Hotspots

A hotspot represents a thermal anomaly detected in satellite imagery. It is characterized by:

a unique identifier
the geographical coordinates
the ground sampling distance (GSD)
the detecting satellite
the acquisition time of the satellite image
fire radiative power (FRP)

Search

To search for hotspots the main endpoint to use is:

GET /v1/hotspots/

The endpoint searches for hotspots within a passed bounding box and filters results based on other parameters (a time range, advanced filters etc.).

Bounding box

When searching, a bounding box needs to be specified:

xmin, the minimum longitude
ymin, the minimum latitude
xmax, the maximum longitude
ymax, the maximum latitude

Date range

Time filters are passed to the API as date and minutes parameters, where:

date is the end date
minutes is the range before the end date, expressed in minutes

For example date=2024-01-15T00:00:00Z and minutes=2880 translates to the following time range:

Jan 14th 2024 00:00 UTC - Jan 15th 2024 00:00 UTC

The following date formats are supported for requests:

ISO8601 (e.g. YYYY-MM-DDTHH:mm:ssZ)
YYYY-MM-DD-HHmm, where HHmm is the time expressed in UTC

EPSG

The supported EPSG codes are:

4326 (WGS 84)
3857 (Web Mercator)

The epsg parameter defines the coordinate reference system of the bounding box and the feature geometries in the response. The default value is 4326.

Bounding box CRS

The bounding box coordinates are interpreted according to the specified EPSG code. If the bounding box is passed in a different CRS, the results may be incorrect.

Confidence

The confidence parameter allows to filter out hotspots with a lower level of algorithmic confidence. The parameter accepts a value between 0.0 and 1.0, where 0.0 is the lowest confidence and 1.0 is the highest confidence.

Hotspot confidence

Hotspot confidence doesn't represent the certainty of a fire, but the confidence of the algorithm in detecting a thermal anomaly. A low confidence value doesn't necessarily mean that the detected hotspot is not a fire.

Satellites

Allows to include only detections by the specified satellites. This parameter is advanced and only recommended, if specific satellites do not deliver reliable information for the area of interest.

Algorithms

Allows to include only detections by the specified detection algorithms. This parameter is advanced and only recommended, if specific algorithms do not deliver reliable information.

Select

The select parameter allows to include additional information in the response. The supported values are:

acquisition_time: the timestamp of the satellite acquisition for that hotspot
oldest_detection: the timestamp of the detection by an algorithm for that hotspot
satellite_product_filename: the filename of the satellite product that contains the hotspot. This may be useful for retrieving the original satellite image
normalized_frp: the normalized fire radiative power (FRP) of the hotspot

Multiple select values can be passed as a comma-separated list. See below for a full example.

All the selected values are included in the response as properties of the respective GeoJSON features.

GeoJSON Feature Collection

The server responds wiht a GeoJSON feature collection payload, containing a list of features, where each feature represents a single hotspot.

The geometry of each feature is always a Point.

Empty response

If no hotspots were found for the specified parameters, the response will be an empty feature collection.

The following properties are always included for every returned feature:

id: the unique identifier of the hotspot
frp: the fire radiative power expressed in MW
gsd: the ground sampling distance expressed in meters
satellite_name: the name of the satellite that detected this hotspot
satellite_orbit_type the orbit type of the satellite that detected this hotspot, may be LEO or GEO

Additional properties are included based on the passed select parameter.

Examples

Latest hotspots

To search for the most recent hotspots in a specific region:

curl -X GET \
    --url 'https://app.ororatech.com/v1/hotspots/?xmin=-120.66710&ymin=36.80301&xmax=-119.07488&ymax=37.77011&minutes=1440' \
    --header 'apikey: <my-api-key>'

The above request will yield all hotspots within the specified bounding box that were detected within the last 24 hours.

{
	"features": [
		{
			"type": "Feature",
			"geometry": {
				"type": "Point",
				"coordinates": [
					-120.64901,
					37.407589
				]
			},
			"properties": {
				"frp": 2.299654483795166,
				"gsd": 375,
				"id": 528254211,
				"satellite_name": "NOAA-20",
				"satellite_orbit_type": "LEO"
			}
		},
		{
			"type": "Feature",
			"geometry": {
				"type": "Point",
				"coordinates": [
					-119.7463,
					37.374413
				]
			},
			"properties": {
				"frp": 1.8877211809158325,
				"gsd": 375,
				"id": 527344664,
				"satellite_name": "SUOMI-NPP",
				"satellite_orbit_type": "LEO"
			}
		}
	],
	"type": "FeatureCollection"
}

Historical data

To search for older hotspots within a specific region:

curl -X GET \
    --url 'https://app.ororatech.com/v1/hotspots/?xmin=-120.66710&ymin=36.80301&xmax=-119.07488&ymax=37.77011&date=2024-02-22T00:00:00Z&minutes=1440' \
    --header 'apikey: <my-api-key>'

The above request will yield all hotspots within the specified bounding box that were detected between the dates 2024-02-21T00:00:00Z and 2024-02-22T00:00:00Z:

{
	"features": [
		{
			"type": "Feature",
			"geometry": {
				"type": "Point",
				"coordinates": [
					-120.04026,
					37.475243
				]
			},
			"properties": {
				"acquisition_time": "2024-02-21T21:23:55Z",
				"detection_time": "2024-02-21T21:53:22Z",
				"frp": 1.427635669708252,
				"gsd": 375,
				"id": 526607688,
				"satellite_name": "SUOMI-NPP",
				"satellite_orbit_type": "LEO"
			}
		},
		{
			"type": "Feature",
			"geometry": {
				"type": "Point",
				"coordinates": [
					-120.040916,
					37.475788
				]
			},
			"properties": {
				"acquisition_time": "2024-02-21T20:33:31Z",
				"detection_time": "2024-02-21T21:03:18Z",
				"frp": 2.498812437057495,
				"gsd": 375,
				"id": 526596161,
				"satellite_name": "NOAA-20",
				"satellite_orbit_type": "LEO"
			}
		}
	],
	"type": "FeatureCollection"
}

Advanced filtering

To search for hotspots with very specific filters, additional parameters can be set:

curl -X GET \
    --url 'https://app.ororatech.com/v1/hotspots/?xmin=-120.66710&ymin=36.80301&xmax=-119.07488&ymax=37.77011&date=2024-02-22T00:00:00Z&minutes=1440&satellites=NOAA-20' \
    --header 'apikey: <my-api-key>'

The above request will yield all hotspots within the specified bounding box that were detected by the NOAA-20 satellite between the dates 2024-02-21T00:00:00Z and 2024-02-22T00:00:00Z.

Hotspot details

The guide described how to search for many hotspots with a spatial and temporal filter. For more detailed information about a specific hotspot, refer to the GET /v1/hotspots/:id endpoint. Additional details may include:

detecting algorithm
satellite product information
associated fire clusters
additional physical properties

Best practices

GSD

The ground sampling distance (GSD) is an important parameter to consider when analyzing hotspots. The GSD represents the pixel size of the satellite sensor. The smaller the GSD, the more accurate the detection.

For example, a GSD of 375 meters means that any hotspot detected within such a pixel has an accuracy of approximately 375 meters.

Hotspot rendering

On the platform, hotspots are rendered as circles with a radius of half the GSD. This means that the actual detection area of a hotspot is a circle with a diameter equal to the GSD.

Time context

Hotspots have a specific timestamp and represent a snapshot of the detected thermal anomaly at that time. When analyzing hotspots, it is important to consider surroundings and successive hotspots to understand the fire's evolution.

Search​

Bounding box​

Date range​

EPSG​

Confidence​

Satellites​

Algorithms​

Select​

GeoJSON Feature Collection​

Examples​

Latest hotspots​

Historical data​

Advanced filtering​

Hotspot details​

Best practices​

GSD​

Time context​