 views

Reduce number of null values in MODIS surface temperature data

I am trying to reduce the number of null (no data) values in output data for an area (Tokyo prefecture) in August 2019 when using MODIS 1km spatial resolution daily surface temperature satellite data (...
1
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0answers
8 views

Filter collection with millis data on MODIS

I'm trying to split a modis collection in two others, using like a splitter a data time that's defined in millis. I don't want to do it manually. var maskMOD13Q1 = function(image) { var qa = image....
1
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0answers
25 views

Google Earth Engine: calculate number of weeks where SST over a threshold in past 12 weeks

I've been using the MODIS-Aqua/L3SMI dataset to investigate sea surface temperatures (SST) for a specific region. What I'd like to do is for a specific time epriod (could be day, week or month), find ...
1
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0answers
17 views

Problem merging/clipping MODIS rasters in QGIS

Im pretty new to QGIS and am having some trouble making a NDVI map for Mali. To cover the whole country I need 5 MODIS NDVI tiles, however every time I try to merge them I get a "the following layers ...
1
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0answers
33 views

Monthly Water Area Monitoring in Google Earth Engine?

I've computed water area for each 8 days for about 20 years. I don't know how can I compute monthly area for these years? or How can I change 8 days product to the monthly in this code? code link: ...
1
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0answers
26 views

Scaling factor for MODIS (MY09GA 006 or MYDTBGA 006) product for timeseries data

I was using Modis data (MYDO9GA) product for my research and I was following this document as a user guide. https://landweb.modaps.eosdis.nasa.gov/QA_WWW/forPage/user_guide/MOD09_UserGuide_v1.4.pdf ...
1
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1answer
79 views

Make a loop in Google Earth Engine for reduce NDVI from year a months?

I have this code, it generate N ImageCollection and for each image a chart from NDVI in function a the months This is the place of study: var areaEst = ee.FeatureCollection("users/aleszczuk/...
1
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0answers
16 views

Geo-Referencing level 1 AQUA data

I have a direct broadcast AQUA data. I used RT-STPS to extract the level 0 .PDS files and process them further to level 1A and level 1B using the modisL1DB software. These produce .hdf files. I can ...
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0answers
116 views

R MODIS MOD13Q1 - How to handle data quality issues?

I'm running into some issues with 250m 16-day MOD13Q1 NDVI data using the MODIS package in R. Looking at the following raster plot, there are certain days where the NDVI does not match the true ...
1
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1answer
221 views

Is MODIS sinusoidal tile boundary in Eathdata website real?

I was using MOIDS data MCD12Q1 (MODIS/Terra+Aqua Land Cover Type Yearly L3 Global 500m SIN Grid V00). I try to use PyProj in Python to transform the Sinusoidal projection to lat/lon. It actually ...
1
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0answers
337 views

Export image collection Google Earth Engine to Google Cloud Bucket Python API

I have an image collection within GEE's Python API that I want to clip and write to my google cloud bucket. I am working on a Google Cloud VM and have mounted my bucket "gee-bucket22" with gcsfuse. I ...
1
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0answers
39 views

Setting both spatial extent and resolution when using gdalwarp?

I would like to overlay two tiff image that orginally have different projections. One is MODIS sinusoidal and the other one is WGS84. I use gdalwarp to re-project the latter into the same projection ...
1
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0answers
15 views

Does Modis offer MultiYear statistics?

I'm trying to calculate the VCI data for my entire State. I'm using MODIS's 16 day NDVI Average. From this post, I see that I would need to calculate the Min & Max NDVI values for each pixel ...
1
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0answers
154 views

Dimensions of images given their latitude and longitude for Google Earth Engine

From the point long: 16.499050771335575, lat: -30.882 I want to find the corresponding latitude and longitude values that would result in a 200 km by 200 km square in which the aforementioned ...
1
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0answers
48 views

Opening MODIS Raster MOD13Q1 .hdf file comes in as Float32 instead of 16-bit signed integer

Trying to open a MODIS 16 day composite NDVI raster from the .hdf file. After selecting just the NDVI band, QGIS nicely displays the image. However, on this image the range of values is between -3....
1
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0answers
73 views

Creating Maximum-Value Composite of MODIS images using QGIS

I am trying to create a Maximum-Value composite of 4 MODIS images that are in .hdf format and I tried with 'Raster Composite' of ArcGIS but I think that's not the appropriate to do it. Can I do it ...
1
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0answers
43 views

How to Substract one image band from the subsequent in Google Earth Engine?

i am trying to find the day of year (doy) for each year with the highest change in NDVI compared to the day before, to map in the end a shift in start of season. My code to seperate each year so far (...
1
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1answer
91 views

Whether Sentinel 3 OLCI can be used as a MODIS replacement for 250m NDVI?

Based on the bandwidths MODIS bands 1 and 2 (620nm - 876nm) will match S3 bands Oa7 - Oa17 (620nm - 865nm) I am just trying to know if anyone had any experience in using S3 data instead of MODIS for ...
1
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0answers
127 views

rescale MODIS NDVI value- fill value and background value after clip study area

I want to use MODIS NDVI time series to extract phenological parameters using TIMESAT software. I have question about data prepration, Is it alwaysd necessery to rescale NDVI data? valid range in ...
1
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0answers
192 views

Reprojecting raster using QGIS?

I'm currently working on MODIS satellite product "MOD16A2" which provides regular 500m's resolution pixel of evapotranspiration. I basically need to extract from the map the mean value of different ...
1
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0answers
114 views

AOD measure from MODIS satellite images

I need to use the MODIS Terra images, in particular the daily data that contains information about Aerosol Optical Depth. What do i have to do is to obtain the value of AOD in some precise point(in my ...
1
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0answers
960 views

MODIS Projection Google Earth Engine

Why if I applied a code over a MODIS collection and then I download an image, the image is in WGS projection? The code is the next: // Simple regression of year versus NDVI. // Define the start date ...
1
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0answers
252 views

Binary cloud Mask from MODIS (MOD35_L2) using MRTSWATH

When the MRTSwath tool is fed with MOD35_L2 cloud mask HDF file, the tool provides six tif images (b0 till b5). Each tif file has 8 bit information. Are these 6 images somehow indicating the 48 bits (...
1
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0answers
143 views

Issue with mapping MODIS SIN grid to EASE 2.0 with gdalwarp

I am trying to merge and reproject MODIS 250m NDVI product (https://lpdaac.usgs.gov/dataset_discovery/modis/modis_products_table/myd13a3_v006) to EASE2.0 grid. I am interested in projecting these to ...
1
vote
0answers
46 views

How to use bitwise operator in ArcGIS desktop to extract required pixels?

MODIS QA dataset gives quality flags in decimal numbers that are required to be converted into binary format to assess data quality. For a 8-bit system of MOD15A5 image, the decimal values 16 and 97 ...
1
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0answers
65 views

Unable to produce tif files from two stitched modis tiles, i could not extract my bands of interest which are EVI and pixel reliability

Hi i am trying to stitch two modis tiles and also extract my bands of interest which are EVI and pixel reliability. the steps i took are as follows. loaded the files into ModisTool selected my bands ...
1
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0answers
142 views

Weighted average to make monthly LST in R?

How to make a monthly LST (MODIS) product from the LST day and LST night, knowing that it is a product of 8 days and some months are represented by four or more pictures in addition to the lack of LST ...
1
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0answers
460 views

Projecting MODIS LST (MOD11_L2) Data using GDAL (+ Python)

I am trying to analyse some MODIS LST data (MOD11_L2) and am having some difficulty projecting the files into WGS84. I know that I can use the MODIS Reprojection Swath Tools, but I am trying to do the ...
1
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0answers
110 views

view zenith angle of MODIS surface reflectance product and Landsat 8

I have a MODIS daily surface reflectance product (MYD09GA) which I'd like to validate Landsat 8 image with. I want to obtain pixels that only fall within the view zenith angle of Landsat 8 ( 0 - 7.5). ...
1
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0answers
50 views

How can I create a polygon(filled polygon) from a single pixel stored in a hdf file(MODIS)?

I'm working with MODIS data to get EVI. I'm following this question to get the required values of EVI. The hdf file has 4800x4800 rows/columns (250m). I can get the X,Y pixel coordinates and the ...