Earthdata Forum

Hello,

I’ve been having some difficulty with accessing the MERRA2_CNN_HAQAST_PM25 dataset. I first noticed the issue when using the EarthAccess package in Python. Here is an example:

# install & import the required packages:
!pip install --quiet earthaccess
import earthaccess

# Login:
earthaccess.login()

# Search:
earthaccess.search_data(
  short_name='MERRA2_CNN_HAQAST_PM25',
  bounding_box=(29,-2,32,1),
  temporal=('2024-10-01 00:00:00','2024-10-31 23:59:59')
)

The result is an empty list, indicating no data meet the search query.

I tried reproducing the search from the EarthData search website:
https://search.earthdata.nasa.gov/search?p=!C3094710982-GES_DISC&q=MERRA-2%20CNN%20PM2.5&sb[0]=29%2C-2%2C31%2C1&qt=2024-10-01T00%3A00%3A00.000Z%2C2024-10-31T23%3A59%3A59.999Z&lat=-0.5&long=30.077479338842974&zoom=7.825753832883113

Again, the result is 0 granules found.

However, when I try to access the data via the dataset landing page (https://disc.gsfc.nasa.gov/datasets/MERRA2_CNN_HAQAST_PM25_1/summary) using the "Get Data" button, I get a valid list of files, for example:

https://data.gesdisc.earthdata.nasa.gov/data/HAQAST/MERRA2_CNN_HAQAST_PM25.1/2024/MERRA2_HAQAST_CNN_L4_V1.20241001.nc4
...
https://data.gesdisc.earthdata.nasa.gov/data/HAQAST/MERRA2_CNN_HAQAST_PM25.1/2024/MERRA2_HAQAST_CNN_L4_V1.20241031.nc4

I notice the last date of available data in Earthdata Search and Earthaccess seems to be June 1, 2024 for the dataset.

I’m wondering if there is an issue with how these data are being indexed to the Common Metadata Repository  which is preventing them from showing up in some search functionalities.

Thanks,

- Carl

Hello Carl,

Thank you for reporting this. We were able to verify that the granules do exist, but for some reason, certain granules have a sub-global bounding box limit in their CMR records. In October 2024, they have a bounding box limit over North America ([21.1546, -131.6533, 53.03837, -58.79196]), which could be a metadata ingest error, or something not documented elsewhere.

We will continue to investigate and respond when we have more information.

Regards,
GES DISC User Services