Subject: stream flow result Posted: 1/5/2016 Viewed: 16633 times
I have given input of stream flow a constant value for the whole year and while i extracted result for stream flow for the same node, it shows different values for each months (annual total value is same). Can anyone help me to find out the reason?
Thanks
Ms. Stephanie Galaitsi
Subject: Re: stream flow result Posted: 1/5/2016 Viewed: 16618 times
Dear Harshana,
This is a great example of how units are important. The data you entered for river streamflow is in cubic meters per second (CMS), which is a flow rate. If you are looking at the results under Supply and Resources/River/Streamflow, those results are in cubic meters (volume).
This would not matter if all the time steps were equal lengths, but they're not - February is much shorter, and the other months change between 30 and 31 days. So while the flow rate stays the same, the total monthly volume of flow will differ.
As a general rule, if you ever see weird results for February repeating themselves each year, take a moment to think about the units because it often has something to do with February being a short month.
Ms. Harshana Shrestha
Subject: Re: stream flow result Posted: 1/5/2016 Viewed: 16610 times
Thank you very much, yes there is great fall in the value of February than in other months. I was not able to analyse in this way.
Thanks.
