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AC Consumption and Temperature

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htan2013

Member
Dear all WRF users,

I tried to run 3 experiments including a Control experiment, a Cool Roof experiment (change albedo to 0.8), and a Green Roof experiment over an Urban area using WRF4.3.

When I plotted the skin temperature/2-m temperature, I noticed that the cool roof had a more cooling effect than the green roof, which makes sense. But when I plot ac consumption (Varname: CM_AC_URB3), the green roof experiment has less AC consumption than the cool roof, which does not make sense since the green roof experiment is warmer than the cool roof experiment. All urban parameters about AC in URBPARAM.tbl are the same in two sensitivity experiments.

I am wondering why the green roof experiment is warmer over the urban areas than the cool roof, and in the meantime, the green roof has more AC consumption savings than the cool roof? What temperature variables are related to the AC consumption in WRF? Is it like indoor temperature (TLEV_URB3D) or some building temperature variable?

Best regards,
Haochen
 
Haochen,
I don't have an immediate answer to your question. Your results may indicate that either something is physically wrong in the urban scheme, or the parameters surrounding the scheme are not correctly specified. One issue is that, the values specified in URBPARM.tbl are based on specific cases, and they may not applied everywhere. Another issue is, we need to determine AC consumption depends on what processes and parameters in the scheme. Would you please read the two papers I listed below and hopefully you can fid some helpful information:

Salamanca, F., and A. Martilli, 2010: A new building energy model coupled with an urban canopy parameterization for urban climate simulations––part II. Validation with one dimension off–line simulations. Theor. Appl. Climatol., 99, 345–356.
doi:10.1007/s00704-009-0143-8

Martilli A, Clappier A, and Rotach M.W., 2002: An urban surface exchange parameterization for mesoscale models. Bound.-Layer Meteorol., 104, 261–304.
doi:10.1023/A:1016099921195
 
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