Thermal Escalation Methodology

How WorldMonitor clusters FIRMS/VIIRS thermal detections, compares them with local baselines, and assigns thermal escalation status and relevance.

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Weather satellites detect heat. Every day they log thousands of hot spots worldwide — most of them farmers burning stubble, flares at refineries, and ordinary wildfires. Buried in that noise are the ones that matter: a burning depot, a struck refinery, a fire that should not be there.

Thermal Escalation is the filter. It asks one question about every heat detection: is this unusual for this place?

How it decides something is unusual

Individual satellite pixels are first grouped into clusters — nearby detections seen around the same time are almost certainly one event, not fifteen. Each cluster is then compared against what that same patch of ground normally looks like, using the previous seven days as the yardstick.

A fire in a place that burns every week is normal. The same fire where nothing has burned in a month is not. That comparison is the entire idea.

Each cluster comes out with a status:

Status	What it means
spike	A sudden, sharp departure from the local baseline. Something just started.
persistent	Burning for 12+ hours and still above baseline. Something is sustained.
elevated	Above the local norm, but not dramatically.
normal	Consistent with what this area usually does.

Two more fields shape what reaches the top of the panel. Relevance is raised when a cluster is both unusual and in a region with active conflict — the combination that most often means infrastructure rather than agriculture. Confidence reports how much evidence stands behind the call: how many detections, how many separate satellites saw it, and how much baseline history exists to compare against.

Terminology. FRP (fire radiative power) is the measured energy output of a detection — roughly, how intensely it is burning, as opposed to how many pixels lit up. Both are used, because a small very hot event and a large smouldering one are different situations.

A detection is heat, not a cause. These satellites cannot distinguish a struck fuel depot from a crop burn. Everything here is a prompt to look, never a conclusion about what happened. The conflict-adjacency test is also a region-label match, not a live distance calculation against confirmed conflict events.

Thermal Escalation turns FIRMS/VIIRS hotspot detections into clustered, baseline-aware watch items for the thermal-escalation panel. The implementation lives in scripts/lib/thermal-escalation.mjs.

Clustering

Detections are sorted by observation time and grouped by region label. A detection joins the nearest existing cluster in the same region when it falls within 20km; otherwise it starts a new cluster. Cluster centroids are updated incrementally as detections are added.

Each cluster is assigned to a 0.5-degree baseline cell by rounding latitude and longitude to the nearest 0.5 degrees.

Baseline and Persistence

The scorer keeps 30 days of cell history and uses the last 7 days as the comparison baseline. For each cluster it computes:

Metric	Meaning
baselineExpectedCount	Average prior observation count in the cell
baselineExpectedFrp	Average prior total fire radiative power in the cell
countDelta	Current observation count minus baseline count
frpDelta	Current total FRP minus baseline FRP
zScore	Count delta divided by baseline count standard deviation
persistenceHours	Duration since the first current or recent prior observation

Prior observations within 18 hours extend persistence. The panel display window is 24 hours.

Status Rules

Status	Rule
persistent	persistenceHours >= 12 and either countDelta >= 3 or totalFrp >= 80
spike	zScore >= 2.5, countDelta >= 6, frpDelta >= 120, or observationCount >= 8 with totalFrp >= 150
elevated	zScore >= 1.5, countDelta >= 3, frpDelta >= 50, or no baseline with observationCount >= 5
normal	None of the above

Context and Relevance

Conflict adjacency is determined from the cluster’s region label, not from a live distance join against conflict events. The current conflict-region allowlist is:

Ukraine, Russia, Israel/Gaza, Syria, Iran, Taiwan, North Korea, Yemen, Myanmar, Sudan, South Sudan, Ethiopia, Somalia, Democratic Republic of the Congo, Libya, Mali, Burkina Faso, Niger, Iraq, and Pakistan.

Strategic relevance is assigned as:

Relevance	Rule
high	Conflict-adjacent and status is spike or persistent
medium	Status is persistent, total FRP is at least 120, or persistence is at least 12 hours
low	None of the above

The current implementation does not perform infrastructure-proximity matching. nearbyAssets is emitted as an empty array until an asset matcher is wired into the seeder.

Confidence

Confidence	Rule
high	At least 8 observations, at least 2 unique satellite sources, and at least 4 baseline samples
medium	At least 4 observations and at least 2 baseline samples
low	Anything below the medium threshold

Rows are sorted by relevance, then status severity, total FRP, and observation count.