ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-11-6297-2011 Atmospheric boundary layer characteristics over the Pearl River Delta, China, during the summer of 2006: measurement and model results Fan S. J. 1 Fan Q. 1 Yu W. 1 Luo X. Y. 1 Wang B. M. 1 Song L. L. 2 Leong K. L. 3 Department of Atmospheric Sciences, Sun yat-sen University, Guangzhou, 510275, China Climate Center of Guangdong Province, Guangzhou, 510080, China Macao Meteorological and Geophysical Bureaus, Macao, China 04 07 2011 11 13 6297 6310 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/11/6297/2011/acp-11-6297-2011.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/11/6297/2011/acp-11-6297-2011.pdf

As part of the PRIDE-PRD2006 intensive campaign, atmospheric boundary layer (ABL) measurements were performed in Qingyuan, Panyu, and Xinken over the Pearl River Delta (PRD) on 1–30 July 2006. During the summer, the surface winds over the PRD are generally controlled by the south, usually with vertical wind shear at a height of approximately 800 m. Subsidence and precipitation from a tropical cyclone affects the air quality of the PRD. Under subsidence, wind speed in the ABL and the height of the ABL decrease and result in high-level concentrations. When the background wind speed is small or calm, the wind profile in Panyu and Xinken changes dramatically with height, which is perhaps caused by local circulation, such as sea-land breezes. To better understand the ABL of the PRD, simulations that used the Weather Research and Forecasting (WRF) mesoscale model were utilized to analyze the ABL characteristics over the PRD. Based on three types of weather condition simulations (i.e., subsidence days, rainy days, and sunny days), the WRF model revealed that the simulated temperature and wind fields in these three cases were moderately consistent with the measurements. The results showed that diurnal variations of the ABL height on subsidence days and sunny days were obvious, but diurnal variations of the ABL height on rainy days were not apparent. The ABL is obviously affected by local circulation, and the ABL features are different at various stations. A simulation focused on a high pollution episode during the subsidence days on 12–15 July 2006, occurred under high-pressure conditions, accompanied by the tropical cyclone "Bilis". A comparison of the simulated vertical wind fields and temperature structure with the ABL measurements at Xinken, Panyu, and Qingyuan stations found that the modeled and measured atmospheric fields revealed two different types of ABL characteristics over the PRD. When the surface winds over the PRD were light or nearly calm, the local circulation dominated, such as the sea-land breeze at Xinken station and the mountain-valley circulation at Qingyuan station. When the surface winds were strong, the stations were under the same background weather system, and the wind directions were almost the same. Furthermore, the modeled results also suggest that the subsidence by the typhoon "Bilis" had a great impact on the high Air Pollution Index (API).

 References Chen, X. L., Feng, Y. R., Li, J. N., Lin, W. S., Fan, S. J., Wang, A. Y., Fong, S. K., and Lin, H.: Numerical simulation on the effect of sea-land breezes on atmospheric haze over the Pearl River Delta region, Environ. Model. Assess., 14, 351–363, 2009. Cheng, Y. F., Wiedensohler, A., Eichler, H., Su, H., Gnauk, T., Brüggemann, E., Herrmann, H., Heintzenberg, J., Slanina, J., Tuch, T., Hu, M., and Zhang, Y. H.: Aerosol optical properties and related chemical apportionment at Xinken in Pearl River Delta of China, Atmos. Environ., 42, 6351–6372, 2008a. Cheng, Y. F., Wiedensohler, A., Eichler, H., Heintzenberg, J., Tesche, M., Ansmann, A., Wendisch, M., Su, H., Althausen, D., Herrmann, H., Gnauk, T., Brüggemann, E., Hu, M., and Zhang, Y. H.: Relative humidity dependence of aerosol optical properties and direct radiative forcing in the surface boundary layer at Xinken in Pearl River Delta of China: an observation based numerical study, Atmos. Environ., 42, 6373–6397, 2008b. Ding, A. J., Wang, T., Zhao, M., Wang, T. J., and Li, Z. K.: Simulation of sea-land breeze and a discussion of their implication on the transport of air pollution during a multi-day ozone episode in the Pearl River Delta of China, Atmos. Environ., 38, 6737–6750, 2004. Fan, S. J., Wang, B. M., Tesche, M., Engelmann, R., Althausen, A., Liu, J., Zhu, W., Fan, Q., Li, M. H., Ta, N., Song, L. L., and Leong, K. C.: Meteorological conditions and structures of atmospheric boundary layer in October 2004 over Pearl River Delta area, Atmos. Environ., 42, 6174–6186, 2008. Feng, Y. R., Wang, A. Y., Wu, D., and Xu, X. D.: The influence of tropical cyclone Melor on PM10 concentrations during an aerosol episode over the Pearl River Delta region of China: Numerical modelling versus observational analysis, Atmos. Environ., 41, 4349–4365, 2007. Garland, R. M., Yang, H., Schmid, O., Rose, D., Nowak, A., Achtert, P., Wiedensohler, A., Takegawa, N., Kita, K., Miyazaki, Y., Kondo, Y., Hu, M., Shao, M., Zeng, L. M., Zhang, Y. H., Andreae, M. O., and Pöschl, U.: Aerosol optical properties in a rural environment near the mega-city Guangzhou, China: implications for regional air pollution, radiative forcing and remote sensing, Atmos. Chem. Phys., 8, 5161–5186, http://dx.doi.org/10.5194/acp-8-5161-2008doi:10.5194/acp-8-5161-2008, 2008. Gilliam, C. R. and Pleim, E. J.: Performance Assessment of New Land Surface and Planetary Boundary Layer Physics in the WRF-ARW, J. Appl. Meteorol. Clim., 49, 760–774, 2010. Guo, D. Z.: A study of the characteristics in the coastal boundary layer in the low latitude, Res. Environ. Sci., 5, 34–39, 1991 (in Chinese). Hanna, R. S., Reen, B., Hendrick, E., Santos, L., Stauffer, D., Deng, A. J., and McQueen, J.: Comparison of observed, MM5 and WRF-NMM model-simulated, and HPAC-assumed boundary-layer meteorological variables for 3 days during the IHOP field experiment, Bound.- Lay. Meteorol., 134, 285–306, 2010. Hu, X. M., Nielsen-Gammon, W. J., and Zhang, F. Q.: Evaluation of three planetary boundary layer schemes in the WRF model, J. Appl. Meteorol. Clim., e-View, 2010. Hua, W., Chen, Z. M., Jie, C. Y., Kondo, Y., Hofzumahaus, A., Takegawa, N., Chang, C. C., Lu, K. D., Miyazaki, Y., Kita, K., Wang, H. L., Zhang, Y. H., and Hu, M.: Atmospheric hydrogen peroxide and organic hydroperoxides during PRIDE-PRD'06, China: their concentration, formation mechanism and \mboxcontribution to secondary aerosols, Atmos. Chem. Phys., 8, 6755–6773, http://dx.doi.org/10.5194/acp-8-6755-2008doi:10.5194/acp-8-6755-2008, 2008. Huang, Z. X. and Liu, J. L.: A preliminary results of observation on sea-land breezes in Lingding Yang area, Journal of Tropical Oceanography, 3, 21–29, 1985 (in Chinese). Kwun, J. H., Kim, Y. K., Seo, J. W., Jeong, J. H., and Sung, H. Y.: Sensitivity of MM5 and WRF mesoscale model predictions of surface winds in a typhoon to planetary boundary layer parameterizations, Nat. Hazards, 51, 63–77, 2009. Jung, J. S., Lee, H. L., Kim, Y. J., Liu, X. G., Zhang, Y. H., Gu, J. W., and Fan, S. J.: Aerosol chemistry and the effect of aerosol water content on visibility impairment and radiative forcingin Guangzhou during the 2006 Pearl River Delta campaign, J. Environ. Manag., 90, 3231–3244, 2009. Jury, R. M., Chiao, S., and Harmsen, E. W.: Mesoscale Structure of Trade Wind Convection over Puerto Rico: Composite Observations and Numerical Simulation, Bound.-Lay. Meteorol., 132, 289–313, 2009. Li, X., Brauers, T., Shao, M., Garland, R. M., Wagner, T., Deutschmann, T., and Wahner, A.: MAX-DOAS measurements in southern China: retrieval of aerosol extinctions and validation using ground-based in-situ data, Atmos. Chem. Phys., 10, 2079–2089, http://dx.doi.org/10.5194/acp-10-2079-2010doi:10.5194/acp-10-2079-2010, 2010. Liang, H. M., Dong, B. Q., and Tian, G. S.: The characteristics analysis of the stratification in the ambient air over Pearl River Delta area, Res. Environ. Sci., 4, 8–14, 1992 (in Chinese). Liu, H. P. and Chan, J. C. L.: An investigation of air-pollution patterns under sea-land breezes during a server air-pollution episode in Hong Kong, Atmos. Environ., 36, 591–601, 2002. Liu, X. G., Cheng, Y. F., Zhang, Y. H., Jung, J. S., Sugimoto, N., Chang, S. Y., Kim, Y. J., Fan, S. J., and Zeng, L. M.: Influences of relative humidity and particle chemical composition on aerosol scattering properties during the 2006 PRD campaign, Atmos. Environ., 42, 1525–1536, 2008. Lou, S., Holland, F., Rohrer, F., Lu, K., Bohn, B., Brauers, T., Chang, C. C., Fuchs, H., Häseler, R., Kita, K., Kondo, Y., Li, X., Shao, M., Zeng, L., Wahner, A., Zhang, Y., Wang, W., and Hofzumahaus, A.: Atmospheric OH reactivities in the Pearl River Delta – China in summer 2006: measurement and model results, Atmos. Chem. Phys., 10, 11243–11260, http://dx.doi.org/10.5194/acp-10-11243-2010doi:10.5194/acp-10-11243-2010, 2010. Lu, K. D., Zhang, Y. H., Su, H., Shao, M., Zeng, L. M., Zhong, L. J., Xiang, Y. R., Chang, C. C., Chou, C. K. C., and Wahner, A.: Regional ozone pollution and key controlling factors of photochemical ozone production in Pearl River Delta during summer time, Science China (Chemistry), 53, 651–663, 2010. Mayer, S., Sandvik, A., Jonassen, O. M., and Reuder, J.: Atmospheric profiling with the UAS SUMO: a new perspectivefor the evaluation of fine-scale atmospheric models, Meteorol. Atmos. Phys., http://dx.doi.org/10.1007/s00703-010-0063-2doi:10.1007/s00703-010-0063-2, 2010. Miyazaki, Y., Kondo, Y., Shiraiwa, M., Takegawa, N., Miyakawa, T., Han, S., Kita, K., Hu, M., Deng, Z. Q., Zhao, Y., Sugimoto, N., Blake, D. R., and Weber, R. J.: Chemical characterization of water-soluble organic carbon aerosols at a rural site in the Pearl River Delta, China, in the summer of 2006, J. Geophys. Res.-Atmos., 114, D14208, http://dx.doi.org/10.1029/2009JD011736doi:10.1029/2009JD011736, 2009. Miao, S. G., Chen, F., Margaret, A., LeMone, Tewari, M., Li, Q. C., and Wang, Y. C.: An Ob- servational and Modeling Study of Characteristics of Urban Heat Island and Boundary Layer Structures in Beijing, J. Appl. Meteorol. Clim., 48, 484–501, 2009. Nolan, S. D., Zhang, A. J., and Stern, P. D.: Evaluation of planetary boundary layer param- eterizations in tropical cyclones by comparison of in situ observations and high-resolution simulations of hurricane Isabel (2003) – Part I: Initialization, maximum winds, and the outer- core boundary layer, Mon. Weather Rev., 137, 3651–3674, 2009a. Nolan, S. D., Zhang, A. J., and Stern, P. D.: Evaluation of planetary boundary layer parameterizations in tropical cyclones by comparison of in situ observations and high-resolution simulations of hurricane Isabel (2003) – Part II: Inner-core boundary layer and eyewall structure, Mon. Weather Rev., 137, 3675–3698, 2009b. Prtenjak, M. T., Jeričevi\'c, A., Kraljevi\'c, L., Buli\'c, I. H., Nitis, T., and Klai\'c, Z. B.: Exploring atmospheric boundary layer characteristics in a severe SO2 episode in the north-eastern Adriatic, Atmos. Chem. Phys., 9, 4467–4483, http://dx.doi.org/10.5194/acp-9-4467-2009doi:10.5194/acp-9-4467-2009, 2009. Rose, D., Nowak, A., Achtert, P., Wiedensohler, A., Hu, M., Shao, M., Zhang, Y., Andreae, M. O., and Pöschl, U.: Cloud condensation nuclei in polluted air and biomass burning smoke near the mega-city Guangzhou, China – Part 1: Size-resolved measurements and implications for the modelling of aerosol particle hygroscopicity and CCN activity, Atmos. Chem. Phys., 10, 3365–3383, http://dx.doi.org/10.5194/acp-10-3365-2010doi:10.5194/acp-10-3365-2010, 2010. Skamarock, W. C., Klemp, J. B., Dudhia, J., Gill, D. O., Barker, D. M., Wang, W., and Powers, J. G.: A description of the Advanced Research WRF Version 2, NCAR/TN-468+STR, Ncar Technical Note, 88 pp., available at: http://www.mmm.ucar.edu/wrf/users/docs/arw_v2. pdf, January 2007. %Verma, R. L., Sahu, L. K., Kondo, Y., Takegawa, N., Han, S., Jung, J. S., %Kim, Y. J., Fan, S., Sugimoto, N., Shammaa, M. H., Zhang, Y. H., and Zhao, %Y.: Temporal variation of elemental carbon in Guangzhou, China, in summer %2006, Atmos. Chem. Phys. Discuss., 9, 24629–24667, http://dx.doi.org/10.5194/acpd-9-24629-2009doi:10.5194/acpd-9-24629-2009, 2009. Verma, R. L., Sahu, L. K., Kondo, Y., Takegawa, N., Han, S., Jung, J. S., Kim, Y. J., Fan, S., Sugimoto, N., Shammaa, M. H., Zhang, Y. H., and Zhao, Y.: Temporal variations of black carbon in Guangzhou, China, in summer 2006, Atmos. Chem. Phys., 10, 6471–6485, http://dx.doi.org/10.5194/acp-10-6471-2010doi:10.5194/acp-10-6471-2010, 2010. Wang, X. M., Lin, W. S., Yang, L. M., Deng, R. R., and Lin, H., A numerical study of influences of urban land-use change on ozone distribution over the Pearl River Delta region, China. Tellus B, 59B, 633–641, 2007. Wu, D., Tie, X. X., Li, C. C., Ying, Z. M., Lau, A. K. H., Huang, J., Deng, X. J., and Bi, X. Y.: An extremely low visibility event over the Guangzhou region: a case study, Atmos. Environ., 39, 6568–6577, 2005. Xiao, R., Takegawa, N., Kondo, Y., Miyazaki, Y., Miyakawa, T., Hu, M., Shao, M., Zeng, L. M.,Hofzumahaus, A., Holland, F., Lu, K., Sugimoto, N., Zhao, Y., and Zhang, Y. H.: Formation of submicron sulfate and organic aerosols in the outflow from the urban region of the Pearl River Delta in China, Atmos. Environ., 43, 3754–3763, 2009. Yu, H., Wu, C., Wu, D., and Yu, J. Z.: Size distributions of elemental carbon and its contribution to light extinction in urban and rural locations in the Pearl River delta region, China, Atmos. Chem. Phys., 10, 5107–5119, http://dx.doi.org/10.5194/acp-10-5107-2010doi:10.5194/acp-10-5107-2010, 2010. Yu, S., Eder, B., Dennis, R., Chu, S. H., and Schwariz, S.: On the development of new metrics for the evaluation of air quality models, Atmos. Sci. Lett., 7, 26–34, 2005. Zhang, Y. H., Su, H., Zhong, L. J., Cheng, Y. F., Zeng, L. M., Wang, X. S., Xiang, Y. R., Wang, J. L., Gao, D. F., Shao, M., Fan, S. J., and Liu, S. C.: Regional ozone pollution and observation-based approach for analyzing ozone–precursor relationship during the PRIDE- PRD2004 campaign, Atmos. Environ., 42, 6203–6218, 2008a. Zhang, Y. H., Hu, M., Zhong, L. J., Wiedensohlerg, A., Liu, S. C., Andreae, M. O., Wang, W., and Fan S. J.: Regional integrated experiments on air quality over Pearl River Delta 2004(PRIDE-PRD2004): overview, Atmos. Environ., 42, 6157–6173, 2008b. Zhu, P.: A multiple scale modelling system for coastal hurricane wind damage mitigation, Nat. Hazards, 47, 577–591, 2008.