Hannah Ker
hannah.ker@un.org

Data Request Number: 843
Longitude: -76.0
Latitude: 18.0
Earliest date: 2025-10-26
Latest date: 2025-11-15
Maximum percent cloud cover for flood scene: 10.0
Number of flood scenes requested: 1
Products requested:   water extent change map,
Target date for reference scene: 2025-10-01
maximum percent cloud cover for reference scene: 10.0
Planetscope data quality requested: standard


Processing History
Flood scene request results: data activation initiated successfully
Reference scene request results: data successfully identified
Cloud cover for the flood scene: 10


Processing History
Reference scene request results: data acquisition processed successfully
Flood scene request results: data processed successfully
Reference scene request results: request processed successfully
NDWI = 0.040009002130169266found for NDWI threshold
NDWI = -0.12553154665583804found for NDWI threshold
Water extent change map request results: request processed successfully
Request successfully completed
Time to process: 0:18:56.108909


Product descriptions
The following products are derived from Planetscope satellite data licensed to NASA by Planet Labs, Inc.
* Products that start with “flood_scene” are intended to be derived from data acquired during flood conditions.
* Products that start with “reference_scene” are intended to be derived from data acquired during reference conditions. Frequently, the system user will choose a date for reference scenes that corresponds to non-flood conditions.
* Products that start with “water_extent_change” map the water extent changes between the flood_scene products and the reference_scene products.
* Products that include “NDWI_map” (Normalized Differential Water Index) in the name are produced using the equation NDWI = (green_SR – NIR_SR)/ (green_SR + NIR_SR), where SR indicates surface reflectance and NIR is Near Infrared EM radiation.
* Products that include “NDVI_map” (Normalized Differential Vegetation Index) in the name are produced using the equation NDVI = (NIR_SR – red_SR)/ ( NIR_SR + red_SR).
* Products that include “nrg_image” in the name are false color composite images using the NIR, red, and green bands - displayed respectively as red, green, and blue. The images have been histogram stretched for improved visualization, and scaled by a random factor between 0.95 and 1.05 such that the original surface reflectance data cannot be retrieved.
* Products that include “water_map” in the name are maps of water derived using an NDWI dynamic thresholding approach (publication pending)
* The numerical strings in the product names are the Planet Labs, Inc. designations for the Planetscope surface reflectance data from which the products were derived.  The 1st numerical string in the product name is the acquisition date in the form YYYYMMDD.  The 2nd numerical string is the acquisition time (in UTC) in the form HHMMSS. The significance of the remainder of the Planetscope product names is not clear, excepting that the “.tif” extension indicates that the file is in GeoTIFF format.
* Note that the water extent change products are named from the flood_scene product used in the product. The reference_scene product name used to derive this product is included in the product metadata.


Legend for water maps:  
     0 = no data (suggested color => white or transparent)
     1 = clouds, bad pixels, etc (suggested color => gray)
     2 = not water (suggested color => green or tan)
     3 = water (suggested color => blue)
Legend for water extent change maps:  
     0 = no data (suggested color => white or transparent)
     1 = clouds, bad pixels, etc (suggested color => gray)
     2 = not water (suggested color => green or tan)
     3 = water coincident with reference map water, likely not flood (suggested color => blue)
     4 = water not coincident with reference map water, likely flood (suggested color => red)
     5 = water in flood scene, reference scene is unclear (suggested color => magenta)