Higher daytime skin temperature in rural areas

[YuanSUN]

Hi all,

I ran WRF-Noah-LSM and WRF-CTSM at 1.2 km spatial resolution.

The plot (a) show higher skin temperature in the west and south than in the city center. Is it normal? How to explain it?

I also found such patterns in https://doi.org/10.1002/2018JD028377.

Thanks for any comments.

Best,
Yuan

 

[Ming Chen]

Have you looked at landuse type over those areas with higher skin temperature? Also, what is the vegetation fraction over central urban area? Is it larger than that over areas of higher skin temperature? How about surface air temperature and humidity (T2 and Q2)?

 

[YuanSUN]

Have you looked at landuse type over those areas with higher skin temperature? Also, what is the vegetation fraction over central urban area? Is it larger than that over areas of higher skin temperature? How about surface air temperature and humidity (T2 and Q2)?

Dear Ming,

Thanks for taking the time.

The land use at the southwest corner is mainly cropland.


The vegetation fraction is below. For urban grid cells, FRC_URB is 0.9. So 1-FRC_URBAN = 0.1 for natural landscape (vegetation and bare soil) for urban grid cells.



T2 (unit: °C) and Q2 (unit: g/kg) look normal.



I am still seeking the cause and find that some previous studies also reported higher LSTs outside urban areas, for example, Redirecting.

I also found that in a case study of Beijing, cropland and urban areas had similar LST as: "Tskin values include all-urban-pixel-averaged Beijing area (306 K), cropland (304 K)". https://doi.org/10.1155/2010/681587

I am not sure if I could explain it based on this evidence. Look forward to hearing from you. Thanks!

Best,
Yuan

 

[Ming Chen]

Yuan,
I don't have an immediate answer to your question. I will discuss this issue with our expert and get back to you ....