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Below are my responses to your questions: 1) MERRA-2 does not provide your requested parameters at the vertical levels of interest. The variables you listed are vertically integrated quantities (i.e., column values). 2) Please refer to the tutorial I shared in my previous message. Please refer to mo...

Dear user, Thank you for sharing your download script. Based on our review, it appears you are using our on-premises OPeNDAP service to download the 2D MERRA-2 collection. To better assist you, could you please let us know which specific files you encountered issues with, along with examples of file...

Dear User, Please share examples of the URLs that are returning error files, along with URLs that successfully return valid files, and the exact command you used to download the data (e.g., wget or curl). We’d also like to check whether this issue may be related to reprocessed granules that use a sl...

If you study the long-term change of aerosols, you may want to consider the monthly aerosol collection tavgM_2d_aer_Nx (M2TMNXAER). Adding to Allie's reply, which is good, the MERRA-2 FAQ may provide you additional information (https://gmao.gsfc.nasa.gov/gmao-products/merra-2/faq_merra-2/). You can ...

naluru wrote: ↑Fri Nov 14, 2025 3:39 pm America/New_York POWER does not apply a transformation to the parameter, and this is indeed a mistake in the metadata. Thank you for bringing our attention to this detail. The updated definition should be reflected shortly.

Please let us updated once this definition is corrected in your website. Thanks.

The 3D collection M2I3NVAER (https://disc.gsfc.nasa.gov/datasets/M2I3NVAER_5.12.4/summary?keywords=M2I3NVAER_5.12.4) includes the mixing ratio for all five aerosol species, OC, BC, sulfate, dust, and sea salt. Below is a list of variables in this collection: air_density Hydrophilic Black Carbon Hydr...

Dear user, Thank you for your interest in MERRA-2 data! There are no differences in how the various MERRA-2 collections are accessed. We tested downloading the file MERRA2_400.tavgM_3d_tdt_Np.201906.nc4 and did not encounter any issues. Could you please try again? If the problem persists, we would a...

After reviewing your URL, it seems the issue may be related to the value you entered for "Horizontal Stride." This parameter controls the interval at which latitude and longitude points are sampled—essentially acting like the increment in a loop. For example, a stride of 1 means every grid...

Before retrying, make sure to clear your browser cache or try using a different web browser. To assist you more effectively, please provide the exact error message you received, along with the "NCSS Request URL" that triggered the issue. This URL is displayed just above the "Submit&qu...

Dear user, Please try again by narrowing the time range for each attempt — for example, subset one month per attempt. A large volume of data request may result in the error of "Internal Service Error". https://goldsmr4.gesdisc.eosdis.nasa.gov/thredds/ncss/grid/MERRA2_aggregation/M2T1NXAER....