module_slope_Qsi (04/08/08)

CRHM Borland

Slope_Qsi.

This module estimates Qsi for a slope from the measured incoming short-wave Qsi on the level.  The ratio of measured Qsi and the calculated clear sky direct and diffuse on a horizontal plane is used to adjust the calculated clear sky value on the slope.

Observations

  • Qsi (W/m^2) - incident short-wave measured on a level plane.

Variables

  • Short (W/m^2) - Calculated Qsi for the slope equal to Qdro + Qdfo.
  • ShortC (W/m^2) - Qsi corrected for slope from the ratio of (measured Qsi)/Qdflat.

Parameters

  • none.

Variable Inputs

  • Qdro (global) (W/m^2).
  • Qdfo (global) (W/m^2).
  • Qdflat  (global)(W/m^2).

Observation Variables

  • Qsi# (W/m^2) - Qsi corrected for slope.

Truncation note.

    In this implementation there is truncation at either sunrise or sunset since the alogorithm is only active when the incoming net short wave radiation on the level is positive. This means that any incoming radiation due to the slope at before dawn and after dusk is ignored unless the incoming is positive on the level.