Tool Growing Degree Days
This tool calculates growing degree days from daily or from spline interpolated monthly observations for a given threshold. It also calculates the julian day at which a specific target temperature sum is reached. 
- Author: D.N. Karger (c) 2017
 
- Menu: Climate and Weather|Bioclimatology
 
Parameters
|   | Name | Type | Identifier | Description | Constraints | 
| Input | Mean Monthly Temperatures | grid list, input | TMEAN | Monthly (12) temperature observations. | - | 
| Output | Number of Days above Base Temperature | grid, output | NGDD | Number of days above base temperature. | - | 
 | Growing Degree Days | grid, output | TSUM | Integral of daily temperature above base temperature. | - | 
 | First Growing Degree Day (*) | grid, output, optional | FIRST | First growing degree day of the year (1-365). | - | 
 | Last Growing Degree Day (*) | grid, output, optional | LAST | Last growing degree day of the year (1-365). | - | 
 | Degree Sum Target Day (*) | grid, output, optional | TARGET | Day of the year at which temperature sum is reached (1-365). | - | 
| Options | Grid System | grid system | PARAMETERS_GRID_SYSTEM | - | - | 
 | Base Temperature | floating point number | TBASE | Base temperature in degree Celsius | Default: 10.000000 | 
 | Degree Sum | floating point number | TTARGET | Target temperature sum in degree Celsius. | Default: 100.000000 | 
| (*) optional | 
Command-line
Usage: saga_cmd climate_tools 18 [-TMEAN <str>] [-TBASE <double>] [-NGDD <str>] [-TSUM <str>] [-FIRST <str>] [-LAST <str>] [-TARGET <str>] [-TTARGET <double>]
  -TMEAN:<str>     	Mean Monthly Temperatures
	grid list, input
  -TBASE:<double>  	Base Temperature
	floating point number
	Default: 10.000000
  -NGDD:<str>      	Number of Days above Base Temperature
	grid, output
  -TSUM:<str>      	Growing Degree Days
	grid, output
  -FIRST:<str>     	First Growing Degree Day
	grid, output, optional
  -LAST:<str>      	Last Growing Degree Day
	grid, output, optional
  -TARGET:<str>    	Degree Sum Target Day
	grid, output, optional
  -TTARGET:<double>	Degree Sum
	floating point number
	Default: 100.000000