Sains Malaysiana 45(5)(2016): 689–697

Horizontal Heat Flux between Urban Buildings and Soil and Its Influencing Factors

(Fluks Haba Mendatar antara Bangunan Bandar dan Tanah serta Faktor yang Mempengaruhinya)

HONGXUAN ZHOU, XIAOLIN WANG, YUANZHENG LI, FENGSEN HAN & DAN HU*

State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China

Received: 12 June 2015/Accepted: 3 December 2015

ABSTRACT

The soil temperature near four external walls with different orientations was investigated in spring and summer. In both seasons, the soil temperature was higher in the positions closest to the buildings, suggesting that the buildings were a heat source for the soil surrounding them. Therefore, it could be confirmed that there was lateral heat transfer between the soil and the buildings. Based on this, a soil heat flux plate was set between the soil and the buildings to investigate the horizontal heat flux. The data showed diurnal variations of the horizontal heat flux in both spring and summer. In order to determine the factors that influenced the horizontal heat flux and to provide a basis to understand its mechanism, the correlations between the data of several meteorological factors and the horizontal heat flux were analysed. The results showed that solar radiation was significantly correlated with the horizontal heat flux (p<0.0001) in any single season and in the two seasons that were studied. Additionally, other meteorological factors (net radiation, air temperature, relative humidity and soil temperature and moisture) showed strong correlations with the horizontal heat flux on a diurnal scale only. On a seasonal time scale, the correlation might be significant (p<0.0001) as well, but the correlation coefficients decreased too significantly, such as those for soil temperature, air temperature and relative humidity. Alternatively, the correlation might not be significant (p>0.05), such as that for soil moisture. The stepwise regression results indicated that the relative importance of these meteorological factors was 48.63, 21.94, 14.44, 8.12 and 6.87% for solar radiation, soil temperature, air temperature, relative humidity and soil moisture, respectively, on a diurnal scale.

Keywords: Building; construction; horizontal heat flux; soil temperature; urban area

ABSTRAK

Suhu tanah berhampiran empat dinding luar dengan orientasi yang berbeza telah dikaji pada musim bunga dan musim panas. Dalam kedua-dua musim, suhu tanah adalah lebih tinggi dalam kedudukan paling hampir dengan bangunan, menunjukkan bahawa bangunan adalah sumber haba untuk tanah di sekeliling mereka. Oleh itu, ia boleh mengesahkan terdapat pemindahan haba sisi antara tanah dan bangunan. Berdasarkan ini, plat fluks haba tanah telah ditubuhkan antara tanah dan bangunan untuk mengkaji fluks haba mendatar. Data menunjukkan variasi diurnal fluks haba mendatar dalam kedua-dua musim bunga dan musim panas. Untuk menentukan faktor yang mempengaruhi fluks haba mendatar dan untuk menyediakan asas untuk memahami mekanismenya, korelasi antara data daripada beberapa faktor meteorologi dan fluks haba mendatar telah dianalisis. Hasil kajian menunjukkan bahawa sinaran suria telah mempunyai hubungan yang signifikan dengan fluks haba mendatar (p<0.0001) dalam mana-mana musim tunggal dan dalam dua musim yang dikaji. Selain itu, faktor meteorologi lain (sinaran bersih, suhu udara, kelembapan dan suhu tanah dan kelembapan) menunjukkan korelasi yang kuat dengan fluks haba mendatar pada skala yang diurnal sahaja. Pada skala masa bermusim, korelasi mungkin signifikan (p<0.0001) juga, tetapi pekali korelasi menurun terlalu ketara, seperti yang untuk suhu tanah, suhu udara dan kelembapan relatif. Sebagai alternatif, korelasi mungkin tidak signifikan (p>0.05), seperti untuk kelembapan tanah. Keputusan regresi ikut langkah menunjukkan bahawa kepentingan relatif faktor meteorologi adalah 48,63, 21,94, 14,44, 8.12 dan 6.87% masing-masing untuk radiasi solar, suhu tanah, suhu udara, kelembapan dan kelembapan tanah pada skala yang diurnal.

Kata kunci: Fluks haba mendatar; kawasan bandar; pembinaan; suhu tanah

REFERENCES

Bogren, J. & Gustavsson, T. 1991. Nocturnal air and road surface temperature variations in complex terrain. International Journal of Climatology 11(4): 443-455.

Chen, Y., Zhou, H., Zhang, H., Du, G. & Zhou, J. 2015. Urban flood risk warning under rapid urbanization. Environmental Research 139: 3-10.

Delgado, J.D., Arroyo, N.L., Arévalo, J.R. & Fernández-Palacios, J.M. 2007. Edge effects of roads on temperature, light, canopy cover, and canopy height in laurel and pine forests (Tenerife, Canary Islands). Landscape and Urban Planning 81(4): 328-340.

Dos Santos, G.H. & Mendes, N. 2006. Simultaneous heat and moisture transfer in soils combined with building simulation. Energy and Buildings 38(4): 303-314.

Fan, Y., Sheng, W., Du, L. & Feng, Z. 2008. Comparison and analysis of temperature on various underlying surfaces in summer. Atmospheric Science Research and Application 31(2): 43-51.

Halverson, H.G. & Heisler, G.M. 1981. Soil temperatures under urban trees and asphalt. United States Department of Agriculture, Forest Service Research Paper NE-481.

Horton, R. & Wierenga, P.J. 1983. Estimating the soil heat flux from observations of soil temperature near the surface. Soil Science Society of America Journal 47(1): 14-20.

Huang, H., Dong, H., Ling, Y. & Li, X. 2003. Characteristic analysis and prediction of temperarure on different underlying surfaces in summer in Nanning. Meteorological Science and Technology 31(4): 253-256.

Idso, S.B., Aase, J.K. & Jackson, R.D. 1975. Net radiation-soil heat flux relations as influenced by soil water content variations. Boundary-Layer Meteorology 9(1): 113-122.

Kustas, W.P., Prueger, J.H., Hatfield, J.L., Ramalingam, K. & Hipps, L.E. 2000. Variability in soil heat flux from a mesquite dune site. Agricultural and Forest Meteorology 103(3): 249-264.

Kustas, W.P. & Daughtry, C.S.T. 1990. Estimation of the soil heat flux/net radiation ratio from spectral data. Agricultural and Forest Meteorology 49(3): 205-223.

Landman, K.A. & Delsante, A.E. 1987. Steady-state heat losses from a building floor slab with horizontal edge insulation. Building and Environment 22(1): 57-60.

Landsberg, H.E. 1981. The Urban Climate. International Geophysics Series, Vol. 28. New York: Academic Press. p. 275.

Liu, C., Shi, B., Tang, C. & Gao, L. 2011. A numerical and field investigation of underground temperatures under Urban Heat Island. Building and Environment 46(5): 1205-1210.

Mihalakakou, G., Santamouris, M., Asimakopoulos, D. & Argiriou, A. 1995. On the ground temperature below buildings. Solar energy 55(5): 355-362.

Norman, J.M., Kustas, W.P. & Humes, K.S. 1995. Source approach for estimating soil and vegetation energy fluxes in observations of directional radiometric surface temperature. Agricultural and Forest Meteorology 77(3): 263-293.

Oke, T.R. 1982. The energetic basis of the urban heat island. Quarterly Journal of the Royal Meteorological Society 108(455): 1-24.

Pang, J. 1979. A climatology calculation method for ten-day total solar radiation. Meteorology 2: 20-21.

Pickett, S.T.A., Cadenasso, M.L., Grove, J.M., Nilon, C.H., Pouyat, R.V., Zipperer, W.C. & Costanza, R. 2008. Urban ecological systems: Linking terrestrial ecological, physical, and socioeconomic components of metropolitan areas. In Urban Ecology. New York: Springer.

Qu, N. 2001. Building envelope heat transfer simulation under the natural climate condition in heating region. China Academy of Building Research.

Rees, S.W., Adjali, M.H., Zhou, Z., Davies, M. & Thomas, H.R. 2000. Ground heat transfer effects on the thermal performance of earth-contact structures. Renewable and Sustainable Energy Reviews 4(3): 213-265.

Santanello Jr., J.A. & Friedl, M.A. 2003. Diurnal covariation in soil heat flux and net radiation. Journal of Applied Meteorology 42(6): 851-862.

Shao, M.A., Wang, Q.J. & Huang, M.B. 2006. Soil Physics. Beijing: Higher Education Press. p.16-21.

Shi, B., Tang, C.S., Liu, C. & Jiang, H.T. 2012. Differences in shallow soil temperatures at urban and rural areas. Journal of Engineering Geology 20(1): 58-65.

Sun, C., Jiang, H., Liu, Y., Tan, Y. & Zhang, J. 2014. Variation of soil heat flux in the phyllostachys edulis forest in Anji during the growing season. Chinese Journal of Soil Science 3: 590-594.

Tang, C.S., Shi, B., Gao, L., Daniels, J.L., Jiang, H.T. & Liu, C. 2011. Urbanization effect on soil temperature in Nanjing, China. Energy and Buildings 43(11): 3090-3098.

Turkoglu, N. 2010. Analysis of urban effects on soil temperature in Ankara. Environmental Monitoring and Assessment 169(1- 4): 439-450.

Wei, C., Wang, L., Liu, X., Zhao, X. & Liu, S. 2014. Soil heat fluxes of Larix gmelinii in Daxing’anling of Heilongjiang province. Protection Forest Science and Technology 5: 5-7.

Yang, J.H. 2006. The influence of highway soil to the growth of plant and its improvement measures. Hebei Jiaotong Science and Technology 2: 49-52.

Zhang, J., Liang, H., Jiang, X., Yang, Y. & Chen, G. 2008. The summer temperature characteristics on diferent underlying surfaces in Shenyang and application to meteorologic services. Scientia Meteorologica Sinica 28(5): 528-532.

Zhou, L., Dickinson, R.E., Tian, Y., Fang, J., Li, Q., Kaufmann, R.K., Tucker, C.J. & Myneni, R.B. 2004. Evidence for a significant urbanization effect on climate in China. Proceedings of the National Academy of Sciences of the United States of America 101(26): 9540-9544.

Zhou, S., Zhang, R. & Zhang, C. 1997. Meteorology and Climatology. Vol. 5: People’s Education Press.

*Corresponding author; email: hudan@rcees.ac.cn