BAIS2 (Burned Area Index for Sentinel 2)
//
// Burned Area Index for Sentinel-2 (abbrv. BAIS2)
// Based on DOI: 10.3390/ecrs-2-05177
// 2nd International Electronic Conference on Remote Sensing, Volume: Proceedings, 2(7), 364
// By Federico Filipponi of ISPRA
// URL https://www.researchgate.net/publication/323964124_BAIS2_Burned_Area_Index_for_Sentinel-2
// Adapted by Harel Dan. @hareldan, harel.dunn@gmail.com
//
let index = (1-((B06*B07*B8A)/B04)**0.5)*((B12-B8A)/((B12+B8A)**0.5)+1);
let min = 0;
let max = 0.99;
let zero = 0.5;
// colorBlend will return a color when the index is between min and max and white when it is less than min.
// To see black when it is more than max, uncomment the last line of colorBlend.
// The min/max values were computed automatically and may be poorly specified, feel free to change them to tweak the displayed range.
// This index crosses zero, so a diverging color map is used. To tweak the value of the break in the color map, change the variable 'zero'.
let underflow_color = [1, 1, 1];
let low_color = [0/255, 0/255, 255/255];
let high_color = [255/255, 20/255, 20/255];
let zero_color = [250/255, 255/255, 10/255];
let overflow_color = [255/255, 0/255, 255/255];
return colorBlend(index, [min, min, zero, max],
[
underflow_color,
low_color,
zero_color, // divergent step at zero
high_color,
overflow_color // uncomment to see overflows
]);Evaluate and Visualize
General description of the script
BAIS2 adapts the traditional BAI for Sentinel-2 bands, taking advantage of the wider spectrum of Visible, Red-Edge, NIR and SWIR bands.
Values description: The range of values for the BAIS2 is -1 to 1 for burn scars, and 1 - 6 for active fires. Different fire intensities may result in different thresholds, the current values were calibrates, as per original author, on mostly Mediterranen regions.
Description of representative images
Burned area index, Las Palmas de Grand Canaria. Acquired on 19.08.2019.
