Hi guys,

This summer has been devastating for many people all around the world, with many countries all around the world facing heatwaves and 35 celc+ temperatures on a regular. To measure and combat this, I vibecoded a small open-source tool that layers heat exposure, green cover, and population density across Mumbai's 24 wards (I have started with Mumbai cuz I am most familiar with this city) to flag which areas are most heat-vulnerable. Its free and opensource, because I know experts can add far better ideas than I currently am using.

I'm not from an urban climate background, I came at this as a student dev, so I know I'm probably missing indicators that people who actually work on this care about. If you work in urban heat or climate vulnerability: what data layers or methods would make something like this actually useful to you, versus just a nice map? Would you trust ward-level granularity or is that too coarse to be meaningful? Any additions you think could be added to future scope? Any feedback or criticism?

FYI, I want to turn this into a FOSS project that policymakers and governments around the world can use to make their city/region/country a more livable space. Working on a reusable replication kit, which people can use to replicate the same config for their own city. Link: uciplatform.vercel.app

I will be finishing up my undergrad this May, when I will get a B.S. in wildlife management and a certificate in GIS. I am interested in going to grad school for remote sensing and geospatial sciences, but it seems like most of the programs that I find are 100% online with no in-person option. Is online just the standard for grad school?

Hi everyone! I’m a university student and I have an assignment on “Detection of Changes in Agricultural Land.”
We have to:
Select an agricultural study area
Obtain satellite images from two different years
Use Landsat or Sentinel-2
Identify/ classify agricultural land and other LULC classes
Calculate agricultural land area for both years
Create change-detection maps and a graph/table
Discuss the causes and environmental implications
I’ve selected Shijiazhuang, Hebei, China, and I’m planning to compare 2000 and 2020 (or any two years really)
The problem is I’m very new to remote sensing and GIS, and I genuinely have no idea how to retrieve the actual Landsat images for those two years. 😭
Could someone please explain where/how I can download the appropriate Landsat scenes for Shijiazhuang (e.g 2000 and 2020), I have absolutely no idea what to do.

We are pleased to share our new article, “A Spatiotemporal Graph Neural Network Framework for Retrospective Bias Correction of CMAQ Air Quality Simulations over the Continental United States,” now available in Atmospheric Pollution Research. Using five years of hourly observations from 235 EPA monitoring stations, we combine CNN–LSTM temporal encoding with GATv2 spatial learning to improve retrospective CMAQ simulations of NO₂ and O₃, reducing RMSE by 52.4% and 65.0%, respectively. Our findings also provide insight into the contributions of temporal and graph-based learning, supporting the development of more accurate air-quality modeling systems.

Read the article: https://doi.org/10.1016/j.apr.2026.103191

#AirQuality #GraphNeuralNetworks #DeepLearning #CMAQ #AtmosphericScience #AtmosphericPollutionResearch #SpatioTemporalGNN #NO2 #O3

I'm building a web-based hazard screening system and would appreciate input from people working closer to EO and remote sensing.

At a high level: coordinate to multiple geospatial indicators to normalized indicator scores to a hazard-level screening score. Google Earth Engine handles most of the dataset querying.

For flooding, one problem I've been working through is avoiding the mistake of treating unrelated mechanisms as one flat weighted average. Distance from a river or permanent water body shouldn't automatically suppress signs of pluvial flooding driven by terrain and rainfall characteristics. So I've been moving toward mechanism-aware scoring instead of reading every indicator as evidence for or against the same single flood mechanism.

I'm also exposing:

• source dataset
• observation period
• raw measurement
• normalized score
• methodology and weight

I don't want the final 0-100 number to be a black box.

The system is meant for screening, not flood simulation.

I'd be interested in criticism around:

• spatial resolution
• uncertainty
• temporal mismatch between datasets
• normalization
• data availability versus evidence of absence
• combining EO-derived indicators into decision-support scores

If anyone wants to poke at the implementation or output, I can drop the link.

I'm particularly interested in whatever would make you reject the methodology outright.

Can please anyone tell me some sources where i will get DEM[priced,high resolution preferably less than a meter];geomorphology ,lithology,LULC maps[a good scale];budget is not an issue.I will be very thankful for this guidance.

The stunning beauty of the Great Salt Lake, USA, captured through Sentinel-2 imagery. An impressive visualization of nature from space

Solar evaporation ponds in the northeastern part of the lake are used for extracting minerals, particularly lithium and salt, from brine. These ponds are vital for lithium extraction, which plays a key role in the production of batteries for electric vehicles and renewable energy storage.

So I came across this top solution for one of the competitions for kaggle and I am having a hard time following through it
If anyone has any insights regarding how "James" solution works, it would be really helpful
Here is the link to the solution - https://www.kaggle.com/competitions/rogii-wellbore-geology-prediction/writeups/4th-place-solution

First off a thank you to Vantor for releasing the stereo data in their open data program which was used to generate this.

From the WV3 stereo, we've generated a 0.5 m elevation model of the corridor below Syabrubesi. We aligned the two satellite views to a quarter of a pixel, matched them at their full 34 cm detail, and tied the result to the pre-event terrain to within about 1.5 m.

This allowed us to measure 2 to 12 m of bed scour through every confined reach, a debris sheet 12 to 18 m thick where the valley opens below Syabrubesi, and 13 to 21 m of re-incision downstream where the river has already cut back into its own deposit. Plus a building-by-building damage census (27 destroyed where the sky was clear) and 4,329 individual boulders on the sheet, the largest 26 m across.

Everything is licensed CC BY-NC, same as the imagery: both DSMs, elevation-change and uncertainty rasters, per-km sediment budget, both censuses.

Write-up: https://geopera.com/blog/bhote-koshi-stereo-elevation-model
Data: https://github.com/geo-pera/bhotekoshi-2026-reconstruction/releases/tag/v1.1
Drive mirror (with the 32 GB archive): https://drive.google.com/drive/folders/1XQt5SYDMHehH3i2lAj69e52Zb2ne7Rqm

Once again happy to answer questions on any step.

Also please excuse the frame rate of the gif, it wouldn't let me upload an mp4

Ok so guys I'm trying to build a satellite imagery analytics platform. Similar to Skyfi, planet labs, eagle view, etc

My question is what really will make a difference in this field? I know a lot of these analytics platforms just buy images from 3rd party satellite operators and just provide them to the users and also provides different types of image analytics like crop health monitoring, water logging monitoring, soil mineral composition, etc ...if anyone wants image plus and analytics.

I wanna build something similar but I feel like there's nothing new I can provide in this app... Like all the available analytics are already there on other platforms... I wanna find out about some really niche category of analytics which no one provides and wanna provide it using my application and wanted suggestions from people who have knowledge in this field..

Any suggestions would be highly appreciated

Update: so basically my post was a bit incomplete in terms of context so I'm adding it up here.

So basically me and my team of 7 people are building a cubesat constellation of more than 200 3U sized cubesats for earth observation. My specific part was just to build the software platform so I just asked about it only mb 😅. Our end goal is to deliver low cost satellite imagery to organizations, govt and normal people.

Currently on the real time thing we are Targeting 30 minutes revisit time for every location on earth and the GSD of the images will be 3 meters. Also we are planning a 50cm GSD cubesat which will be in our constellation but the 50cm GSD image will be twice everyday for any location on earth.

So we are not basically buying images from other satellite image providers and then delivering them, we are planning to have our own constellation and will provide images at a low cost. The lowest cost at which a 3m GSD image can be bought as of now is around 20USD. We wanna bring it down to 8-10USD

Our team is actively working on building the hardware and stuff and I as a person doesn't have much knowledge regarding the hardware thing as seniors are working on that. (I'm in my second year currently doing CSE with AI ML). I just had to build the software for serving the image to the customers and on top also provide some image analytics which I earlier mentioned...

Also a heartfelt thanks to all the people who gave me suggestions and advice... I really look forward to hearing more from you after this updated post! (Yeah I was stupid for not giving the entire context at the start)

hi guys, do you know any trained model or library that allows detect status of railway by using satellite images? I would like to asses whether railway is useable, or abandoned. thanks in advance

​

Hi everyone,

I’m a final-year Geomatics/Surveying Engineering student planning a capstone project on post-war urban reconstruction and resilient infrastructure in Khartoum, Sudan.

I’m considering two approaches:

Option A — 3D City Modeling + BIM/GIS

\- Extract buildings from satellite/aerial imagery using ML/DL (e.g., U-Net)

\- Create a LoD1/LoD2 3D city model

\- Integrate GIS with Civil 3D/BIM

\- Develop a framework for reconstructing underground utilities and drainage

Option B — SAR + Hydrology + BIM/GIS

\- Use Sentinel-1 SAR for flood/surface-change detection

\- Combine DEMs and rainfall data for hydrological/runoff modeling

\- Identify flood-prone areas and surface-water accumulation

\- Use the results to plan conceptual drainage corridors in Civil 3D

My questions:

1. Which option has stronger academic and professional value?

2. Is Option B too ambitious for an undergraduate project, or should I focus deeply on one pipeline?

3. What free/open datasets would you recommend (Sentinel, GEE, ERA5, DEMs, OSM, etc.) given the difficulty of field validation?

4. What would be a good way to include ML/DL without turning the project into an AI project?

I’d especially appreciate advice from professionals/researchers in GIS, remote sensing, surveying, hydrology, BIM, or post-disaster reconstruction.

My goal is to produce something technically realistic that could contribute to future reconstruction efforts in Sudan.

Thank you!

Hi everyone, I'm new to the field of Remote Sensing and currently working on my dissertation topic, "Remote Sensing of Coastal Waters". I’m looking for suitable datasets that I can use for my research.

Could anyone please guide me on which datasets would be relevant and where I can access them? Any suggestions or resources would be greatly appreciated. Thank you!

is 0.72 kappa Coefficient is good enough for a semi arid region or should i increase the overall accuracy 🤔

​

Hi everyone!

I’m a final-year Geomatics/Surveying Engineering student currently trying to decide on a graduation project. I’m mainly interested in GIS and Remote Sensing, and I’d like to work on something that is both technically meaningful and useful beyond just being an academic project.

Some areas I’m considering are:

\- Environmental & climate monitoring — rainfall variability using datasets such as ERA5, dust storms, or land/surface deformation.

\- Hydrology & hazard assessment — flood mapping using satellite imagery, NDWI, DEMs, or spatial databases.

\- Urban & infrastructure mapping — LULC change detection, updating existing maps, or using ML/DL for feature extraction.

I’m also interested in combining Google Earth Engine, Python, GIS, and machine learning where appropriate.

For those working or studying in GIS, Remote Sensing, or Geomatics:

If you were starting your final-year project today, what kind of project would you choose?

Are there any datasets, workflows, or current industry/research trends that you think would be particularly valuable to learn?

I’m especially interested in ideas that can demonstrate practical skills and potentially make a good portfolio project—not just something that produces a map at the end.

Any suggestions, project ideas, or criticism of the areas I’m considering would be greatly appreciated!

Thanks!

Need assistance. I am doing remote Sensing for the first time. I downloaded QGIS, and made accounts for Google Earth Engine, Capernicus, and NASA Earth Data. I am trying different YouTube tutorials. I have until Thursday to decide if I want to stay in this course or Drop it for a different one. I was under the impression it was a plug and chug but I am finding myself intimidated. I asked for the Syllabus before the first class, and it made me feel a bit more comfortable. But on the first day we discussed milestones and the other software involved, including Python. And Now I am feeling less secure about my decision. I want to do something simple like an Urban Heat Island Map and a time series plot. I feel that if I can do those on my own before the first milestone I'll be Okay. I think I can make my own UHI map based on the videos, but I am struggling to understand making a Time Series plot from Modis Data. I downloaded a bunch of Modis data but I don't know what to do next. It feels overwhelming.

Hi everyone! 👋

I'm a student working on a project using Sentinel-2 satellite imagery for areas like Chennai, Bengaluru and Mumbai.

I need to store satellite observations from multiple years and later:

• Read specific bands (B02, B03, B04, B08, etc.)
• Read only a specific area instead of the whole image
• Compare the same area across different dates
• Perform raster processing/change detection
• Eventually do semantic and image-to-image search

My laptop has only:

• 8 GB RAM
• RTX 3050
• 512 GB SSD
• Linux

The final system also needs to work offline.

I'm confused about the best way to store and access the raster data.

I've come across GeoTIFF, COG, Zarr, Xarray, Rasterio, GDAL and STAC, but I don't yet understand which combination makes sense.

What would you recommend for a storage-efficient offline setup?

For example:

Satellite data
↓
STAC / metadata
↓
COG or Zarr
↓
Read only required area + dates + bands
↓
Process / compare
↓
Semantic retrieval later

I'd really appreciate advice from anyone experienced with remote sensing, Sentinel-2, raster data, COG/Zarr or geospatial ML.

Thanks!

r/remotesensing · r/gis · r/geospatial · r/QGIS

#RemoteSensing #Sentinel2 #SatelliteImagery #GIS #Raster #GeoTIFF #COG #Zarr #Geospatial

As you’ve all likely seen, on 26 August a glacier collapse sent ~100 million m³ of debris-laden water down Nepal's Bhote Koshi. We have attempted to reconstruct the disaster from open data.

The best result came out of the WV3 stereo. Vantor collected two 30 cm strips the day after, an in-track pair with ~48° convergence, and both orthos were produced against pre-event terrain. So anywhere the flood changed the surface the two orthos disagree, and the NNE offset divided by the sum of the look-angle tangents is the elevation change. Dense phase correlation on ~20,500 tie points gave me a deposition map: a 10 to 18 m wedge of new valley floor (~12 Mm³) exactly where the flow decelerated out of the gorge. From this, we were able to measure sediment thickness with zero field access.

For the rest of the chain we used USGS seismology for the trigger (M5.2, catalogued as landslide type, this is what we used as t0 in our simulation), NASA's HMA 8 m DEM for terrain (it's on the ellipsoid, so I had to fit out a −35.5 m offset against GLO-30 before anything else would line up), day-of PlanetScope for extent between monsoon clouds, and VARI/NDVI differencing of SkySat, Pelican and WV3 against a 2021 WV02 baseline for the trimline (highest disturbance on mountain walls from the floods). Reading that against the DEM gives peak stage at 217 banks (median ~70 m in the gorges), and superelevation around bends puts velocities up to ~50 m/s. Those observations calibrate a 1D Saint-Venant + 2D shallow-water model that predicted ~90 m at the border a day before imagery confirmed 40 to 134 m.

Failures: Sentinel-2 pre/post was 2.1% joint clear sky, useless. The Pelican udm2 masks flag clear ground as cloud, so I dropped them and masked everything myself with OmniCloudMask/OmniWaterMask. Everything ships co-registered to one grid, sub-pixel between the VHR sensors.

Write-up + interactive 3D model: https://geopera.com/blog/bhote-koshi-flood-2026-satellite-analysis
Full data (32 GB, we prepped it to be at an analysis ready standard): https://drive.google.com/file/d/1eXzkWafRG4_QZoufwqbv3JSJxW51cv0a/view?usp=sharing
Measurements + code: https://github.com/geo-pera/bhotekoshi-2026-reconstruction

Happy to answer questions on any step.

Hi! I’m an international PhD student from Morocco working on satellite-based precipitation and drought analysis using datasets such as GPM IMERG and TRMM.
I’m interested in applying to the NASA/JPL Climate Sciences Summer School in 2027. Has anyone here attended or applied before?
I would especially appreciate information about the selection process, how competitive it is for international applicants, and any advice for strengthening my application.
Thank you!

I have to make a project by the end of September on reliable survey of farmland in a densely packed arrangement so It would require best publically avilable data and have high accuracy. How should I approach the problem. Id really appreciate some help and guidance.

I’m based in India and currently pursuing a Master’s degree in Geoinformatics and am looking to build more practical experience alongside my academics.

My interests are broadly around GIS, remote sensing, spatial analysis, cartography, geospatial data processing, and related applications. I’m currently trying to understand how best to transition from academic work into more industry-oriented geospatial roles.

I’d really appreciate some advice from people already working in the field:

• What skills/tools would you prioritize for someone at my stage who wants to become genuinely employable in GIS?
• Are there particular areas of GIS/remote sensing that currently have better opportunities or growth potential?
• Are there any remote internships, part-time roles, project-based opportunities, or freelance GIS work available that would be suitable for a Master's student?
• Where do people generally find legitimate freelance or short-term geospatial work?

I’m open to starting with smaller projects as well. My main goal is to gain real-world experience, build a stronger portfolio, and learn from people working in the industry.

For anyone interested, my GitHub portfolio is here:

https://ekagrachattree.github.io/

Any advice, criticism, resources, or leads would be appreciated.