冷却屋顶对北京城市热环境影响的模拟研究
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摘要
两种类型冷却屋顶(高反照率屋顶、绿色屋顶)的研究对于北京夏季城市高温的缓解作用具有重要的意义。耦合单层城市冠层模式(SLUCM)与天气研究与预报(WRF3.8)模式,采用北京市及其外围地区158个站点气象资料评估模式对照案例(case1)的模拟性能,并选取7组不同反照率屋顶案例(case2—4)和不同覆盖比例的绿色屋顶案例(case5—8)进行敏感性试验。研究结果表明:(1)在北京城市区域,高反照率为0.85的屋顶(case4)比绿色占比100%的屋顶(case8)具有更好的降温效果,case4的3 d平均降温可达到0.90℃,而case8降温为0.46℃。(2)屋顶反照率每增加0.1,会导致北京城市区域最高气温降低0.27℃;绿色屋顶比例的增大也会导致温度的降低,每增加10%,最高气温降低0.16℃。(3)两种冷却屋顶对城市热岛也存在显著的影响,在13—14时(北京时),case4与case1对比的城市热岛(UHI)降温最大差值为1.47℃,比case8的城市热岛降温更加明显。(4)在城市区域垂直高度上,冷却屋顶的降温作用可达到1.2 km,同时湍流运动存在明显的减弱;在3 d的12—18时,case4、case8与case1对比,边界层高度平均降低了669与430 m。
The study of two types of cooling roofs(high reflectivity roofs and green roofs) has important implications for the mitigation of high temperature in the summer in Beijing. This paper has implemented the Weather Research and Forecasting Model(WRF3.8) coupled with the Single-Layer City Canopy Model(SLUCM) to evaluate the simulation performance of the control case(case1) by this coupled model using meteorological data collected at 158 stations in Beijing. Seven cases with roofs of different albedos(cases2-4) and green roofs with different cover ratios(cases5-8) are conducted for sensitivity studies. The results of the study show that:(1) in the urban area of Beijing, the roof whose albedo is 0.85(case4) has a better cooling effect than the 100%(case8) green roof, the average temperature in case4 drops by 0.90℃ and the cooling in case 8 is 0.46℃;(2) with the albedo increase of 0.1 in the roof, the maximum temperature in Beijing will decrease by 0.27℃. And the increase in the proportion of green roofs will also result in a decrease in temperature. With every 10% increase in the green roof, the maximum temperature will decrease by 0.16℃;(3) the two types of cooling roofs have significant impacts on the urban heat island(UHI). Compared with case1, the maximum UHI in case4 drops by 1.47℃ during the daytime from 13:00 BT to 14:00 BT, which is higher than the cooling effect shown in case8;(4) the cooling effect of the cooling roofs can reach 1.2 km height above the city, and the turbulence is also significantly reduced. During 12:00-18:00 BT of the three days, compared with case1, the height of the planetary boundary layer in case4 and case8 on average are reduced by 669 and 430 m, respectively.
The study of two types of cooling roofs(high reflectivity roofs and green roofs) has important implications for the mitigation of high temperature in the summer in Beijing. This paper has implemented the Weather Research and Forecasting Model(WRF3.8) coupled with the Single-Layer City Canopy Model(SLUCM) to evaluate the simulation performance of the control case(case1) by this coupled model using meteorological data collected at 158 stations in Beijing. Seven cases with roofs of different albedos(cases2-4) and green roofs with different cover ratios(cases5-8) are conducted for sensitivity studies. The results of the study show that:(1) in the urban area of Beijing, the roof whose albedo is 0.85(case4) has a better cooling effect than the 100%(case8) green roof, the average temperature in case4 drops by 0.90℃ and the cooling in case 8 is 0.46℃;(2) with the albedo increase of 0.1 in the roof, the maximum temperature in Beijing will decrease by 0.27℃. And the increase in the proportion of green roofs will also result in a decrease in temperature. With every 10% increase in the green roof, the maximum temperature will decrease by 0.16℃;(3) the two types of cooling roofs have significant impacts on the urban heat island(UHI). Compared with case1, the maximum UHI in case4 drops by 1.47℃ during the daytime from 13:00 BT to 14:00 BT, which is higher than the cooling effect shown in case8;(4) the cooling effect of the cooling roofs can reach 1.2 km height above the city, and the turbulence is also significantly reduced. During 12:00-18:00 BT of the three days, compared with case1, the height of the planetary boundary layer in case4 and case8 on average are reduced by 669 and 430 m, respectively.
引文
王正兴, 江玉华, 李炬等. 2009. 在北京气象铁塔上测量城市边界层辐射的研究. 高原气象, 28(1): 20-27. Wang Z X, Jiang Y H, Li J, et al. 2009. Study on measurement of urban boundary layer radiation on the meteorological tower in Beijing. Plateau Meteor, 28(1): 20-27
伍见军, 王咏薇, 朱彬等. 2013. WRF模式中城市冠层参数化方案在重庆气象环境模拟中的性能比较. 长江流域资源与环境, 22(12): 1627-1634. Wu J J, Wang Y W, Zhu B, et al. 2013. Performance comparison of different urban canopy schemes in WRF model under Chongqing meteorological simulation. Resour Environ Yangtze Basin, 22(12): 1627-1634 (in Chinese)
Akbari H, Damon Matthews H, Seto D. 2012. The long-term effect of increasing the albedo of urban areas. Environ Res Lett, 7(2): 024004
Chen F, Dudhia J. 2001. Coupling an aAdvanced land surface-hydrology model with the Penn State-NCAR MM5 modeling system. Part Ⅰ: Model implementation and sensitivity. Mon Wea Rev, 129(4): 569-585
Ching J K S. 2013. A perspective on urban canopy layer modeling for weather, climate and air quality applications. Urban Climate, 3: 13-39
Dudhia J. 1989. Numerical study of convection observed during the winter monsoon experiment using a mesoscale two-dimensional model. J Atmos Sci, 46(20): 3077-3107
Dvorak B, Volder A. 2010. Green roof vegetation for North American ecoregions: A literature review. Landsc Urban Plan, 96(4): 197-213
Georgescu M, Morefield P E, Bierwagen B G, et al. 2014. Urban adaptation can roll back warming of emerging megapolitan regions. Proc Natl Acad Sci U S A, 111(8): 2909-2914
Hong S Y, Dudhia J, Chen S H. 2004. A revised approach to ice microphysical processes for the bulk parameterization of clouds and precipitation. Mon Wea Rev, 132(1): 103-120
Hou A Z, Ni G H, Yang H B, et al. 2013. Numerical analysis on the contribution of urbanization to wind stilling: An example over the greater Beijing metropolitan area. J Appl Meteor Climatol, 52(5): 1105-1115
Jacobson M Z, Ten Hoeve J E. 2012. Effects of urban surfaces and white roofs on global and regional climate. J Climate, 25(3): 1028-1044
. The Surface Layer Parameterization in the NCEP Eta Model. Geneva, Switzerland: World Meteorological Organization
Kovats R S, Hajat S. 2008. Heat stress and public health:A critical review. Ann Rev Pub Health, 29: 41-55
Li D, Bou-Zeid E. 2013. Synergistic interactions between urban heat islands and heat waves:The impact in cities is larger than the sum of its parts. J Appl Meteor Climatol, 52(9): 2051-2064
Li D, Bou-Zeid E, Oppenheimer M. 2014. The effectiveness of cool and green roofs as urban heat island mitigation strategies. Environ Res Lett, 9(5): 055002
Miao S G, Chen F, LeMone M A, et al. 2009. An observational and modeling study of characteristics of urban heat island and boundary layer structures in Beijing. J Appl Meteor Climatol, 48(3): 484-501
Miao S G, Chen F. 2014. Enhanced modeling of latent heat flux from urban surfaces in the Noah/single-layer urban canopy coupled model. Sci China Earth Sci, 57(10): 2408-2416
Millstein D, Menon S. 2011. Regional climate consequences of large-scale cool roof and photovoltaic array deployment. Environ Res Lett, 6(3): 034001
Mlawer E J, Taubman S J, Brown P D, et al. 1997. Radiative transfer for inhomogeneous atmospheres: RRTM, a validated correlated-k model for the longwave. J Geophys Res, 102(D14): 16663-16682
Northridge M E, Sclar E. 2003. A joint urban planning and public health framework: Contributions to health impact assessment. Am J Pub Health, 93(1): 118-121
Qiu G Y, Li H Y, Zhang Q T, et al. 2013. Effects of evapotranspiration on mitigation of urban temperature by vegetation and urban agriculture. J Integr Agric, 12(8): 1307-1315
Rizwan A M, Dennis L Y C, Liu C. 2008. A review on the generation, determination and mitigation of Urban Heat Island. J Environ Sci, 20(1): 120-128
Rowe D B. 2011. Green roofs as a means of pollution abatement. Environ Pollut, 159(8-9): 2100-2110
Saadatian O, Sopian K, Salleh E. 2013. A review of energy aspects of green roofs. Renew Sust Energy Rev, 23: 155-168
Santamouris M. 2014. Cooling the cities-a review of reflective and green roof mitigation technologies to fight heat island and improve comfort in urban environments. Sol Energy, 103: 682-703
Sharma A, Conry P, Fernando H J S, et al. 2016. Green and cool roofs to mitigate urban heat island effects in the Chicago metropolitan area: Evaluation with a regional climate model. Environ Res Lett, 11(6): 064004
Smith K R, Roebber P J. 2011. Green roof mitigation potential for a proxy future climate scenario in Chicago, Illinois. J Appl Meteor Climatol, 50(3): 507-522
Sun T, Grimmond C S B, Ni G H. 2016. How do green roofs mitigate urban thermal stress under heat waves?. J Geophys Res Atmos, 121(10): 5320-5335
United Nations. 2007. World urbanization prospects: The 2007 revision.
Wang X Q, Gong Y B. 2010. The impact of an urban dry island on the summer heat wave and sultry weather in Beijing city. Chinese Sci Bull, 55(16): 1657-1661
Wong E, Akbari H, Bell R, et al. 2011. Reducing urban heat islands: Compendium of strategies. Washington: Environmental Protection Agency
Wu J Y, Zhou Y, Gao Y, et al. 2014. Estimation and uncertainty analysis of impacts of future heat waves on mortality in the eastern United States. Environ Health Perspect, 122(1): 10-16
伍见军, 王咏薇, 朱彬等. 2013. WRF模式中城市冠层参数化方案在重庆气象环境模拟中的性能比较. 长江流域资源与环境, 22(12): 1627-1634. Wu J J, Wang Y W, Zhu B, et al. 2013. Performance comparison of different urban canopy schemes in WRF model under Chongqing meteorological simulation. Resour Environ Yangtze Basin, 22(12): 1627-1634 (in Chinese)
Akbari H, Damon Matthews H, Seto D. 2012. The long-term effect of increasing the albedo of urban areas. Environ Res Lett, 7(2): 024004
Chen F, Dudhia J. 2001. Coupling an aAdvanced land surface-hydrology model with the Penn State-NCAR MM5 modeling system. Part Ⅰ: Model implementation and sensitivity. Mon Wea Rev, 129(4): 569-585
Ching J K S. 2013. A perspective on urban canopy layer modeling for weather, climate and air quality applications. Urban Climate, 3: 13-39
Dudhia J. 1989. Numerical study of convection observed during the winter monsoon experiment using a mesoscale two-dimensional model. J Atmos Sci, 46(20): 3077-3107
Dvorak B, Volder A. 2010. Green roof vegetation for North American ecoregions: A literature review. Landsc Urban Plan, 96(4): 197-213
Georgescu M, Morefield P E, Bierwagen B G, et al. 2014. Urban adaptation can roll back warming of emerging megapolitan regions. Proc Natl Acad Sci U S A, 111(8): 2909-2914
Hong S Y, Dudhia J, Chen S H. 2004. A revised approach to ice microphysical processes for the bulk parameterization of clouds and precipitation. Mon Wea Rev, 132(1): 103-120
Hou A Z, Ni G H, Yang H B, et al. 2013. Numerical analysis on the contribution of urbanization to wind stilling: An example over the greater Beijing metropolitan area. J Appl Meteor Climatol, 52(5): 1105-1115
Jacobson M Z, Ten Hoeve J E. 2012. Effects of urban surfaces and white roofs on global and regional climate. J Climate, 25(3): 1028-1044
. The Surface Layer Parameterization in the NCEP Eta Model. Geneva, Switzerland: World Meteorological Organization
Kovats R S, Hajat S. 2008. Heat stress and public health:A critical review. Ann Rev Pub Health, 29: 41-55
Li D, Bou-Zeid E. 2013. Synergistic interactions between urban heat islands and heat waves:The impact in cities is larger than the sum of its parts. J Appl Meteor Climatol, 52(9): 2051-2064
Li D, Bou-Zeid E, Oppenheimer M. 2014. The effectiveness of cool and green roofs as urban heat island mitigation strategies. Environ Res Lett, 9(5): 055002
Miao S G, Chen F, LeMone M A, et al. 2009. An observational and modeling study of characteristics of urban heat island and boundary layer structures in Beijing. J Appl Meteor Climatol, 48(3): 484-501
Miao S G, Chen F. 2014. Enhanced modeling of latent heat flux from urban surfaces in the Noah/single-layer urban canopy coupled model. Sci China Earth Sci, 57(10): 2408-2416
Millstein D, Menon S. 2011. Regional climate consequences of large-scale cool roof and photovoltaic array deployment. Environ Res Lett, 6(3): 034001
Mlawer E J, Taubman S J, Brown P D, et al. 1997. Radiative transfer for inhomogeneous atmospheres: RRTM, a validated correlated-k model for the longwave. J Geophys Res, 102(D14): 16663-16682
Northridge M E, Sclar E. 2003. A joint urban planning and public health framework: Contributions to health impact assessment. Am J Pub Health, 93(1): 118-121
Qiu G Y, Li H Y, Zhang Q T, et al. 2013. Effects of evapotranspiration on mitigation of urban temperature by vegetation and urban agriculture. J Integr Agric, 12(8): 1307-1315
Rizwan A M, Dennis L Y C, Liu C. 2008. A review on the generation, determination and mitigation of Urban Heat Island. J Environ Sci, 20(1): 120-128
Rowe D B. 2011. Green roofs as a means of pollution abatement. Environ Pollut, 159(8-9): 2100-2110
Saadatian O, Sopian K, Salleh E. 2013. A review of energy aspects of green roofs. Renew Sust Energy Rev, 23: 155-168
Santamouris M. 2014. Cooling the cities-a review of reflective and green roof mitigation technologies to fight heat island and improve comfort in urban environments. Sol Energy, 103: 682-703
Sharma A, Conry P, Fernando H J S, et al. 2016. Green and cool roofs to mitigate urban heat island effects in the Chicago metropolitan area: Evaluation with a regional climate model. Environ Res Lett, 11(6): 064004
Smith K R, Roebber P J. 2011. Green roof mitigation potential for a proxy future climate scenario in Chicago, Illinois. J Appl Meteor Climatol, 50(3): 507-522
Sun T, Grimmond C S B, Ni G H. 2016. How do green roofs mitigate urban thermal stress under heat waves?. J Geophys Res Atmos, 121(10): 5320-5335
United Nations. 2007. World urbanization prospects: The 2007 revision.
Wang X Q, Gong Y B. 2010. The impact of an urban dry island on the summer heat wave and sultry weather in Beijing city. Chinese Sci Bull, 55(16): 1657-1661
Wong E, Akbari H, Bell R, et al. 2011. Reducing urban heat islands: Compendium of strategies. Washington: Environmental Protection Agency
Wu J Y, Zhou Y, Gao Y, et al. 2014. Estimation and uncertainty analysis of impacts of future heat waves on mortality in the eastern United States. Environ Health Perspect, 122(1): 10-16