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.
Don't abuse this system by entering someone else's email address!
If you do, you may be blocked from using ERDDAP.