Changes between Version 2 and Version 3 of U_next_observation

Timestamp:

Mar 30, 2023, 11:50:26 AM (2 years ago)

Author:

lnerger

Comment:

--

U_next_observation

@@ -12 +12 @@
  * `stepnow` : `integer, intent(in)`[[BR]] Number of the current time step
  * `nsteps` : `integer, intent(out)`[[BR]] Number of time steps until next observations are available
- * `doexit` : `integer, intent(out)`[[BR]] Whether to exit forecasting (1 for exit); only relevant for the 'flexible' implementation variant.
+ * `doexit` : `integer, intent(out)`[[BR]] Whether to exit forecasting (1 for exit); only relevant for the 'flexible' implementation variant; set =0 for 'fully parallel' variant.
  * `timenow` : `real, intent(out)`[[BR]] Current model (physical) time at the beginning of the current forecast phase; only relevant for the 'flexible' implementation variant.
 
@@ -22 +22 @@
  * If the time interval between successive observations is known, `nsteps` can be simply initialized by dividing the time interval by the size of the time step
  * At the first call to `U_next_observation` the variable `timenow` can be initialized with the current model time. At the next call a forecast phase has been completed. Thus, the new value of `timenow` follows from the time interval for the previous forecast phase.
+ * `doexit` is not relevant for the fully-parallel implementation. It is recommended to set `doexit=0`. In this case the data assimilation process will just end when the model integrations are completed.
+ * If `nsteps=0` or `doexit=1` is set, the ensemble state will not be distributed by PDAF (i.e. `distribute_state` is not called). If one intends to proceed with ensemble forecasting, one has to set nsteps to a value >0 and `doexit=0`. If nsteps is set to a value larger than the last time step of the model no further analysis step will be performed.