Changes between Version 2 and Version 3 of Branches/Driver_Improvements

Timestamp:

2012-09-13T10:31:57+02:00 (12 years ago)

Author:

nvuilsce

Comment:

--

Branches/Driver_Improvements

@@ -19 +19 @@
 == Add an explicit time information within the forcing files ==
 As described above, the driver of ORCHIDEE is relatively rigid because it only assumes one temporal specification for the forcing files. At first, we do not expect to develop a more flexible driver but we would like to add explicit time information in the driver in order to avoid misuse.
-We suggest to add time_bounds attributes to the variables stored in the NetCdf forcing files.
+We suggest to add a time_bounds attribute to the time variable stored in the NetCdf forcing files. See here for instance for a possible use: http://www.cgd.ucar.edu/cms/eaton/netcdf/NCAR-CSM.html
+It is not clear how to use the time_bounds attribute within a multi-variables file, in which the variables have different time specifications (instantaneous vs cumulative variables). The use of a time_op attribute (average, point) for each variable could be a solution. The time specification of a forcing file (based on time_bounds and time_op attributes) should be read by the driver, in order to check for consistency. 
+Questions that remain:
+ * How to implement in detail such a solution
+ * Is it an optional feature or do we request these specifications for any forcing file. 
 
+== Restart the last forcing time step read ==
+As the driver is built now, the first time step read (for the Temperature for instance) is valid for t+1. This means that for a yearly file at a 6-hourly time resolution, the first temperature read is for "1-JAN 06:00". For a simulation starting from scratch (no restart), the driver uses the first value for the second day ("2-JAN 00:00") in order to interpolate with the first one readed (and to calculate half-hourly values between "1-JAN 00:00" and "1-JAN 06:00". At the end of a simulation, the last forcing file read is not written in the restart file of the driver. When we perform monthly runs using a yearly forcing file, it is managed within the driver to use the appropriate time step in the forcing file but when we perform yearly runs using a yearly file, we process as for a run starting from scratch (while we could use the last values read during the last run). We suggest to restart the last time step read of the meteorological variables in order to be make possible this.
 
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+