Dear Uilson,

If you would like to extract point data you can use the e=services provided by ORNL-DAAC for MODIS product (e.g. MOD16A2). If you want to develop your own code, you may also contact them. I have been in touch with them and they are very friendly and supported team. This is the website https://modis.ornl.gov/data.html

Good luck!

Thank you all for the answer!

Dear Islam,

For calculating annual AET from MOD16A2 product, you can use below code:

var imageCollection = ee.ImageCollection("MODIS/NTSG/MOD16A2/105"), MOD16 = ee.ImageCollection("MODIS/006/MOD16A2"), IRAN = ee.FeatureCollection("users/javadian/IRAN");

var startYear = 2001;

var endYear = 2018;

var startDate=ee.Date.fromYMD(startYear,01,01);

var endDate=ee.Date.fromYMD(endYear+1,12,31);

//SDA

var StudyArea = IRAN;

//ET filtered based on dates and study area (IRAN)

var ET = MOD16.filterDate(startDate, endDate)

.select(['ET']);

//ANALYSIS: Annual Averages

var year_list = ee.List.sequence(startYear, endYear);

var ET_ym = ee.ImageCollection.fromImages(year_list.map(function (ynz)

{

var img = ET.filter(ee.Filter.calendarRange(ynz, ynz, 'year'))

.sum();

return img.set('year', ynz)

.set('month', 1)

.set('date', ee.Date.fromYMD(ynz,1,1))

.set('system:time_start',ee.Date.fromYMD(ynz,1,1));

}).flatten());

print(ET_ym);

//CHART

var ET_chart = ui.Chart.image.series({imageCollection: ET_ym,

region: StudyArea,

reducer: ee.Reducer.mean(),

scale: 1000

})

.setOptions({title: "ET MEAN",

pointSize: 3});

print(ET_chart);

Dear Mostafa Javadian

would you modify the code for monthly analysis

thanks in advance

Dear Mostafa Javadian, how are you?

The code really works, thank you! Could you add to the script the code that restricts the Xingu River Basin - Brazil? I tried to limit the calculation of Evapotranspiration in such a Basin but I couldn't get it with your code ... Please!

Sarah Ribeirp

Hi Sarah,

You just need to import your region of study. Then, you can easily define it as the main region for the calculations.

Best,

Mostafa

Mostafa Javadian Would you have an example of how to filter a particular study area using the code you created? I'm learning to work with GHG, and I'm not managing to filter the Xingu River Basin :( Please !!!

Dear Sarah Ribeirp ,

just upload a shapefile of the Xingu River Basin from your computer according to this tutorial: https://thegeoict.com/blog/2019/08/05/uploading-a-shapefile-to-google-earth-engine/ , then add it to the code, and in the definition of the StudyArea variable change "IRAN" to the name of your variable, as you named it after importing into the code (point 6 in the tutorial).

Regards,

Daniel

Hi, I'm having trouble designing the 2001-2021 code. i need help!