ERDDAP has an email/URL subscription system so that you can be notified immediately whenever
a dataset changes (for example, whenever new data is added to a near-real-time dataset).
The system can send you an email or contact a URL that you specify.
See also this comparison
with ERDDAP's RSS subscription service.
Or, you can request an email with a
list of your valid and pending subscriptions.
It includes URLs to remove each of your subscriptions.
ERDDAP, Version 1.74