Questions related to Remote Sensing Technology
How remote sensing is used in environmental protection and use remote sensing technology in managing natural resources?
I am trying to understand the limitations of the Simplified Surface Energy Balance (SSEB) approach and Landsat Collection 2 (C2) Provisional ETa Science Products to estimate actual evapotranspiration of different crops in various locations.
These would be used by an agribusiness to monitoring water consumption and water availability for crops (wheat, rice and corn) grown in 14 different countries
I am struggling to understand if and how these can be applied to different crop / locations couples as Landsat Collection 2 (C2) Provisional ETa Science Products are yet to be validated.
Thanks for your help,
I am seeking recommendations for established methods that utilize multispectral and Synthetic Aperture Radar (SAR) data for "Remotely Sensing Surface Water Bodies"
These could cover areas such as,
- Reflectance measurements
- Radiative transfer modeling
- Feature extraction
- Water Body Detection (WBD)
- Normalized Difference Water Index (NDWI)
- Modified Normalized Difference Water Index (NDWI)
- Automatic Water Extraction Model in Complex Environment (AWECE)
I would greatly appreciate any guidance or references that could be provided on this topic. Thank you in advance for your assistance.
I am using a NetCDF image comprising 12 subNetCDF images of different duration, as shown in the Figure attached; I tried to average/separate by using every tool, software, and different source, such as the use of Origin as mentioned in this link https://www.youtube.com/watch?v=14-sLHOaaOg&ab_channel=OriginLabCorp. I have used the Make NetCDF raster file tool, which won't import the subNetCDF in batch. It uploaded the images one at a time. I have used ArcGIS supporting tools such as https://r-video-tutorial.blogspot.com/2016/07/time-averages-of-netcdf-files-from.htmland also used python and R codes, but I failed to separate the subNetCDF files. I am working on large datasets. Uploading one-by-one images of multiple parameters with multiple duration will make my work more crucial, typical, and time-consuming. My work requires the final image as a raster file. Please recommend some solution to deal with the issue. Please help me get images at one or an average of all images in one. My work requires the final image as a raster file.
I'm doing a study based on compare two orbital sensors data, and on the study i'm basing on there is this normalization formula for the rasters: ((Bi<= 0) * 0) + ((Bi >= 10000) *1) + ((Bi >= 0) & (Bi < 10000)) * Float((Bi)/10000), Where "Bi" means "band". Is there someone who understad e could explain this formula? Thanks very much.
In a GIS environment
in remote sensing technology
Using satellite visuals to measure change over different time periods and detect spatial changes
Hello everyone! I'm doing a study based on comparing spectral indices from Sentinel-2/MSI and Landsat-8/OLI data. The Sentinel-2/MSI - Level-1C are provided on TOA reflectance data, and Level-2A on BOA reflectance data. However, Landsat-8/OLI data are provided only on BOA reflectance through Collection 2, Level 2. Considering that I have to convert the Landsat-8/OLI Collection 2, Level 1 data to TOA reflectance, do I need to do another type of pre-processing in all other data?
Dear colleagues I'm trying to calculate the land surface temperature for the Bakun Catchment, Sarawak, Malaysia region using different landsat satellite images of different years with the help of Google Earth Engine Code Editor. I'm not sure why I'm getting incomplete results for just this region and even the pixel values are too high in some of the years (please check the attached screenshots). Yes, for the NDVI and NDWI the results are covering the whole region.
I tried the same code for other regions of Pakistan and the results are very well.
So, my question is can anyone help me to get to know that this region the Bakun Catchment, Sarawak, Malaysia comes under special consideration or are there any other satellite data issues or maybe something wrong with the code? Also, does this region's LST goes down to -3 to -10?
I am performing a time-series analysis and using Sentinel-2 for the latest data and Landsat-5 for the older data. Now in the time-series graph, I see a significant rise in the output values for the last two years' data (sentinel imagery). The first step of my algorithm is to derive NDVI so does the difference between the two sensors still matter? If so then how to correct the process?
P.S- I am using top-tier products for all the imagery so is there a question of DN to TOA conversion?
I face a problem in LULC classification, like as an industrial area showing as a water body.
Please help me.
As is well, the remote sensing imaging technoloy reach an acceptable level of maturity and as shown in so many applications remote sensing can serve in so many areas. It came to my mind and the through the professional practice with different clients, some basic understanding of management from system theory perspective is required to well position the remote sensing technology within the business context. In other words, a business understanding is required to maximize the value proposition of remote sensing within the solutions chain. Your comments and opinions are highly appreciated.
We work in groundwater dependent region. Agriculture has been the largest consumer of the groundwater. In order to manage the groundwater, we have to manage agricultural groundwater use. In order to manage agricultural groundwater use, we have to monitor the cropping pattern in the village. What is the most accurate and cost effective method to find out the village level cropping pattern (season wise acreage of each crop grown)?
Does remote sensing provide any solution?
Is physical survey the feasible solution? Or is there any other solution?
If you have conducted any such study, please share the publication.
How do I measure the physical properties of marine waters using remote sensing technology and image processing?
I am trying to create an NDVI with a one-kilometer resolution. I have downloaded MODIS images and then I realized bands 1 and 2 of the images, which are used to create NDVI, come at a 250 m resolution. However, when I opened the 1km-resolution image I saw that a field is there named: "1km monthly NDVI", as in the picture below. What's more, I don't understand the "monthly" word in the name as the MODIS image I picked belonged to only one month! Furthermore, when I convert it to tiff and saw its value in ArcGIS, it ranged from -300 to 9000, instead of -1 to +1.
I have moved on to AVHRR to do what I need to do, but I really wanna know what it is.
The major applications, uses and purposes of civilian drones. How the world is transforming by the advancement of technology in mapping sector? How drone is aiding in mapping?
Do you know any example/case study using state of the art technology for waste management? (e.g., GIS, BIM, Computational tools, Computation Design)
We are working on Construction and demolition waste management in the built environment context, which one can be more useful for waste management in your area (e.g., construction, food, electronic waste etc.)?
We are working on the visualisation techniques and welcome to your participation.
I have using satellite image of Landsat 8 and 5 for LULC classification. I am confused that which software and method are the best for LULC classification?
Please help me.
Thanks and Regards
Models that evaluate parameters to water quality. For example clorofila a, turbidity, DO, etc.
Models for lakes in the tropical zone.
I want to extract RCS values or backscattering coefficients from available Radar imagery and create a Geospatial layer out of it.
I have been working in the field of forest research for a decade and a half so far.
I have experienced different events during submitting manuscripts and revisions and I think the process of reviewing manuscripts isn't fair and is only in the favor of the editors.
Let me explain a real situation, I have submitted a manuscript in "Arabian Journal of Geoscience" ( https://www.springer.com/earth+sciences+and+geography/journal/12517) on 12 Mar 2019 and today it has been 196 days since I made the mistake and the status of the MS is still "pending for editor". I have sent several emails to the editor and the manager, but mostly I receive no response or the same email which I think is only copy and past of the same text.
Now, my student so far has lost half a year and I can't even withdraw the ms.
I even sent springer "contact us' ID explaining the problem, but still, nothing happened.
I am really getting more and more disappointed to see that the whole process is mostly a marketing job rather than a scientific responsibility or an ethical act.
In these days, i want figure out what is suitable threshold value for extraction land from water bodies Using Modified normalize differential water index. I want determine boundary of shoreline precisely. So i need reflectance value of specially green band and SWIR2 band of thematic mapper for Sea water.
I am looking anyone specialist in monitoring water quality by RS & GIS can help me in discuss this question
All comments are welcome
Hello, I am currently doing research on shoreline mapping using remote sensing technology with tidal variation consideration. After mapping the shoreline changes using DSAS tools and determine the shoreline change rate with End Point Rate and Linear Regression output, I have problem in correcting the tidal data. I have searched on the one-line shift method and right triangle method but I have no idea how to do it. Can anyone shed some light to me?
Agricultural scientists especially soil scientist are measuring nitrogen use efficiencies in various crop varieties under different nutrient managements. Though this method has got more precision in measuring NUE, it is limited to small / specific area. In order to study N use efficiency in larger area with multiple crop varieties, remote sensing drone technology will be highly useful. Any study relating N uptake, N utilization or N use efficiency of the crop with remote sensing technology is invited for discussion and fine tuning the research proposals.
I have been trying to create raster images, but have been having issues in get to subset (extract by mask) to the same extent that I need. Initially I tried sub-setting them using a vector file but the results were not desirable. After some exploration on YouTube, I realized the need to use a subset raster image as the file for sub-setting other images. Still I can't get the favorable outcomes. Please suggest methods that can be used to create images with same extent.
Good day, senior colleagues, I need your help/ suggestions has to which spatial resolution satellite imageries/sensors can be your used to capture Lake ecological states. Also, if you could suggest a strong research methodology/ reading material regarding this, would go a long way.
Thank you everyone, in anticipation for your suggestions.
I have been trying to determine LST of a area of interest using MODIS level 2 NRT product MYD11_L2 . Previously I was using the standard 1km resolution level 3 product MYD11A1 for computing LST at a place. However since I need the data at a more real time basis I am exploring MODIS NRT products.
If somebody could help me or point me in the right direction as to how to determine LST of any place from the level 2 NRT 5 mins swath product MYD11_L2 it would be very helpful.
What do you think about how ortho- photos are made from historical analogue aerial imagery?
Suppose you have a set of analogue aerial images of several Flight Lines.
What software and methods will you use for ortho- photos production?
How to choose photo control points?
How do you measure the precision of the final ortho-photo?
I am interested in using Landsat 5-8 images to map snow and ice cover. I am trying to construct a time series showing how late into the year snow and ice cover lasts. I noticed that for Landsat ARD tiles obtained from USGS Earth Explorer there is a Pixel Quality Assessment band that accompanies surface reflectance products and that this PQA raster includes bit designations for pixels where snow or ice are present (bits 80 and 144 for Landsat 4/5). After reading more I have gathered that this PQA product is generated using the Fmask algorithm which was developed primarily for generating cloud masks. However, I decided to employ these products to see how they perform when generating fractional snow cover rasters.
I noticed that for some images very late into the year (May and June) the Fmask algorithm did classify many pixels as snow or ice, although after generating RGB composites and using the thermal infrared band to look at temperature, I determined that there was no snow or ice cover present in the image although it did look like some clouds were present. After reading more of the literature I found out that the Fmask algorithm has a tendency to sometimes classify cloud pixels as snow or ice, but I could not find an explanation as to why this happens. Is there a particular cloud type that the algorithm classifies as snow or ice, or is it unpredictable? Is there a better algorithm that is designed specifically for generating maps of fractional snow cover?
Thanks for you help,
I am trying to orthorectify an IRS 1C and an IRS 1D multi - spectral image using a DTM/ DEM. I have Cartosat 1 DEM of 1 Arc - Sec (30m). There are no RPCs provided by the vendor and I was told that the product isn't orthorectified nor geometrically corrected.
I use Erdas Imagine 2015 for working with Satellite Data. Any help on this will be highly appreciated.
There are many electronic triage algorithms founded in the literature for detect the emergency level of the patients. But which one are really used in the hospitals and clinics nowdays?
Dear Respected Researchers,
I would like to know that is it theoretically possible that satellite-derived surface reflectance at visible-to-shortwave wavelengths using the equation mentioned in the attached file can be greater than the top of atmosphere (TOA) reflectance, i.e. TOA reflectance - SR reflectance = Negative (mean difference)? If yes, then what are the possible reasons/conditions? Your answer supported by reference will be appreciated.
Do you use satellite imagery that needs to be corrected (radiometric, atmospheric & geo) or download the reflectance level "ready to go"?
In order to estimate the extent of rooftop area available for solar PV for domestic electricity demands, I am calculating the rooftop area of a district by extrapolating the rooftop to ground surface area ratio as calculated by randomly generated samples of clusters in Google Earth. So, I was interested if there are any pre-defined algorithm which might be more efficient for the same.
I'm looking for an environmental journal which has Impact Factor and NO paper processing fee. Currently I'm preparing an air pollution related paper for my academic publication.
Pls help provide a few names in which I can submit.
Thanks in advance, Shareful
I wish to utilize cartosat DEM, publicly available form bhuvan site. However, I have analyzed and seen that the elevation values from cartosat DEM are very similar to ellipsoidal height of GLAS/ICEsat altimetry data. Before I use the DEM data, I wish to know whether the elevation values show actual orthometric height or ellipsoidal height?
I am looking for a possibilities to download ASTERs new (2018 year) images with a good SWIR bands, because the earthdatas ASTER new images did not have Swir bands since 2008, i am interested it is possible to download 2018 year asters good swir bands?
In the name of God
Today, the development of remote sensing technology and geographic information system is so fast that quickly improves its applications in various sciences.
Since people, or , in other words, users are one of the important parts of the GIS system, the introduction of remote sensing and GIS to the public can increase the application and introduction of this branch of technology to various sciences with a twofold speed.
With this view, we have formed a group of social networks called GisAndRs that, beside all the talk and contents, introduces remote sensing and GIS to the public, more than the past.
So, we invite you to join this group, and while taking advantage of the posts, help us to enrich the content.
Here is the group link:
* i have collected soil samples during hyperion pass over the study area and chemical analysis was done.
* Lab spectral signatures has not taken.
* How can i correlate the chemical analysis results to hyperion data after preprocessing?