swe.pi16 {nixmass}

Statistical SWE modeling depending on the day-of-year

Description

This model parameterizes bulk snow density with day-of-the-year as the only input. It was calibrated for the region of South Tyrol, Italy, and is therefore called ST model in the original reference.

Usage

swe.pi16(data, rho_0=200, K=1)

Arguments

data

A data.frame of daily observations with two columns named date and hs referring to day and snow depth at that day. The date column must be a character string with the format YYYY-MM-DD. The hs column must be snow depth values \ge 0 in m.

rho_0

Intercept of the linear regression between observed snow depths and SWE values. rho_0 is set to 200 as default, which is the value from the original reference. It can however be set to any value according to regression modeling with other datasets.

K

Slope of the linear regression between observed densities and the day-of-year as defined in the original reference. K is set to 1 as default, which is the value from the original reference. It can however be set to any value according to regression modeling with other datasets.

Details

swe.pi16 This function uses only the day-of-year (DOY) as parameterization for bulk snow density and hence SWE. Here, the datums in the input data.frame are converted to DOY as defined in the original reference: negative values between 1.10. and 31.12. DOY=-92 at 1.10. In leap years 31.12. has DOY = 0, in non-leap years 31.12. has DOY = -1 with no day being 0. Non computable values are returned as NA.

Value

A vector with daily SWE values in mm.

References

Pistocchi, A. (2016) 'Simple estimation of snow density in an Alpine region', Journal of Hydrology: Regional Studies. Elsevier B.V., 6(Supplement C), pp. 82 - 89. doi: 10.1016/j.ejrh.2016.03.004.