no2 concentrations amid lockdown

Measured by sentinel-5

Nitrogen dioxide (NO2) and nitrogen oxide (NO) together are usually referred to as nitrogen oxides (NOx = NO + NO2). They are important trace gases in the Earth’s atmosphere, present in both the troposphere and the stratosphere. They enter the atmosphere as a result of anthropogenic activities (notably fossil fuel combustion and biomass burning) and natural processes (such as microbiological processes in soils, wildfires and lightning).

// get the data
var y2019 = ee.ImageCollection("COPERNICUS/S5P/OFFL/L3_NO2").filterDate("2019-02-01","2019-02-28");
var y2020 = ee.ImageCollection("COPERNICUS/S5P/OFFL/L3_NO2").filterDate("2020-02-01","2020-02-28");

// get the layer with all countries
var countries = ee.FeatureCollection("USDOS/LSIB_SIMPLE/2017").filter(ee.Filter.eq("country_co", "CH"))

// add layers to map
Map.addLayer(y2019.max().select("NO2_column_number_density").clip(countries),{min:0.00002,max:0.0005,palette:"lightblue,orange,yellow,red,purple"},"Feb 2019");
Map.addLayer(y2020.max().select("NO2_column_number_density").clip(countries),{min:0.00002,max:0.0005,palette:"lightblue,orange,yellow,red,purple"},"Feb 2020");

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