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I am developing a simple parameterisation scheme script to predict surface temperature.

The script calculates six heat fluxes including sensible heat flux using a resistance to heat flux parameter. The literature I've checked describes resistance to heat flux as taking values greater than 0 and having units of $\rm{s} ~ \rm{m}^{-1}$.

Sensible heat flux is calculated as,

$Q_H = \frac{\rho c_p \Delta T}{r_H}$,

where $\rho$ is air density, $c_p$ is specific heat at constant pressure, $\Delta T$ is change in temperature between the ground layer and the surface layer and $r_H$ is resistance to heat flux.

What is a reasonable range of values for resistance to heat flux in meteorology?

A single range would be useful but ranges for urban, agricultural, forest, desert, mountain and marine areas would be preferable.

Additionally, I'm open to alternative suggestions for calculating sensible heat flux but using x % of solar radiation feels overly simple.

For context:

My script is currently predicting day time temperatures which are probably too low and night time temperatures which are probably too high. I'd like to verify that the sensible heat flux calculation is the cause but I need to know what reasonable values for resistance to heat flux are.

This is based on the second chapter of David Stensrud's Parameterisation Schemes book and is inspired by Luke Madaus' blog post, Digging into a "simple" weather model.

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  • $\begingroup$ In my answer below I provide a range of values in urban canyons. I will upvote answers which provide ranges for other environments. And will accept the first answer which provides ranges for multiple environments. $\endgroup$ – makeyourownmaker Nov 28 '19 at 16:44
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Alec Bennett calculates resistance to heat flux values in an urban canyon as part of his MSc in meteorology dissertation: Heat Fluxes from Street Canyons.

The calculated values range from 76.6 to 84.2 and are based on measurements taken on May 18th and 19th 2004 from 08:00 to 17:00 (both days).

See the two tables in the Appendix on page 68 for the full range of values.

I have not read the entire thesis. It's unclear to me what confidence I should place in these values.

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  • $\begingroup$ Will rural, desert, mountain, marine etc environments have higher or lower values? How much higher/lower should they be? $\endgroup$ – makeyourownmaker Nov 28 '19 at 21:24

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