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58d05081
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Adam M. Wilson
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## Example script that downloads data from Google Earth Engine using the python API
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## MODIS MOD09GA data is processed to extract the MOD09 cloud flag and calculate monthly cloud frequency
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## import some libraries
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import ee
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from ee import mapclient
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import ee.mapclient
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import datetime
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import wget
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import os
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#import logging
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#logging.basicConfig()
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## set working directory (where files will be downloaded)
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os.chdir('/home/adamw/acrobates/adamw/projects/cloud/data/mod09')
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#MY_SERVICE_ACCOUNT = '511722844190@developer.gserviceaccount.com' # replace with your service account
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#MY_PRIVATE_KEY_FILE = '/home/adamw/EarthEngine-privatekey.p12' # replace with you private key file path
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MY_SERVICE_ACCOUNT = '205878743334-4mrtqgu0n5rnsv1vanrvv6atqk6vu8am@developer.gserviceaccount.com'
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MY_PRIVATE_KEY_FILE = '/home/adamw/EarthEngine_Jeremy-privatekey.p12'
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ee.Initialize(ee.ServiceAccountCredentials(MY_SERVICE_ACCOUNT, MY_PRIVATE_KEY_FILE))
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## set map center to speed up viewing
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ee.mapclient.centerMap(-121.767, 46.852, 11)
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#///////////////////////////////////
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#// Function to extract cloud flags
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def getmod09(img): return(img.select(['state_1km']).expression("((b(0)/1024)%2)"));
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#// Date ranges
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yearstart=2000
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yearstop=2010
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monthstart=1
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monthstop=12
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#////////////////////////////////////////////////////
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# Loop through months and get monthly % missing data
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## set a year-month if you don't want to run the loop (for testing)
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year=2001
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month=1
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for year in range(yearstart,yearstop+1): {
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for month in range(monthstart,monthstop); {
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print('Processing '+str(year)+'_'+str(month))
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## MOD09 internal cloud flag for this year-month
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## to filter by a date range: filterDate(datetime.datetime(yearstart,monthstart,1),datetime.datetime(yearstop,monthstop,31))
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mod09 = ee.ImageCollection("MOD09GA").filter(ee.Filter.calendarRange(year,year,"year")).filter(ee.Filter.calendarRange(month,month,"month")).map(getmod09);
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## calculate mean cloudiness (%), rename band, multiply by 100, and convert to integer
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mod09a=mod09.mean().select([0], ['MOD09_'+str(year)+'_'+str(month)]).multiply(ee.Image(100)).byte();
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## print info to confirm there is data
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#mod09a.getInfo()
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## add to plot to confirm it's working
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#ee.mapclient.addToMap(mod09a, {'range': '0,100'}, 'MOD09')
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## define region for download
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region='[[-72, -1], [-72, 11], [-59, 11], [-59, -1]]' #h11v08
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# '[[-90, -1], [-90, 20], [-49, 20], [-49, -1]]' // Northern S. America
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# '[[-180, -90], [-180, 90], [180, 90], [180, -90]]' //global
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# '[[-180, -60], [-180, 90], [180, 90], [180, -60]]' // Western Hemisphere
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## build the URL and name the object (so that when it's unzipped we know what it is!)
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path =mod09a.getDownloadUrl({
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'name': 'mod09_'+str(year)+"_"+str(month), # name the file (otherwise it will be a uninterpretable hash)
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'scale': 926, # resolution in meters
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'crs': 'EPSG:4326', # MODIS sinusoidal
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'region': region
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});
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## download with wget
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wget.download(path)
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}}
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