Th_int_series: Hourly interpolation of multiple daily temperature series
In Interpol.T: Hourly interpolation of multiple temperature daily series

Description Usage Arguments Value Note Author(s) References See Also Examples

The function creates sets of hourly temperature series, in a specified period, from minimum and maximum daily series. The calibration files, created by the functions par_calibration and shape_calibration, are loaded and passed to function Th_interp.

  Th_int_series(cal_times, TMIN, TMAX, start_year,
    end_year, cal_shape = NULL, active_IDs = NULL,
    min_mo.length = 21, full.24.hrs.span_min = TRUE,
    silent = FALSE)

`cal_times`	calibration table of "time" parameters for the specific series
`cal_shape`	calibration table for "shape" parameter for the specific series; default is `NULL`(don't use)
`TMIN`	minimum temperature daily table
`TMAX`	maximum temperature daily table
`start_year`	year of simulation start
`end_year`	year of simulation end
`active_IDs`	a set of series IDs to be interpolated. If `NULL` (default), all series are interpolated
`min_mo.length`	minimum number of days necessary to calculate monthly dtr values
`full.24.hrs.span_min`	logical, if set to `FALSE` does not allow to shift minimum time to the late hours of the day
`silent`	logical: if set to `TRUE` suppresses any warning issue

A list of interpolated hourly temperatures for the active_IDs series

TMIN and TMAX are data frames with the first three columns devoted to the date. The names of these columns must be "year", "month", and "day", irrespective of their order. Data series range from column 4 to the last.

If the series ID coincides with one with non-null results of the par_calibration function (enough data for calibration) its table is passed to the interpolation function, otherwise the average (cal_table) is used.

full.24.hrs.span_min is TRUE as default. If must be set to FALSE only if minimum values of the daily series have been calculated on a restricted time band, which is included in band_min (see function par_calibration). If this is the case, the minimum of the interpolated curve will always fall within band_min (early hours of the day). If this option is erroneously chosen, errors as large as 0.6 deg C can arise in the average of mean daily T.

Tmin of the day before the first is set = to Tmin of the first day and Tmin of the day after the last = Tmin of the last day.

Since the first value of T at sunset (of the day before) is NULL, the first hourly values produced till time_min are = Tmin.

Emanuele Eccel, Emanuele Cordano emanuele.eccel@iasma.it

Eccel, E., 2010: What we can ask to hourly temperature recording. Part II: hourly interpolation of temperatures for climatology and modelling. Italian Journal of Agrometeorology XV(2):45-50 http://www.agrometeorologia.it/documenti/Rivista2010_2/AIAM%202-2010_pag45.pdf

Original algorithm from: Cesaraccio, C., Spano, D., Duce, P., Snyder, R.L., 2001. An improved model for determining degree-day values from daily temperature data. Int. J. Biometeorol. 45: 161-169. http://www.springerlink.com/content/qwctkmlq3tebthek/

See also: Eccel, E., 2010: What we can ask to hourly temperature recording. Part I: statistical vs. meteorological meaning of minimum temperature. Italian Journal of Agrometeorology XV(2):41-43. http://www.agrometeorologia.it/documenti/Rivista2010_2/AIAM%202-2010_pag41.pdf

Th_interp, Mo.Th.Ra., date.time

library(Interpol.T)
data(Trentino_hourly_T)
stations <- c("T0001","T0010","T0129")
# interpolation of temperature for series T0001 and T0129, from 2004 to 2005
Th_int_list <- Th_int_series(cal_times = calibration_l,
						cal_shape = calibration_shape,
					    TMIN=Tn, TMAX=Tx,
                     start_year = 2004, end_year = 2005,
						active_IDs = stations)

Loading required package: date
Loading required package: chron
[1] Now processing series T0001
[1] Now processing series T0010
[1] Now processing series T0129