WATSON’s working group 3 has just finished a new R code called WITS dedicated to estimating transit time and storage in hydrological systems using isotopes.
The codes comes together with a whole series of accompanying reports. The code allows the user to choose a model from either the classical lumped parameter models or the storage selection functions, fit the model to a measured isotopic output, and then either iteratively improve the fit by adding elements to the basic model, or compare the performance of different models in reproducing observations.
The reports include (i) a complete modelling guide with WITS presenting the theory of input-output models, numerous examples and all the available modelling options, (ii) a short beginner’s manual guiding the new user through a simple example using WITS, (iii) a complete user manual detailing the structure of the R code behind WITS, (iv) a quick guide dedicated to sampling isotopes and (v) a short document on the effect of sampling frequency on the estimation of the young water fraction. WITS and all the documents can be found on the WATSON website and on Github.
