How extreme temperatures impact EV sales
PLUS: quantifying the vertical growth of cities, detecting rare earth minerals from space, and more.
Hey guys, welcome to this week’s edition of the Spatial Edge — a weekly round-up of geospatial news that you can digest quicker than you can say ‘dihedral corner reflector scattering’. The aim is to make you a better geospatial data scientist in less than 5 minutes a week.
In today’s newsletter:
EV Adoption: How extreme temperatures and power outages impact uptake
Vertical Growth: Quantifying the growth of Asian and African cities vertically
Rare Earth Detection: Satellites find neodymium from space
Heat vulnerabilities: understanding how heatwaves impact vulnerable communities
Building datasets: measure annual changes in built-up areas and building height
Research you should know about
1. How extreme weather and power supply disruptions affect EV adoption
EVs. They’re almost as divisive as Marmite. And a new study examines how power supply disruptions affect electric vehicle (EV) adoption. The bottom line here is that unreliable electricity infrastructure seems to deter the shift towards EV uptake.
The researchers compiled high-resolution, geo-referenced data on power outages across 310 cities in China from November 2019 to September 2021 by scraping daily power failure reports from official city websites. They combined this with data on new EV registrations, using automobile insurance records as a proxy for sales figures. They then assessed how variations in power outages influenced EV adoption. To address potential causality issues, they used extreme temperature days as an instrumental variable—since extreme weather can cause outages but is unrelated to EV adoption decisions.
The study found that each additional power outage per district in a month led to a 0.99% decrease in new EVs adopted. Doubling the number of outages in one year could depress EV adoption rates for up to a decade, potentially reducing carbon reduction benefits by over $31.3 million per year. This is massive.
2. Assessing the extent to which cities are growing vertically
A new study published in Nature Cities demonstrates the extent to which Asian and African cities are (following the trend in Europe and America) shifting from spreading outwards to building upwards.
The team combined microwave backscatter data from three satellite scatterometers, covering the 1990s to the 2010s, with the World Settlement Footprint evolution dataset, which maps built-up areas over time. Microwave backscatter measures radar reflections from the Earth's surface and can indicate building heights due to reflections between building walls and the ground. By integrating these datasets, they were able to classify urban growth into four categories:
slow growth,
outward expansion,
upward growth, and
rapid 3D growth (both up and out).
The study found that from the 1990s to the 2010s, areas of outward urban growth decreased by 56%, while areas of upward growth increased by about 400%, and regions experiencing both types surged by roughly 570%. This shift was most pronounced in megacities and fast-developing cities in places like China.
We all know that cities in more developed regions are growing upwards. But I find it cool to be able to quantify the extent to which this is happening in Asia and Africa using EO data.
3. Detecting rare earth minerals from hyperspectral satellite data
A new study published in Scientific Reports demonstrates how EnMAP hyperspectral satellite data can detect rare earth elements in geological environments. Researchers focused on Mountain Pass, California, successfully identifying neodymium—an essential rare earth element—using satellite images for the first time.
The team analysed EnMAP satellite data, which provides high-res hyperspectral images across a bunch of different wavelengths. They were able to characterise the distinct absorption features of neodymium around 740 and 800 nm. This then allowed them to map neodymium at a 30m resolution over known bastnaesite ore deposits in the area.
In addition, hundreds of other pixels indicating neodymium presence were identified and validated through laboratory spectroscopy and geological data.
The takeaway here is that hyperspectral satellite data can provide a fast and cost-effective method for screening large areas for rare earth elements.
4. Understanding how heatwaves impact vulnerable communities
A new study in Scientific Reports examines how heatwave exposure impacts historically vulnerable communities in Mississippi. It’s focussed on the increasing frequency and duration of heatwaves and their effects on more disadvantaged areas.
The paper uses hourly temperature data from ground-based weather stations and the ERA5 reanalysis dataset. They calculated a bunch of heatwave metrics—including frequency, duration, and intensity. They also integrated these with the Social Vulnerability Index from the CDC (which includes factors like income, age, and race) to develop an integrated ‘Heatwave Risk Index’.
They found a significant increase in heatwave frequency and duration across all counties, especially in prolonged events without overnight relief. Northwest Mississippi emerged as a hotspot with high heat exposure and elevated social vulnerability.
All in all it’s an interesting tool that can help us identify which areas need more targeted support to address heat exposure. These findings align with another paper I previously discussed on the inequalities of heat exposure.
Geospatial datasets
1. Open Buildings 2.5D temporal dataset
The 2.5D Building Evolution Dataset is a new dataset that provide annual info on building presence, building centroids, and building heights from 2016-2023. It’s available across Africa, Asia, Latin America and the Caribbean.
2. Forest Carbon Monitoring dataset
Planet has launched a Forest Carbon Monitoring product—the world's first global-scale system at a 3-meter resolution. This essentially estimates carbon stored in forests worldwide.
3. Wheat grain protein content dataset
I only learned after seeing this that wheat grains have a protein content of ~10%. And if you’re into wheat protein you’re in luck. The CNWheatGPC-500 dataset provides detailed information on wheat grain protein content (GPC) across major wheat-growing regions in China. It’s available at a 500-meter resolution
You can access the scripts via Zenodo.
4. Individual tree detection dataset
A new study from Scientific Reports introduces an open-access dataset for developing, evaluating, and comparing individual tree detection algorithms in dense mixed forests. The researchers collected data on 3,600 trees from ten plots, using UAV LiDAR for detailed 3D information and RGB images for high-resolution visual data.
The dataset is available on Kaggle, along with Python notebooks for data visualization and algorithm examples.
Other useful bits
Planet shared the first images from Tanager-1, their new hyperspectral satellite. The images capture Karachi, Pakistan, on 19 September, using 420 spectral bands.
This video tutorial from Open Geospatial Solutions shows how to rapidly install commonly used geospatial Python packages using the UV package manager. You can access the UV package here.
Google, in collaboration with WorldPop, has released updated versions of their Open Buildings dataset. It features building presence, centroids, and heights from 2016 to 2023.
Pangaea was recently launched, a new GitHub benchmark for geospatial models, focusing on dense tasks. It offers a unified codebase to test models on a diverse set of global datasets, from agriculture to disaster mapping, using various types of imagery. Pangaea is easy to extend, so anyone can contribute models or datasets.
Jobs
The World Bank is looking for a Data Scientist to join their Data Lab and Development Data Partnership team.
Hummingbirds is looking for a Remote Sensing Intern based in Paris, France who will support their Nature-based Solutions portfolio development.
ESA is looking for an Earth Observation Digital Innovation Engineer based in Frascati, Italy who will work within their ESA ɸ-lab.
The European Space Policy Institute (ESPI) is looking for a Research Fellow based in Vienna, Austria, particularly those with experience in green transition and climate policies applied to space.
GAF AG is looking for a Technical Project Manager based in Germany for Earth Observation Processing Chains and Data Analytics.
Google Deep Mind is looking for a Research Engineer under their Geospatial AI team.
The UN Office of Legal Affairs is looking for a Geospatial Information Assistant under their Division for Ocean Affairs and the Law of the Sea.
The Swiss Federal Institute of Technology in Lausanne has a PhD position open for Nightlights image analysis for humanitarian applications.
Just for fun
NASA’s Earth Observatory shared some stunning images of Earth’s seasons from geostationary orbit. The images show the Terminator (great name, I know) —the line between night and day—at different times of the year. You can even see cloud bands moving with the Sun’s position.
That’s it for this week.
I’m always keen to hear from you, so please let me know if you have:
new geospatial datasets
newly published papers
geospatial job opportunities
and I’ll do my best to showcase them here.
Yohan