Easier access to CO-OPS data
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Reset the form to the default values.
Or, bypass this web page and do time conversions from within a computer program, script, or web page.
Notes about the Time Converter
The first word can be (upper or lower case):
ms, msec, msecs, millis, millisecond, milliseconds,
s, sec, secs, second, seconds,
m, min, mins, minute, minutes,
h, hr, hrs, hour, hours,
d, day, days,
mon, mons, month, months,
yr, yrs, year, or years.
"since" is required.
The time can be any time in the format yyyy-MM-ddTHH:mm:ss.SSSZ,
where Z is 'Z' or a ±hh or ±hh:mm offset from the Zulu/GMT time zone.
If you omit Z and the offset, the Zulu/GMT time zone is used.
Separately, if you omit .SSS, :ss.SSS, :mm:ss.SSS, or Thh:mm:ss.SSS, the
missing fields are assumed to be 0.
So another example is "hours since 0001-01-01".
Technically, ERDDAP does NOT follow the UDUNITS standard when converting "years since"
and "months since" time values to "seconds since". The UDUNITS standard defines a
year as a fixed, single value: 3.15569259747e7 seconds. And UDUNITS defines a month
as year/12. Unfortunately, most/all datasets that we have seen that use
"years since" or "months since" clearly intend the values to be calendar years
or calendar months. For example, "3 months since 1970-01-01" is usually intended
to mean 1970-04-01. So, ERDDAP interprets "years since" and "months since" as
calendar years and months, and does not strictly follow the UDUNITS standard.
How ERDDAP Deals with Time
Percent Encoding - The parameter values in the URL (the parts after '=' signs) must be properly
percent encoded: all characters other than A-Za-z0-9_-!.~'()* must be encoded as %HH,
where HH is the 2 digit hexadecimal value of the character, for example, a space becomes
%20. Characters above #127 must be converted to UTF-8 bytes, then each UTF-8 byte must
be percent encoded (ask a programmer for help). There are
web sites that percent encode and decode for you.