How to use free satellite data to monitor natural disasters and environmental changes

Rising availability of open-access information from authorities satellites have made it attainable for everybody to realize perception into environmental modifications underway

Over 8,000 satellites are orbiting Earth today, capturing images like this, of the Louisiana coast. Source: NASA Earth Observatory Over 8,000 satellites are orbiting Earth at present, capturing photographs like this, of the Louisiana coast. Supply: NASA Earth Observatory

If you wish to observe modifications within the Amazon rainforest, see the complete expanse of a hurricane or work out the place folks need assistance after a catastrophe, it’s a lot simpler to do with the view from a satellite tv for pc orbiting a few hundred miles above Earth.

Historically, entry to satellite tv for pc information has been restricted to researchers and professionals with experience in distant sensing and picture processing.

Nevertheless, the growing availability of open-access information from authorities satellites comparable to Landsat and Sentinel and free cloud-computing sources comparable to Amazon Web Services, Google Earth Engine and Microsoft Planetary Computer, have made it attainable for almost anybody to realize perception into environmental modifications underway.

I work with geospatial big data as a professor. Right here’s a fast tour of the place you could find satellite tv for pc photographs, plus some free, pretty easy instruments that anybody can use to create time-lapse animations from satellite tv for pc photographs.

For instance, state and concrete planners — or folks contemplating a brand new residence — can watch over time how rivers have moved, development crept into wildland areas or a coastline eroded.

A squiggly river moves surprisingly quickly over time.
Landsat time-lapse animations present the river dynamics in Pucallpa, Peru. Supply: Qiusheng Wu, NASA Landsat
Animation shows the shoreline shrinking.
A Landsat time-lapse reveals the shoreline retreat within the Parc Pure del Delta, Spain. Supply: Qiusheng Wu, NASA Landsat

Environmental teams can monitor deforestation, the results of local weather change on ecosystems, and the way different human actions like irrigation are shrinking bodies of water like Central Asia’s Aral Sea. And catastrophe managers, support teams, scientists and anybody can monitor pure disasters comparable to volcanic eruptions and wildfires.

The lake, created by damming the river, has shrunk over time.
GOES photographs present the decline of the essential Colorado River reservoir Lake Mead because the Nineteen Eighties and the expansion of neighboring Las Vegas. Supply: Qiusheng Wu, NOAA GOES
A volcanic eruption bursts into view.
A GOES satellite tv for pc time-lapse reveals the Hunga Tonga volcanic eruption on Jan. 15, 2022. Supply: Qiusheng Wu, NOAA GOES

Placing Landsat and Sentinel to work

There are over 8,000 satellites orbiting the Earth at present. You’ll be able to see a stay map of them at

Some transmit and obtain radio indicators for communications. Others present international positioning system (GPS) companies for navigation. Those we’re excited about are Earth commentary satellites, which gather photographs of the Earth, day and night time.

Landsat: The longest-running Earth satellite tv for pc mission, Landsat, has been amassing imagery of the Earth since 1972. The most recent satellite tv for pc within the collection, Landsat 9, was launched by NASA in September 2021.

On the whole, Landsat satellite tv for pc information has a spatial decision of about 100 ft (about 30 meters). For those who consider pixels on a zoomed-in photograph, every pixel can be 100 ft by 100 ft.

Landsat has a temporal decision of 16 days, which means the identical location on Earth is imaged roughly as soon as each 16 days. With each Landsat 8 and 9 in orbit, we will get a world protection of the Earth once every eight days. That makes comparisons simpler.

Landsat data has been freely obtainable to the general public since 2008. Throughout the Pakistan flood of 2022, scientists used Landsat information and free cloud-computing sources to find out the flood extent and estimated the total flooded area.

Images show how the flood covered about a third of Pakistan.
Landsat satellite tv for pc photographs displaying a side-by-side comparability of southern Pakistan in August 2021 (one yr earlier than the floods) and August 2022 (proper) Supply: Qiusheng Wu, NASA Landsat

Sentinel: Sentinel Earth commentary satellites have been launched by the European House Company (ESA) as a part of the Copernicus program. Sentinel-2 satellites have been amassing optical imagery of the Earth since 2015 at a spatial decision of 10 meters (33 ft) and a temporal decision of 10 days.

GOES: The photographs you’ll see most frequently in U.S. climate forecasting come from NOAA’s Geostationary Operational Environmental Satellites, or GOES.

They orbit above the equator on the same speed Earth rotates, to allow them to present steady monitoring of Earth’s environment and floor, giving detailed info on climate, local weather, and different environmental circumstances. GOES-16 and GOES-17 can picture the Earth at a spatial decision of about 1.2 miles (2 kilometers) and a temporal decision of 5 to 10 minutes.

Animation showing swirling clouds off the coast and the long river of moisture headed for California.
A GOES satellite tv for pc reveals an atmospheric river arriving on the West Coast in 2021. Picture: Qiusheng Wu, GOES

How one can create your individual visualizations

Up to now, making a Landsat time-lapse animation of a particular space required in depth information processing abilities and a number of other hours and even days of labor. Nevertheless, these days, free and user-friendly applications can be found to allow anybody to create animations with only a few clicks in an web browser.

As an illustration, I created an interactive web app for my college students that anybody can use to generate time-lapse animations rapidly. The person zooms in on the map to seek out an space of curiosity, then attracts a rectangle across the space to put it aside as a GeoJSON file — a file that comprises the geographic coordinates of the chosen area.

Then the person uploads the GeoJSON file to the online app, chooses the satellite tv for pc to view from and the dates and submits it. It takes the app about 60 seconds to then produce a time-lapse animation.

How one can create satellite tv for pc time-lapse animations.

There are a number of different helpful instruments for simply creating satellite tv for pc animations. Others to strive embrace Snazzy-EE-TS-GIF, an Earth Engine App for creating Landsat animations, and Planetary Computer Explorer, an explorer for looking out and visualizing satellite tv for pc imagery interactively.The Conversation

Qiusheng Wu, Assistant Professor of Geography and Sustainability, University of Tennessee

This text is republished from The Conversation below a Inventive Commons license. Learn the original article.


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