modules_annandale (07/19/10)

Annandale

Defined in ClassAnnandale. The purpose of this module is to estimate incoming short wave radiation from daily minimum and maximum temperatures when no other radiation observations are available. Annandale et al. (2001) developed a simple emipirical method for estimating transmittance from the daily range of air temperature.

Observations

• none

Variables

• TauA () -  transmittance calculated from the Annandale method.
• hru_SunAct (h) - calculated sunshine hours.

Parameters

• krs () - location index, interior = 0.16 and coastal = 0.19.
• hru_elev (m) - HRU elevation.

Variable Inputs

• hru_tmax (*) (°C) - daily maximum temperature.
• hru_tmin (*) (°C) - daily minimum temperature.
• QdroDext (*) (MJ/m^2*d) - daily ExtraTerrestrial direct.
• QdflatD (*) (MJ/m^2*d) - daily clear-sky Qdro (with diffuse) on horizontal surface.
• QdflatE (*) (W/m^2) - 'Qdro' on horizontal surface, no atmosheric attenuation.
• Qdro (*) (W/m^2) - clear-sky direct with GSL and ASL applied.
• Qdfo (*) (W/m^2) - clear-sky diffuse with GSL and ASL applied.
• QdfoD (*) (MJ/m^2*d) - daily average clear-sky diffuse.
• SunMax (*) (h) - maximum sunshine hours.

Observation Variables

• QsiA (W/m^2) - interval synthesized short-wave derived from Annandale method.
• QsiD (W/m^2) - daily synthesized short-wave derived from Annandale method.
• QsiS (W/m^2) - synthesized short-wave on slope derived from global Qdro and Qdfo, and the Annandale method.