NicheMapR Microclimate Model

This new release includes a couple of corrections and some additional features.

One correction is to the soil moisture algorithm. The value in Campbell's program 11.1 for VP (saturation vapour density) is fixed at the value for 20 degrees C and this was copied into the microclimate model code. However, it should vary with temperature and this correction has now been made (using the WETAIR function internal to the microclimate model). It will affect near surface (<5 cm) soil moisture calculations in particular.

The other correction relates to the emissivity value for the substrate, SLE (soil long wave emissivity) which had been erroneously hardwired at a value of 0.9 in the Fortran code but was meant to be accessible to the user to change. This is now fixed (most substrates have an emissivity between 0.9 and 0.95).

The additional features are to make the following parameters from the soil moisture model available to the user to alter: root radius, resistance per unit length of root and leaf, critical leaf water potential for stomatal closure, stability parameter for stomatal closure equation, maximum allowable mass balance error for soil moisture, maximum iterations for mass balance of soil moisture.

Also, the wavelength-specific solar radiation can now be outputted if required, with the option to undertake a more intensive calculation of the UV wavelengths if desired.

Finally, the model output now includes the snow temperature profiles in the sun and the shade (sunsnow and shadsnow) as well as plant outputs from Campbell's Program 11.1 (transpiration rate, leaf and root water potentials in the output matrices plant and shadplant).