datetime	date yyyy-mm-dd hh:mm:ss [UTC]
at	Air temperature is the bulk temperature of the air at 2m [°C]
relh	Relative humidity at 2m [%]
apress	Atmospheric pressure [hPa]
ir	longwave radiation total [W/m2]
uva	Radiation UV-A total [W/m2]
iravg	longwave radiation mean [W/m2]
irmin	longwave radiation min [W/m2]
irmax	longwave radiation max [W/m2]
min_wind_speed	"	min wind speed [m/s]"
max_wind_speed	max wind speed [m/s]
wind_speed	"	mean wind speed [m/s]"
wind_dir	mean wind direction [°]