Irminger Glider 538 data access

HelpDesk
1

Hi OOI team,

I’m new to glider data so apologies if this information is on your website and I just haven’t been able to track it down. I’m interested in using the chlorophyll, temperature, and salinity data from glider 538 and initially downloaded it from the Data explorer, both the raw.nc and processed.nc files found in the top right corner under “Downloads”. The data appear to have good temporal and depth coverage, however the times aren’t in chronological order and the time midpoints don’t seem to actually correspond to the midpoint of individual profiles.

I then downloaded what I thought was the same data from both the IOOS Glider DAC and ERDDAP, however the temporal resolution of the chlorophyll data is much more sparse and cuts in and out during individual profiles, but this is not the case for temperature.

Any insights or advisement as to which files are recommended for use, and if there’s any published information on how the data explorer files are processed, would be much appreciated!

Thanks,

Meg

Screenshot 2025-12-08 at 9.53.04 AM
Screenshot 2025-12-08 at 9.53.04 AM1556×1050 222 KB

2

Hi Meg,

Thank you for reaching out with this question about glider data. Our glider team is looking into it and will follow up with a response as soon as possible.

Thank you,

Collin

3

Hi Meg,
This might be a good question for Stace: sbeaulieu@whoi.edu
Mike

4

Might be good to bring @jglatstein into the conversation…

5

Hi Meg, after some quick plotting on the Glider DAC ERDDAP, I think the “delayed mode” dataset will give you finer resolution like the Data Explorer product. You can see the difference in these two plots from Glider DAC data:

Glider 538 2024-06-12 (telemetered):

gi_538-202406_202410-telemetered_chl
gi_538-202406_202410-telemetered_chl360×440 12.5 KB

Glider 538 2024-06-12 delayed (recovered):

gi_538-202406_202410-recovered_chl
gi_538-202406_202410-recovered_chl360×440 24.4 KB

Personally, I would use data from the Glider DAC, since I’m not sure if there is some binning and aggregating of data when the Data Explorer product is created.

Cheers, Kylene

6

Thanks @kcooley ! I think I was unknowingly using the telemetered from the ERDDAP. Good to know the data explorer likely has some sort of binning going on.