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Sentinel-5P Formaldehyde - HCHO

var minVal = 0.0;
var maxVal = 0.001;
var diff = maxVal - minVal;
const map = [
	[minVal, 0x00007f], 
	[minVal + 0.125 * diff, 0x0000ff],
	[minVal + 0.375 * diff, 0x00ffff],
	[minVal + 0.625 * diff, 0xffff00],
	[minVal + 0.875 * diff, 0xff0000],
	[maxVal, 0x7f0000]

const visualizer = new ColorRampVisualizer(map)
function setup() {
   return {
    input: ["HCHO","dataMask"],
    output: { bands: 4 }

function evaluatePixel(samples) {
   const [r, g, b] = visualizer.process(samples.HCHO);
   return [r, g, b, samples.dataMask];

Evaluate and Visualize


Long term satellite observations of tropospheric formaldehyde (HCHO) are essential to support air quality and chemistry-climate related studies from the regional to the global scale. The seasonal and inter-annual variations of the formaldehyde distribution are principally related to temperature changes and fire events, but also to changes in anthropogenic (human-made) activities. Its lifetime being of the order of a few hours, HCHO concentrations in the boundary layer can be directly related to the release of short-lived hydrocarbons, which mostly cannot be observed directly from space. Measurements are in mol per square meter (mol/ m^2). Learn more here.

Description of representative images

High formaldehyde concentrations over Ghana, 2020-01-24. NO2 tropospheric column