https://www.itc.nl/library/papers_2005/msc/ereg/harssema.pdf

http://hydrology.usu.edu/RRP/userdata/4/87/RainfallRunoffProcesses.pdf

You can try using Curve Number method to evaluate the response and to explore changes in runoff resulting specific input. This is a rough method as it involves many assumptions.

I recommend using simulation or multivariate methods:

Multivariate methods:  https://www.researchgate.net/publication/281809655_Effect_of_climate_and_land_cover_changes_on_watershed_runoff_A_multivariate_assessment_for_stormwater_management

Simulations: 

https://www.researchgate.net/publication/225525415_Effect_of_Climate_Change_on_Watershed_System_A_Regional_Analysis

Article Effect of climate and land cover changes on watershed runoff...

Article Effect of Climate Change on Watershed System: A Regional Analysis

Hi Priyank,

The runoff coefficient is the ratio of discharge (Q) and precipitation (P): Q/P. If you consider a long time period where the initial water storage is the same as the water storage (S) at the end of the period the water balance of a catchment is dS/dt = P-Q-ET where dS is the change in storage, t is time and ET is evapotranspiration. Since dS/dt = 0, Q = P-ET and the runoff coefficient becomes (P-ET)/P or 1 - ET/P showing directly the influence of ET on the runoff coefficient.

The effect of other climatological factors such as precipitation intensity, precipitation amount, dry spell length etc. can be investigated using a hydrological model which complexity will depend on data availability, aim of the modelling and spatial and temporal variability of relevant hydrological processes.

Regards,

Martijn

One way is to use a hydrologic model to compute runoff from rainfall - both for current and projected future conditions. From there, you can compute runoff coefficients and its change due to climate.

Dear Priyank, It is commonly assumed that the quantity (volume) of runoff is a proportion (percentage) of the rainfall depth. Runoff [mm] = C x Rainfall depth [mm]. In rural catchments where no or only small parts of the area are impervious, the coefficient C, which describes the percentage of runoff resulting from a rainstorm, is however not a constant factor. Instead its value is highly variable and depends on the above described catchment-specific factors and on the rainstorm characteristics. For example, in a specific catchment area with the same initial boundary condition (e.g. antecedent soil moisture), a rainstorm of 40 minutes duration with an average intensity of 30 mm/h would produce a smaller percentage of runoff than a rainstorm of only 20 minutes duration but with an average intensity of 60 mm/h although the total rainfall depth of both events were equal. Runoff coefficients for large watersheds should not be applied to small catchment areas. 

Hi

pay also attention to separate the different part of the time series that could be non stationnary. This can be done by applying some statistical methods like bayesian method. You can use the free khronostat software to do that.

http://www.hydrosciences.org/spip.php?article1000

click on "logiciel d'installation"

and then on "lisez moi"

Best

Gil

Article Analyse par les vecteurs régionaux de la variabilité spatio-...

Article Trends and Discontinuities in Regional Rainfall of West and ...