This function creates a new virtual sensor on locality within the myClim data object. Virtual sensor hosts values of snow cover presence/absence detected from temperature time-series.
mc_calc_snow(
data,
sensor,
output_sensor = "snow",
localities = NULL,
range = 1,
tmax = 1.25,
days = 3
)cleaned myClim object see myClim-package
name of temperature sensor used for snow estimation. (e.g. TMS_T2)
name of output snow sensor (default "snow")
list of locality_ids where snow will be calculated; if NULL then all (default NULL)
maximum temperature range threshold for snow-covered sensor (default 1°C)
maximum temperature threshold for snow-covered sensor (default 1.25°C)
number of days to be used for moving-window for snow detection algorithm (default 3 days)
myClim object with added virtual sensor 'snow' (logical) indicating snow presence/absence (TRUE/FALSE).
Function detects snow cover from temperature time-series. Temperature sensor is considered as covered by snow
when the maximal temperature in the preceding or subsequent time-window (specified by days param)
does not exceed specific tmax threshold value (default 1.25°C) and the temperature range remain below specified
range threshold (default 1°C). This function rely on insulating effect of a of snow layer,
significantly reducing diurnal temperature variation and restricting the maximal temperature near the ground
close to freezing point. Temperature sensor near the ground (TMS_T2) is default choice for snow-cover detection from Tomst TMS loggers.
Snow detection with default values accurately detects snow of depth > 15cm (unpublished data).
For detection of thin snow, range parameter should be set to 3-4 °C.
The function returns vector of snow cover (TRUE/FLASE) with same time-step as input data. To get number of days with snow cover
and more snow summary characteristics use mc_calc_snow_agg after snow detection.
data <- mc_calc_snow(mc_data_example_agg, "TMS_T2", output_sensor="TMS_T2_snow",
localities = c("A2E32", "A6W79"))