Welcome to WEAP's Website WEAP
WEAP is an initiative of the Stockholm Environment Institute.

About WEAP

What's New?
Sample Screens
History and Credits

Using WEAP
User Guide
Videos (YouTube)

User Forum
Members List
Edit Profile

Additional Support
University Courses

About Us
SEI-US Water Resources Program
Please Contact Us

Environmental News
Not acting like themselves: Antidepressants in environment alter crayf...
Expose crayfish to antidepressants, and they become more outgoing -- but that might not be such a positive thing for the...

Use of PFAS in cosmetics 'widespread,' new study finds
Many cosmetics sold in the United States and Canada likely contain high levels of per- and polyfluoroalkyl substances (P...

Baltic herring larvae appear earlier and grow faster due to climate ch...
Conditions during Baltic herring spawning may have cascading effects on the whole Baltic ecosystem.
Source: Science Daily
Interested in Energy?
Read about LEAP: SEI's software for energy planning.

Link WEAP and LEAP for combined Water-Energy planning.
Watch a video demo!

User Forum

All Topics | Topic "Weighted mean of high and low temperature: Soil Moisture Method"
Log in to post new messages or reply to existing messages.
Author Message
Mr. Mohammed Yassin

Subject: Weighted mean of high and low temperature: Soil Moisture Method   
Posted: 6/24/2016 Viewed: 7948 times
Hello WEAP community,
Under the rainfall-runoff (Soil Moisture Method) in WEAP, temperature is defined as the ‘Weighted mean of high and low temperature’? Could anyone please clarify what this means and how this value can be calculated?

For the case of my study area, temperature data are available in different forms and resolutions. Temperature is provided as on hourly basis, on daily basis as Maximum and Minimum values within each day, and on Monthly basis (i) Maximum and Minimum values for each month, and (ii) Mean Maximum and Mean Minimum Values for each month?
As I am intending to run the model using a monthly time step, and utilising the ReadFromFile wizard (i.e. time series for each catchment) how can I generate the appropriate temperature value to be used in rainfall runoff method to model my catchments?

Your answer is highly appreciated

Best Regards,
Mohammed Yassin

Ms. Stephanie Galaitsi

Subject: Re: Weighted mean of high and low temperature: Soil Moisture Method   
Posted: 6/26/2016 Viewed: 7905 times
Dear Mohammed,

The soil moisture method, when used monthly, needs temperature inputs for each month for each catchment. This has to be a single record of one temperature value/catchment/month. How you arrive at that number is up to you - you could use the average of maximum and minimum daily values, you could average the monthly maximum and minimum daily values, you can weight maximum values more than minimum, or vice versa. Average monthly temperature is common to use, but you could argue that your basin is different and use another representative temperature, it depends on your knowledge of your system. Modelers have to make a lot of judgment decisions, and you'll see the result of these decisions as you calibrate the model.

I would generate the time series within a Excel for CSV file, for simplicity's sake, and then use the ReadFromFile wizard.
Mr. Mohammed Yassin

Subject: Re: Weighted mean of high and low temperature: Soil Moisture Method   
Posted: 6/28/2016 Viewed: 7891 times
Dear Stephanie,

Thanks very mush for your answer and clarifications

Topic "Weighted mean of high and low temperature: Soil Moisture Method"