The sequence simulation can be used when you have several meteorological forecasts that you would like to use to simulate hydrological forecasts for on the same HYPE model.

When invoked from the command line, HYPE takes up to three command line arguments (How to run HYPE). The most common one is the path to the info.txt file. Here we will describe the use of the optional argument for sequence number. The sequence number is used to specify the forcing data to be used for a simulation among other forcing data, each forcing data set unique by their sequence number.

A simulation for sequence seqnr (where seqnr could by any integer between 0 and 999) is started by the command

$ ./hype ./path/to/info/ -s <seqnr>

The sequence number determines which forcing files to use. seqnr 0 uses forcing files without sequence number. If not using the command line, the sequence number can be specified similarily in the filedir.txt.

The forcing files are meterological forcing data (see Table here link Observation data files under info.txt), and can be either as text files or netcdf files. The forcing files are found in the forcingdir specified in info.txt. The correct files are found by looking for the file with the sequence number in the file name. The sequence number is given as a 3 digit integer after and underscore. E.g. Pobs_nnn.txt holds precipitation forcing data for sequence with seqnr nnn. For seqnr 0 Pobs.txt etc. is used. The ForcKey.txt file, if used, follows the forcing data and has the same sequence number.

The hyss.log file will always have a sequence number in its file name. Most result files get the sequence number in the file name for a sequence simulation. It is possible to write results without the sequence number in the filename. This is set by the resseqnr flag in info.txt (Yes or No, Yes is default). Some result files are not writing the sequence in their name. This is the case for the nutrient transport files (yyyy_ss.txt) and the water balance files (Wbf_xxx.txt, Wbff_xxx.tx, Wbfs_xxx.txt and Wbs_xxx.txt länkar).

State files do not use sequence numbers, neither for reading the initial state or for writing and output state. Thus the same statefile found in forcingdir will be used for all sequence simulations with a collection of forcing data sequence files in that folder.