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Adding new transformation and warm state

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Trevor Lumsden, modified 1 Year ago.

Adding new transformation and warm state

Youngling Posts: 10 Join Date: 2/14/17 Recent Posts
Good Day

I would like to know if it is possible for a user to develop and add a new transformation that is not available in the existing set. Would this require access to the Delft-FEWS source code, and therefore only be possible for Deltares to do themselves? Could a new transformation be treated a bit like an external module where the user just writes an adapter?

I would also like to know if a warm state (for initializing the hydrological/hydraulic model) can optionally include some observations (if these are available), or whether the state is purely based on the previous model simulation.

As background to my questions, I am currently evaluating whether Delft-FEWS could assist me in research related to seasonal hydrological forecasting. At this timescale it is often necessary to downscale climate forecasts to a suitable temporal and spatial scale. There are some techniques that I have in mind to do this, however, these are not available in the existing set of transformations as the latter are more geared towards short term flood forecasting (in keeping with the original purpose of FEWS).

Thanks

Trevor
transformation
Arnejan van Loenen, modified 1 Year ago.

RE: Adding new transformation and warm state

Padawan Posts: 70 Join Date: 5/29/12 Recent Posts
Hi Trevor,

I hope this reply is still useful!

1) Custom transformations: yes this is possible. Please have a look at this page on our WIKI:
https://publicwiki.deltares.nl/display/FEWSDOC/Custom+Transformations
Developing your own java code would provide the best performance. But, it is also possible to write a transformation in a different language and connect it via the General Adapter. We do this quite often with scripts written in Python

2) Include observations in warm state: this is actually a form of data assimilation. We have not integrated this functionality in Delft-FEWS, but are involved in the open-source DA toolkit Openda: http://openda.org/. This toolkit connects seamless to Delft-FEWS, although use and configuration requires knowledge on the subject.

3) use of Delft-FEWS for seasonal hydrological forecasting: actually Delft-FEWS is being used a lot for this kind of purposes. Therefore I'm interested in the types of transformations that you think are not possible. Maybe the papers on the portal give an idea about the possibilities: http://oss.deltares.nl/web/delft-fews/papers

best regards,
Arnejan
TL
Trevor Lumsden, modified 1 Year ago.

RE: Adding new transformation and warm state

Youngling Posts: 10 Join Date: 2/14/17 Recent Posts
Hi Arnejan

Thanks for answering my questions - the information is still useful to know.

Since writing the post I was fortunate to meet someone from Deltares who shared some info on seasonal applications of FEWS. This revealed that there are many analyses that are possible at seasonal timescales that I was not aware of.

Best regards
Trevor
Arnejan van Loenen, modified 1 Year ago.

RE: Adding new transformation and warm state

Padawan Posts: 70 Join Date: 5/29/12 Recent Posts
Hi Trevor,

I'm happy to hear you got to learn about the seasonal applications of Delft-FEWS. There are so many types of applications that Delft-FEWS can be used for emoticon

regards,
Arnejan