AI for good

An illustration of an urban heat island.

NASA/JPL-Caltech

Jasna Budhathoki and Jenish Budhathoki, a sister-brother team, have completed an award-winning AI / machine learning project that promises to save lives. The Heat-Sccape: Mapping Urban Heat from Space project uses satellite imagery to measure land surface temperatures at the neighborhood level and identify urban areas most vulnerable to extreme heat. It combines physics-based modeling with machine learning.

The need

There are up to 12,000 heat-related deaths each year in the U.S. alone. In most counties communities of color experience significantly higher surface temperatures than white, wealthier neighborhoods. Those areas can be up to 7 ℉ warmer.

Heat-Sccape uses high-resolution land surface temperature (LST) maps to identify the hottest neighborhoods. Those are overlaid with income and demographic data. This enables directing cooling resources to areas with the greatest need. Those resources could include urban greening, cool roofs, or hydration stations.

In terms of climate resilience, the project can track surface temperature trends, measure whether mitigation investments are working, and forecast heat risk. Results can be available within minutes of satellite overpass, leading to alerts when heat thresholds are exceeded, with risk summaries downlinked directly to city systems.

See more about the project including technical details.

Work on the project (from Jenish)

In the qualifying round, we used a neural network to process satellite images and mark every pixel that was a building or paved surface. We trained the network on 27,000 labeled images, letting it guess, measure how wrong it was, and adjust itself millions of times.

Our final round task was to turn a satellite’s raw heat readings into ground temperatures, accurate to about a degree. There were two main issues we encountered for this task: first, the heat signal has to cross the whole atmosphere to reach the satellite, and water vapour absorbs some of it in transit, so every surface reads colder than it really is. And second, materials differ in how efficiently they emit heat. A metal roof and a patch of grass at exactly the same temperature send out different amounts of infrared, so the satellite reads them as different temperatures when they are not. We corrected the first using the fact that water vapour interferes unevenly across wavelengths, so the difference between two detectors reveals how much interference there was, and the second by looking up NASA’s measured emissivity at each exact coordinate. Because we only had 574 labelled examples which is not enough for a large model, we used physics for retrieval and used a small machine learning model to remove the leftover error. That finished ninth internationally with a bronze medal.

Bronze award

The team won a Bronze Medal at the AI and Space Computing Challenge 2026, a global competition held under the United Nations’ “AI for Good” initiative, placing seventh worldwide in the “Space Intelligence for Resilient Cities” track. Jenish led the team through both rounds, from the initial proposal to the final submission, The team is now expanding the project to many other US cities.

From a MyRepublica article:

“I had already spent a lot of time working with climate data at Duke, so when I came across this challenge, I knew exactly what kind of problem I wanted to solve,” Jenish said. “Leading a team was intimidating at first, but once we had a clear plan, it became more about doing the work. I learned as much from this project as I have from any class.”

Jasna said the project involved “a lot of late nights” alongside her work but was especially rewarding because she got to build something with her brother and watch him lead the project.

The team completed the project, shortly after Jenish graduated from high school and before starting college at Macalester. During his gap year, he gained research experience working with climate datasets at Duke University. Jasna developed the machine-learning model used to refine the team’s temperature predictions. She is a software development engineer at Amazon with a recent MS in Computer Science with a specialization in Machine Learning from Columbia University.

Bring on the flood

Imja Tsho

Imja Tsho

Today’s BBC News reports on an important development in Nepal, one which should be a warning to us all (Nepal drains dangerous Everest lake).

Nepal’s army has just completed lowering Lake Imja by 10 ft. This is because it was in danger of flooding downstream settlements with over 50,000 people.

Lake Imja, near Mount Everest (Sagarmatha) at 16,400 ft altitude, is one of thousands of such glacial lakes in the Himalayas. Many of the lakes are filling fast because of accelerated melting of glaciers due to rising temperatures.

The Himalaya region has been described as the third pole of the earth. It is melting, just as the Arctic and Antarctic are.

Lake Imja is a good example of that melting. It is a new lake, composed of glacial meltwater blocked by a terminal moraine. In 1962, it was 7.5 acres, and is now over 260.

I can only guess at the enormous cost of the six-month project, not just in dollars, but in terms of using up limited Nepali resources. It has been necessary to save lives, but sherpas in the region say there are many more lakes that endanger communities.

Embracing vInes

Celastrus orbiculatus (Oriental bittersweet)

Celastrus orbiculatus (Oriental bittersweet)

When Celastrus orbiculatus grows by itself, it forms thickets; when it is near a tree or shrub, the vines twist themselves around the trunk. The encircling vines have been known to strangle the host tree to death … All parts of the plant are poisonous. –Wikipedia, Celastrus orbiculatus

Oriental bittersweet continues to spread on Cape Cod, along with poison ivy, Virginia creeper, and English ivy. We now have kudzu, which used to be primarily in the American South.

Climate change is making poison ivy grow faster, bigger and meaner. Rising atmospheric levels of carbon dioxide and higher temperatures are to poison ivy what garbage is for rats, dormant water is for mosquitoes and road kill is to buzzards. –Templeton (2013)

Vines are spreading everywhere–lianas in Panama and air potato in Texas, which grows 8 inches a day. New York is releasing thousands of harmful Asian weevils as the only way to combat the relentless mile-a-minute vine. It’s happening all over the planet. Whether we like it or not, vines are embracing us, our walls and fences, and our trees.

Dioscorea bulbifera (air potato)

Dioscorea bulbifera (air potato)

Vines are increasing in many places because of forest fragmentation and habitat destruction. They’re also benefitting globally from increased CO2 in the atmosphere and global warming. Since they sequester less carbon than the trees they replace do, they then contribute to the growth of CO2. It’s a vicious cycle. Trees, but also ferns and other plants are at risk.

If you’ve ever walked through the jungle, you’ll know it can be surprisingly dark down on the forest floor. You see trees soaring up all around. You’re creating a dense canopy overhead. And climbing toward that canopy, snaking up the trees are the vines.

Now it may seem peaceful in there, but what you’re witnessing in very slow motion is a fight to the death: a fight between the trees and their old rivals, the vines. It’s a battle as old as the forests themselves. Now, scientists say the vines are winning. –Science Friday, NPR

Toxicodendron radicans, poison ivy

Toxicodendron radicans, poison

Vines can be quite beautiful. Grape vineyards have developed on the Cape, to what I’d consider to be a good end. Bougainvillea, Campsis (trumpet vine), Wisteria can be beautiful. Lathyrus odoratus (sweet pea) and Passiflora edulis (passionfruit) have delicious fruits. Even poison ivy provides forage for many animals and the fruits are popular with birds (who help spread it around).

Vines aren’t all bad, Maybe we should embrace them back.

But we may have to say good bye to the trees. And they were nice to have around, too.

References