Is it getting hot in here? let’s check with the GEE!
The MODIS product mod11 contains a band with information on data surface temperature. Use the script below to check whether it really is getting hotter.
// Specify name of country. var country_names = ['Vietnam']; // get fusion table with countries var countries = ee.FeatureCollection('ft:1tdSwUL7MVpOauSgRzqVTOwdfy17KDbw-1d9omPw'); // select the country from the fusion table var vietnamCountry = countries.filter(ee.Filter.inList('Country', country_names)).geometry(); // set start date var startdate = ee.Date.fromYMD(2000,1,1); // set end date var enddate = ee.Date.fromYMD(2016,12,31); // filter the data collection var temp = mod11.filterDate(startdate, enddate) .sort('system:time_start', false) .filterBounds(vietnamCountry) .select("LST_Day_1km") // convert LST to celcius var toCelsius = function(image){ var time = image.get('system:time_start') var celsius = image.multiply(0.02) // scale factor .subtract(273.15) // from kelvin to C .rename("Celcius") .set('system:time_start',time) return celsius; }; var CollectioninCelsius = temp.map(toCelsius) var viz = {min:20.0, max:34, palette:"000b5e,96048f,4286f4,e2f442,960424"}; Map.addLayer(CollectioninCelsius.median().clip(vietnamCountry),viz,"temperature map") Map.centerObject(vietnamCountry,5) // Predefine the chart titles. var title = { title: 'Temperature over time', hAxis: {title: 'Time'}, vAxis: {title: 'Temperature (C)'}, }; // create the chart var tempchart = ui.Chart.image.seriesByRegion(CollectioninCelsius, vietnamCountry, ee.Reducer.mean(), 'Celcius', 1000, 'system:time_start', 'PROJECT').setOptions(title); // print the chart print(tempchart);
See the full example here.
hi! This guide is very helpful now that I’m taking up a Remote Sensing class in school and we’re exploring Google Earth Engine! May I know where can I get the data uploaded on your fusion table? Thank you very much!
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This (https://mygeoblog.com/2016/10/17/creating-fusion-tables/) post shows you how to upload a fusion table.
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Hello,
how do I import the variable “mod11”?
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var mod11 = ee.ImageCollection(“MODIS/MOD11A2”)
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Thank you so much!! 😀
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Hi, how can i get the information of average temperature out of the console tab??
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copy – paste.. or write the data to a csv file.
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Thank you so much, it works!
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I would like to know how to filter by specific date and time, in this case 10 am (Chile) and for modis LST 1KM images daily. I do not know how to put the time in a script.
regards
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use the .filterDate(startdate, enddate)
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Hello,
When calculating temperature, is it recommended to mask out the clouds and cirrus as described in one of your other turorials?
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