MARS

Specifies the time difference in hours between an analysis time and the end of the assimilation window used to produce that analysis.

anoffset=<value>

This keyword has been introduced in preparation for overlapping 4DVAR windows and is used in the long-window systems, e.g.
Ensemble Data Assimilation [EDA], stream=elda and Deterministic High Resolution [HRES], stream=lwda

Valid values:

Example: Long window data assimilation analysis valid at 0 UTC, with an assimilation window closing at 9 UTC

...
anoffset=9,
class=od,
date=2018-11-01,
stream=lwda,
time=00:00:00,
type=an,
...

Dissemination

Not supported.