前言:主要介绍利用GEE获取Modis下的GPP数据。
var geometry = ee.FeatureCollection('users/www1573979951/luyixian');
Map.centerObject(geometry,6);
var dataset = ee.ImageCollection('MODIS/006/MOD17A2H').filter(ee.Filter.date('2014-01-01', '2014-12-31'));
print(dataset)
var npp = dataset.select('Gpp');
var nppVis = {
min: 0.0,
max: 19000.0,
palette: ['bbe029', '0a9501', '074b03'],
};
Map.addLayer(npp.mean().clip(geometry), nppVis, 'NPP');
主要有Gpp、PsnNet、Psn_QC指数
var geometry = ee.FeatureCollection('users/www1573979951/luyixian');
Map.centerObject(geometry,6);
var dataset = ee.ImageCollection("MODIS/006/MYD17A2H")
.filter(ee.Filter.date('2010-01-01', '2010-12-31'))
.filterBounds(geometry);
print(dataset);
var geometry = ee.FeatureCollection('users/www1573979951/luyixian');
Map.centerObject(geometry,6);
var dataset = ee.ImageCollection("MODIS/006/MYD17A2H")
.filter(ee.Filter.date('2010-01-01', '2010-12-31'))
.filterBounds(geometry).select('Gpp');
print(dataset);
var gppVis = {min: 0.0, max: 600.0, palette: ['bbe029', '0a9501', '074b03']};
Map.addLayer(dataset.mean().clip(geometry), gppVis, 'Gpp');//2010年的均值
var geometry = ee.FeatureCollection('users/www1573979951/luyixian');
Map.centerObject(geometry,6);
var dataset = ee.ImageCollection("MODIS/006/MYD17A2H")
.filter(ee.Filter.date('2010-01-01', '2010-12-31'))
.filterBounds(geometry).select('Gpp');
print(dataset);
function exportImageCollection(imgCol) {
var indexList = imgCol.reduceColumns(ee.Reducer.toList(), ["system:index"]).get("list");
indexList.evaluate(function(indexs) {
for (var i=0; i<indexs.length; i++) {
var image = imgCol.filter(ee.Filter.eq("system:index", indexs[i])).first();
image = image.clip(geometry);
//tif数据下载
Export.image.toDrive({
image: image,
description: 'modis_gpp_'+indexs[i],
fileNamePrefix: 'modis_gpp_'+indexs[i],
folder: 'Modis',
region: geometry,
scale: 500,
crs: "EPSG:4326",
maxPixels: 1e13
});
}
});
}
exportImageCollection(dataset);
var geometry = ee.FeatureCollection('users/www1573979951/luyixian');
var dataset = ee.ImageCollection("MODIS/006/MYD17A2H");
for(var i=2018;i<=2020;i++){
for(var j=1;j<=12;j++){
var data_collection = null;
switch(j){
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:
data_collection = dataset.filterDate(i+'-'+j+'-01',i+'-'+j+'-31').select('Gpp');
break;
case 4:
case 6:
case 9:
case 11:
data_collection = dataset.filterDate(i+'-'+j+'-01',i+'-'+j+'-30').select('Gpp');
break;
case 2:
data_collection = dataset.filterDate(i+'-'+j+'-01',i+'-'+j+'-28').select('Gpp');
break;
}
var YR_collection = data_collection.sum().clip(geometry);//如果报错的话加在sum后面加上.toDouble()
Export.image.toDrive({
image: YR_collection,
description: i+'-'+j,
fileNamePrefix: i+'-'+j,
scale: 500,
region: geometry,
crs: "EPSG:4326",//投影方式
maxPixels: 1e13,
folder: 'Modis'
})
}
}
var geometry = ee.FeatureCollection('users/www1573979951/luyixian');
var dataset = ee.ImageCollection("MODIS/006/MYD17A2H");
for(var i=2018;i<=2020;i++){
var data_collection = dataset.filterDate(i+'-01-01',i+'-12-31').select('Gpp');
// print(data_collection)
var YR_collection = data_collection.sum().clip(geometry);//如果报错的话加上在sum后面加上.toDouble()
Export.image.toDrive({
image: YR_collection,
description: i,
fileNamePrefix: i,
scale: 500,
region: geometry,
maxPixels: 1e13,
crs: "EPSG:4326",//投影方式
folder: 'Modis'
});
}