Observations of urban boundary layer structure during a strong urban heat island event
详细信息 查看全文
- 作者：J. F. Barlow ; C. H. Halios ; S. E. Lane ; C. R. Wood
- 关键词：Urban boundary layer ; Doppler lidar ; Urban heat island ; Turbulence profiles
- 刊名：Environmental Fluid Mechanics
- 出版年：2015
- 出版时间：April 2015
- 年：2015
- 卷：15
- 期：2
- 页码：373-398
- 全文大小：4,248 KB
- 参考文献：1. Mestayer, PG, Durand, P, Augustin, P (2005) The urban boundary-layer field campaign in Marseille (UBL/CLU-ESCOMPTE): set-up and first results. Bound Layer Meteorol 114: pp. 315-365 CrossRef
2. Masson, V, Gomes, L, Pigeon, G (2008) The canopy and aerosol particles interactions in Toulouse urban layer (CAPITOUL) experiment. Meteorol Atmos Phys 102: pp. 135-157 CrossRef
3. Pal, S, Xuref-Remy, I, Ammoura, L (2012) Spatio-temporal variability of the atmospheric boundary layer depth over the Paris agglomeration: an assessment of the impact of the urban heat island intensity. Atmos Environ 63: pp. 261-275 CrossRef
4. Kallistratova, MA, Kouznetsov, RD (2011) Low-level jets in the Moscow region in summer and winter observed with a sodar network. Bound Layer Meteorol 143: pp. 159-175 CrossRef
5. Wang, Y, Klipp, C, Garvey, DM, Ligon, DA, Williamson, CC, Chang, SS, Newsom, RK, Calhoun, R (2007) Nocturnal low-level-jet-dominated boundary layer observed by a Doppler lidar over Oklahoma City during JU2003. J Appl Meteorol Climatol 46: pp. 2098-2109 CrossRef
6. Lundquist, JK, Mirocha, JD (2008) Interaction of nocturnal low-level jets with urban geometries as seen in Joint Urban 2003 data. J Appl Meteorol Climatol 47: pp. 44-58 CrossRef
7. Roth, M (2000) Review of atmospheric turbulence over cities. Q J R Meteorol Soc 126: pp. 941-990 CrossRef
8. Barlow, JF, Dunbar, TM, Nemitz, EG, Wood, CR, Gallagher, MW, Davies, F, O’Connor, E, Harrison, RM (2011) Boundary layer dynamics over London, UK, as observed using Doppler lidar during REPARTEE-II. Atmos Chem Phys 11: pp. 2111-2125 CrossRef
9. Seibert, P, Geyrich, F, Gryning, SE, Joffre, S, Rasmussen, A, Tercier, P (2000) Review and intercomparison of operational methods for the determination of the mixing height. Atmos Environ 34: pp. 1001-1027 CrossRef
10. Emeis, S, Sch?fer, K, Münkel, C (2008) Surface-based remote sensing of the mixing-layer height: a review. Meteorol Z 17: pp. 621-630 CrossRef
11. Otkin, JA, Hartung, DC, Turner, DD (2011) Assimilation of surface-based boundary layer profiler observations during a cool-season weather event using an observing system simulation experiment. Part I: analysis impact. Mon Weather Rev 139: pp. 2309-2326 CrossRef
12. Collier, CG, Davies, F, Bozier, KE, Holt, AR, Middleton, DR, Pearson, GN, Siemen, S, Willetts, DV, Upton, GJG, Young, RI (2005) Dual-Doppler lidar measurements for improving dispersion models. B Am Meteorol Soc 86: pp. 825-838 CrossRef
13. Calhoun, R, Heap, R, Princevac, M, Newsom, R, Fernando, H, Ligon, D (2006) Virtual towers using coherent Doppler lidar during the Joint Urban 2003 dispersion experiment. J Appl Meteorol Climatol 45: pp. 1116-1126 CrossRef
14. Wood, CR, Lacser, A, Barlow, JF, Padhra, A, Belcher, SE, Nemitz, E, Helfter, C, Famulari, D, Grimmond, CSB (2010) Turbulent flow at 190 m above London during 2006-008: a climatology and the applicability of similarity theory. Bound Layer Meteorol 137: pp. 77-96 CrossRef
15. Helfter, C, Famulari, D, Phillips, GJ, Barlow, JF, Wood, CR, Grimmond, CSB, Nemitz, E (2011) Controls of carbon dioxide concentrations and fluxes above central London. Amos Chem Phys 11: pp. 1913-1928
16. Lane, SE, Barlow, JF, Wood, CR (2013) An assessment of - 刊物类别：Earth and Environmental Science
- 刊物主题：Environment
Environmental Physics
Mechanics
Hydrogeology
Meteorology and Climatology
Oceanography - 出版者：Springer Netherlands
- ISSN：1573-1510
文摘
It has long been known that the urban surface energy balance is different to that of a rural surface, and that heating of the urban surface after sunset gives rise to the Urban Heat Island (UHI). Less well known is how flow and turbulence structure above the urban surface are changed during different phases of the urban boundary layer (UBL). This paper presents new observations above both an urban and rural surface and investigates how much UBL structure deviates from classical behaviour. A 5-day, low wind, cloudless, high pressure period over London, UK, was chosen for analysis, during which there was a strong UHI. Boundary layer evolution for both sites was determined by the diurnal cycle in sensible heat flux, with an extended decay period of approximately 4?h for the convective UBL. This is referred to as the “Urban Convective Island-as the surrounding rural area was already stable at this time. Mixing height magnitude depended on the combination of regional temperature profiles and surface temperature. Given the daytime UHI intensity of \(1.5\,^\circ \mathrm{C}\) , combined with multiple inversions in the temperature profile, urban and rural mixing heights underwent opposite trends over the period, resulting in a factor of three height difference by the fifth day. Nocturnal jets undergoing inertial oscillations were observed aloft in the urban wind profile as soon as the rural boundary layer became stable: clear jet maxima over the urban surface only emerged once the UBL had become stable. This was due to mixing during the Urban Convective Island reducing shear. Analysis of turbulent moments (variance, skewness and kurtosis) showed “upside-down-boundary layer characteristics on some mornings during initial rapid growth of the convective UBL. During the “Urban Convective Island-phase, turbulence structure still resembled a classical convective boundary layer but with some influence from shear aloft, depending on jet strength. These results demonstrate that appropriate choice of Doppler lidar scan patterns can give detailed profiles of UBL flow. Insights drawn from the observations have implications for accuracy of boundary conditions when simulating urban flow and dispersion, as the UBL is clearly the result of processes driven not only by local surface conditions but also regional atmospheric structure.