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All Topics | Topic "Scenario Analysis"
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Author Message
Mitika Farkya

Subject: Scenario Analysis   
Posted: 5/30/2015 Viewed: 7796 times
Hello Sir/Ma'am,
I am working on Interbasin water transfer using WEAP.
If I have inflow data from 1976 to 2013, then what should be my current account year.
Also I am introducing the point for comparision like;
* What if Diversion link is included in the system of rivers?
* What if Reservoir is constructed along the rivers?
and so on...are the points correct for analysis?
And If I want to include the cropping pattern for scenario analysis, how could I do that?
Your suggestion would be very helpful for me.

Stephanie Galaitsi

Subject: Re: Scenario Analysis   
Posted: 6/1/2015 Viewed: 7765 times
Dear Mitika,

Good questions. I'll answer them in order.

1) Your Current Accounts year should be a year that you have data for. This will serve to characterize the whole system. I would recommend have it be fairly far in the past - that will give you the opportunity to compare the inflow data you have with the inflow data that your model will generate. You will want them to be as close as possible, and the more years you have to compare, the better you'll be able to judge. You could start all th way back in '76, or more recently, like 2003, so you have a ten year calibration period.

2) Your points for comparison sound great. I suggest uses the Scenarios analysis feature in WEAP to develop these, and then you will be able to compare them to the baseline ("reference") scenario.

3) To study cropping area, I would suggest using catchments and subdividing which crops you have, and their hectares, and comparing them to potential future land use for the same crops. The Catchments module in the tutorial (www.weap21.org/tutorial) will teach you how to subdivide catchments by land use, and then you can build a scenario in which those subdivisions change.

Good luck!
Mitika Farkya

Subject: Re: Scenario Analysis   
Posted: 6/3/2015 Viewed: 7754 times
Dear Ma'am
Thank you so much for the detailed answers.
now I am taking current accounts as 2003, but if I need to develop the scenario for future like upto 2030 or 2050, then what should be my last year, since the data available is from 2003 to 2013.
and Is there any option to compare the inflow generated by WEAP and the data I have?

Stephanie Galaitsi

Subject: Re: Scenario Analysis   
Posted: 6/10/2015 Viewed: 7726 times
Dear Matika,

Your scenario years will start the year after the Current Accounts year and go until the end of your model (the same as the Reference Scenario that you see in your results). You have two choices for how to manage your model. For both, start with the ten year calibration period to make sure that all the data inputs are able to match the data outputs you already have. Then you can:

1) Change the years that your model covers in the General menu/Years and Timesteps. If you do this, make sure that any "growth" (for example, population) equations are starting from the correct time that you want to start your model from. You can also save your calibrated time period as a model version (just keep in mind that if you edit it for any reason, you'll have to save a new version).

2) Use your same model and keep the calibration period, but extend your model out in the General menu/Years and Time steps, and then for any scenario, be mindful of when you specify the implementation of the change you're examining. For example, a wastewater treatment plant can be built on the schematic but not active in Current Accounts, and then you specify the start year of operation (you also must build the transmission links and return flow accordingly - see the Water Quality module in the WEAP Tutorial). That way you can more tightly control the deviation of the scenarios from the Reference Scenario. You can also use this same technique with the first option as well.

Of this two options, we tend to use the first one, but you can do whichever suits you better.
Mitika Farkya

Subject: Re: Scenario Analysis   
Posted: 6/24/2015 Viewed: 7594 times
Hello Mam,
If I have Montly inflow series from 1990 to 2012 in unit MCM (Million Cubic Meter) and in software the unit is CMS (Cubic Meter per Second), So how to convert the data in MCM to CMS
Kindly suggest any conversion factor

Thank You
With Best Regards
Robert Ojwang

Subject: Re: Scenario Analysis   
Posted: 6/24/2015 Viewed: 7590 times
Hi Mitika,
Am also new to WEAP like you but I think you can divide your monthly flows by (days of the month*24*3600) e.g. for January you divide by 31*24*3600.
I hope this helps.
Jack Sieber

Subject: Re: Scenario Analysis   
Posted: 6/25/2015 Viewed: 7584 times
In General, Years and Timesteps, you can choose if all timesteps have the same number of days, or are based on the calendar. In WEAP expressions, you can use the built-in variable DAYS to refer to the number of days in each timestep, which is useful if the number of days varies by month.

Therefore, to convert from MCM to CMS, you would multiply by:

1000000 / (Days * 24 * 3600)
Mitika Farkya

Subject: Re: Scenario Analysis   
Posted: 7/1/2015 Viewed: 7562 times
Dear Sir,
Thank you very much for valuable solution.
There are some more question, please support for better results.
1. In data view, under the heading hydrology, we have to input any data (Water year method/ASCII file) or If I have imported data for individual river is Okay?
2. If I have inflow data from 1990 to 2008 and I have to simulate the model upto 2015, The inflow data should be extended upto 2015 or not?
3. And If I have to run the model simulation upto 2050 what should be done?

Thank you
With Regards

Stephanie Galaitsi

Subject: Re: Scenario Analysis   
Posted: 7/5/2015 Viewed: 7549 times
Hi Mitika,

1) The Water Year Method is to extend whatever river hydrology you have plugged into the Current Accounts year forward into the future of your model. I would recommend doing the Water Year Method activity in the tutorial to understand how this works.

2)You will have to decide how to simulate your data from 2008 - 2015. There are many different methods. The Water Year method is one.

3) You will have to make the same choice for simulation to 2050. Modellers don't know the future, but we can ask questions that show what it might look like. You know your watershed best - what kind of questions are being asked there?
Topic "Scenario Analysis"