5 satellite data types to improve wildfire risk models in 2026

And neither may be suitable for assessing whether individual buildings have been damaged. That distinction matters.

As Dave Fox, Co-founder and Chairman of Geospatial Insight, explains:

“There isn’t one satellite that does everything. The right data depends on what you’re trying to establish: where the fire is, how it is developing, what has burnt, or what has actually been damaged.”

Combining different satellite sources is therefore the smart answer.

Here are five of the most useful types of satellite data and where each fits.

1. VIIRS: detecting and monitoring active fires

One of the principal sources we use for FireWatch is VIIRS (Visible Infrared Imaging Radiometer Suite).

VIIRS sensors fly aboard the Suomi NPP, NOAA-20 and NOAA-21 satellites. They combine visible and infrared observations, including thermal bands that can identify temperature anomalies associated with wildfire.

The data provides fire observations at approximately 375-metre resolution. That may sound relatively coarse compared with modern commercial satellite imagery. But resolution is only one part of the equation. For active wildfire monitoring, frequency matters enormously.

Combined with MODIS data, VIIRS lets you map fire locations and extents about four times each day. The source data is also freely available.

“For finding and following active fires, you don’t necessarily need the highest-resolution image available. Frequency, coverage and cost can be much more important.”

2. MODIS: proven, frequent fire detection

MODIS (Moderate Resolution Imaging Spectroradiometer) flies aboard NASA’s Terra and Aqua satellites.

It detects fires using mid- and thermal-infrared wavelengths, with fire products produced at approximately 1km resolution.

MODIS is old technology by satellite-industry standards. Terra was launched in 1999, and Aqua in 2002, and both satellites are now approaching the end of their operational lives.

Yet that shouldn’t obscure how useful the data has been. The interesting lesson is that the newest or highest-resolution satellite isn’t automatically the most operationally useful.

“There is a tendency to assume newer and higher resolution must mean better. For wildfire detection, that isn’t necessarily true. MODIS and VIIRS give us frequent observations across enormous areas, and the underlying data is free.”

3. Sentinel-2 and PlanetScope: mapping what actually burned

Once a fire has passed, the question changes. Instead of asking “Where is the fire now?”, we may want to know “What actually burned?”

For that, higher-resolution multispectral imagery becomes valuable.

The European Copernicus Sentinel-2 satellites collect imagery across 13 spectral bands. They include visible, near-infrared and short-wave infrared data, with some imagery available at 10m resolution.

At UK latitudes, the operational Sentinel-2 satellites can typically provide observations every two to three days, subject, of course, to cloud and smoke.

That information can be used for burn-scar mapping.

We are also looking at PlanetScope imagery for this purpose. Planet operates roughly 200 PlanetScope satellites, allowing locations to be imaged multiple times a day, conditions permitting.

PlanetScope provides imagery at approximately 3m resolution, offering considerably more detail than freely available sources.

“Once the fire has passed, we’re solving a different problem. We no longer just want to know where thermal activity was detected. We want to map the area that actually burned.”

4. Radar: seeing through cloud and smoke

Optical satellites have an obvious problem during natural catastrophes. They need to see the ground. Cloud and smoke can therefore make otherwise excellent imagery unusable.

Radar satellites offer another option because radar can penetrate cloud and smoke.

Sentinel-1, for example, can provide imagery at around 20m resolution, while commercial radar providers can achieve much finer resolutions.

That makes radar potentially useful for post-fire mapping when atmospheric conditions prevent conventional optical imagery from getting a clear view.

There is a trade-off, however. Higher-resolution commercial satellite imagery can become expensive very quickly.

5. Very high-resolution imagery: understanding property damage

If the objective is to determine whether individual buildings have been damaged, 10m, 20m or 375m imagery isn’t enough. We then move into very high-resolution satellite imagery.

Sources can include Airbus Pleiades and Pleiades Neo, Vantor WorldView and Satellogic, giving imagery at approximately 30–50cm resolution.

Unlike satellites which predominantly capture imagery directly below them, these systems can often be tasked and pointed towards an affected area. That means daily revisits may be possible.

The disadvantage is straightforward: it costs money.

“If the question is whether an individual property has been damaged, we’re into a completely different level of imagery. That’s where very high-resolution satellites, or sometimes drones, become necessary.”

Why more resolution isn’t always the answer

One misconception in satellite intelligence is that higher resolution automatically means better information. It doesn’t.

For wildfire monitoring, the right question is:

Better for what?

If we need to find active fires across a very large area several times a day, freely available VIIRS and MODIS data may be more useful than expensive imagery at centimetre-level resolution.

If we’re mapping the precise burn scar afterwards, Sentinel-2 or PlanetScope may be preferable.

And if we’re assessing individual buildings, we may need very high-resolution tasked imagery.

“I’d always come back to the purpose. The best resolution you can buy isn’t necessarily the best data for the job. Sometimes a coarse image arriving several times a day is far more valuable than a beautiful high-resolution image arriving too late.”

There is another important issue. The raw fire data from sources such as VIIRS and MODIS is publicly available. The value isn’t simply obtaining it.

A significant part of our work is removing false positives and turning repeated observations into a consistent historic record of fires. That historic archive can then become valuable in its own right.

What about the new generation of thermal satellites?

A new generation of thermal infrared satellites is emerging. These include missions from companies such as SatVu, Constellr and OroraTech.

They are technically interesting and may introduce new capabilities. But we should be careful not to assume that a new satellite automatically solves the wildfire-monitoring problem better.

Dave is deliberately cautious about some of the excitement surrounding the technology:

“I’m not convinced yet that new thermal satellites automatically transform wildfire monitoring. Low-resolution, high-frequency data such as VIIRS and MODIS already does an extremely useful job of detecting and monitoring fires – and crucially, the data is free.”

The future of wildfire intelligence probably isn’t one perfect satellite. It’s using the right satellite, at the right resolution, at the right point in the event.

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Photo by USGS