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GEE-MODIS影像MODIS/006/MOD09GQ数据暂时有问题

此星光明发表于 2022/12/05 11:07:15 2022/12/05

【摘要】问题：我注意到每日 MODIS 版本 061 （MODIS/061/MOD09GQ）存在已弃用的数据集没有的问题（MODIS/061/MOD09GQ）。在这里，您可以看到两个数据集中可用的第一张图像的日期相同，但是，当尝试加载两个图像时，061 版本找不到波段：I've noticed that version 061 of daily MODIS (MODIS/061/MOD09G...

问题：

我注意到每日 MODIS 版本 061 （MODIS/061/MOD09GQ）存在已弃用的数据集没有的问题（MODIS/061/MOD09GQ）。

在这里，您可以看到两个数据集中可用的第一张图像的日期相同，但是，当尝试加载两个图像时，061 版本找不到波段：

I've noticed that version 061 of daily MODIS (MODIS/061/MOD09GQ) is having problems where the deprecated dataset don't (MODIS/061/MOD09GQ).

Here you can see how the first image available in both datasets is of the same date, but however, when trying to load both images, the 061 version doesn't find bands:

Link: https://code.earthengine.google.com/dd44f9725cad62a3e4173adb10e48e22

Is there any problem with this new version 061?

官方回复

A few recent mosaics are timing out on ingestion. Trying to tune this.

最近的一些马赛克在引入时超时。试图调整这个。

代码：

 var table = ee.Geometry.Polygon([[-123.33565602090923, 36.191180192685735],
  [-118.35884938028423,36.191180192685735],
  [-118.35884938028423,38.52246956396676],
  [-123.33565602090923,38.52246956396676],
  [-123.33565602090923,36.191180192685735]]);
  
var dataset006 = ee.ImageCollection('MODIS/006/MOD09GQ')
    .filterBounds(table); 
var historical006 = dataset006.limit(1, 'system:time_start', false)
var firstImage006 = historical006.first();
print(firstImage006, 'firstImage006');
var doi006 = firstImage006.get('system:time_start');
var dateFirst006 = ee.Date(doi006)
print(dateFirst006)

var dataset061 = ee.ImageCollection('MODIS/061/MOD09GQ')
    .filterBounds(table); 
var historical061 = dataset061.limit(1, 'system:time_start', false)
var firstImage061 = historical061.first();
print(firstImage061, 'firstImage061');
var doi061 = firstImage061.get('system:time_start');
var dateFirst061 = ee.Date(doi061)
print(dateFirst061)


var day1 = dateFirst061 
var day2 = dateFirst061.advance(-1, 'day')


var collection1 = ee.ImageCollection('MODIS/006/MOD09GQ')
                  .filter(ee.Filter.date(day2, day1))
                  .filterBounds(table);

var collection_med1 = collection1.median();
var image1 = collection_med1.clip(table);
var ndvi1 = image1.expression(
    '((NIR - RED) / (NIR + RED))', {
      'NIR': image1.select('sur_refl_b02'),
      'RED': image1.select('sur_refl_b01'),});
Map.addLayer(ndvi1, {min:-0.2, max:1}, 'ndvimask1');

var collection61 = ee.ImageCollection('MODIS/061/MOD09GQ')
                  .filter(ee.Filter.date(day2, day1))
                  .filterBounds(table);

var collection_med61 = collection61.median();
var image61 = collection_med61.clip(table);
var ndvi61 = image61.expression(
    '((NIR - RED) / (NIR + RED))', {
      'NIR': image61.select('sur_refl_b02'),
      'RED': image61.select('sur_refl_b01'),});
Map.addLayer(ndvi61, {min:-0.2, max:1}, 'ndvimask61');