Atmospheric Chemistry and Physics Discussions
www.atmos-chem-phys-discuss.net
1680-7367
1680-7375
6
6
2006
10.5194/acpd-6-13323-2006
http://www.atmos-chem-phys-discuss.net/6/13323/2006/
http://www.atmos-chem-phys-discuss.net/6/13323/2006/acpd-6-13323-2006.html
http://www.atmos-chem-phys-discuss.net/6/13323/2006/acpd-6-13323-2006.pdf
13323
13366
2006-12-19
Regional pollution potentials of megacities and other major population centers
M. G. Lawrence
lawrence@mpch-mainz.mpg.de
T. M. Butler
J. Steinkamp
B. R. Gurjar
J. Lelieveld
Max-Planck-Institut für Chemie, Postfach 3060, 55020 Mainz, Germany
Indian Institute of Technology (IIT) – Roorkee, Department of Civil Engineering, Roorkee 247667, India
Megacities and other major population centers represent important,
concentrated sources of anthropogenic pollutants to the atmosphere, with
consequences for both local air quality and for regional and global
atmospheric chemistry. The tradeoff between the regional buildup of
pollutants near their sources versus long-range export depends on
meteorological characteristics which vary as a function of geographical
location and season. Both horizontal and vertical transport contribute to
pollutant export, and the overall degree of export is strongly governed by the
chemical lifetimes of pollutants. We provide a first quantification of this
tradeoff and the main factors influencing it in terms of "regional pollution
potentials", metrics based on simulations of artificial, representative
tracers using the 3-D global model MATCH (Model of Atmospheric Transport and
Chemistry). The tracers have three different lifetimes (1, 10, and 100 days)
and are emitted from 36 continental point sources representing the 30 current
largest cities around the world plus 6 additional major population centers.
Several key features of the export characteristics emerge: 1) long-range
near-surface pollutant export is generally strongest in the middle and high
latitudes, especially for source locations in Eurasia; 2) on the other hand,
pollutant export to the upper troposphere is greatest in the tropics, due to
transport by deep convection; 3) not only are there order of magnitude
interregional differences, such as between low and high latitudes, but also
often substantial intraregional differences, for instance between the sources
in western India and Pakistan versus eastern India and Bangladesh; 4) contrary
to what one might initially expect, efficient long-range export does not
necessarily correspond with a more significant dilution of pollutants near
their source, rather the amount of low-level, long-range export (e.g., below
1 km and beyond 1000 km) is well-correlated with exceedences of surface
density thresholds on regional scales near the source (e.g., within ~1000 km), implying that pollutant buildup to high densities in the surface
layer of the region surrounding the source location is more strongly
influenced by vertical than horizontal transport.
%
Chameides, W L., Kasibhatla, P S., Yienger, J., and II, H L.: Growth of continental-scale metro-agro-plexes, regional ozone pollution, and world food production, Science, 264, 74–77, 1994.
Crutzen, P J. and Lawrence, M G.: The Impact of Precipitation Scavenging on the Transport of Trace Gases: A 3-dimensional Model Sensitivity Study, J. Atmos. Chem., 37, 81–112, 2000.
de~Foy, B., Varela, J R., Molina, L T., and Molina, M J.: Rapid ventilation of the Mexico City basin and regional fate of the urban plume, Atmos. Chem. Phys., 6, 2321–2335, 2006.
Emberson, L., Ashmore, M., Murray, F., Kuylenstierna, J., Percy, K., Izuta, T., Zheng, Y., Shimizu, H., Sheu, B., Liu, C., Agrawal, M., Wahid, A., Abdel-Latif, N., van Tienhoven, M., de~Bauer, L., and Domingos, M.: Impacts of air pollutants on vegetation in developing countries, Water, Air Soil Pollut., 130, 107–118, 2001.
Ganguly, D., Jayaraman, A., Rajesh, T A., and Gadhavi, H.: Wintertime aerosol properties during foggy and nonfoggy days over urban center Delhi and their implications for shortwave radiative forcing, J. Geophys. Res., 111, D15217, doi:10.1029/2005JD007029, 2006.
Gros, V., Williams, J., van Aardenne, J A., Salisbury, G., Hofmann, R., Lawrence, M G., von Kuhlmann, R., Lelieveld, J., Krol, M., Berresheim, H., Lobert, J M., and Atlas, E.: Origin of anthropogenic hydrocarbons and halocarbons measured in the summertime European outflow (on Crete in 2001), Atmos. Chem. Phys., 3, 1223–1235, 2003.
Gros, V., Williams, J., Lawrence, M G., von Kuhlmann, R., van Aardenne, J A., Atlas, E., Chuck, A., Edwards, D P., Stroud, V., , and Krol, M.: Tracing the origin and ages of interlaced atmospheric pollution events over the tropical Atlantic Ocean with in-situ measurements, satellites, trajectories, emission inventories and global models, J. Geophys. Res., 109, D22306, doi:10.1029/2004JD004846, 2004.
Gurjar, B. and Lelieveld, J.: New Directions: Megacities and global change, Atmos. Environ., 39, 391–393, 2005.
Gurjar, B., van Aardenne, J., Lelieveld, J., and Mohan, M.: Emission estimates and trends (1990–2000) for megacity Delhi and implications, Atmos. Environ., 38, 5663–5681, 2004.
Guttikunda, S., Tang, Y., Carmichael, G., Kurata, G., Pan, L., Streets, D., Woo, J.-H., Thongboonchoo, N., and Fried, A.: Impacts of Asian megacity emissions on regional air quality during spring 2001, J. Geophys. Res., 110, D20301, doi:10.1029/2004JD004921, 2005.
Heald, C., Jacob, D., Palmer, P., Evans, M., Sachse, G., Singh, H., and Blake, D.: Biomass burning emission inventory with daily resolution: Application to aircraft observations of Asian outflow, J. Geophys. Res., 108, 8811, doi:10.1029/2002JD003082, 2003.
Kalnay, E., Kanamitsu, M., Kistler, R., Collins, W., Deaven, D., Gandin, L., Iredell, M., Saha, S., White, G., Woollen, J., Zhu, Y., Chelliah, M., Ebisuzaki, W., Higgins, W., Janowiak, J., Mo, K C., Ropelewski, C., Wang, J., Leetmaa, A., Reynolds, R., Jenne, R., and Joseph, D.: The NCEP/NCAR 40-year reanalysis project, Bull. Am. Meteorol. Soc., 77, 437–471, 1996.
Kiehl, J T., Bonan, G B., Boville, B A., Briegleb, B P., Williamson, D L., and Rasch, P J.: Description of the NCAR Community Climate Model (CCM3), NCAR Tech. Note NCAR /TN-420+STAR, Nat. Cent. Atmos. Res., Boulder, CO, 1996.
Kunhikrishnan, T. and Lawrence, M G.: Sensitivity of NO<sub>2</sub> over the Indian Ocean to emissions from the surrounding continents and nonlinearities in atmospheric chemistry responses, Geophys. Res. Lett., 31, L15109, doi:10.1029/2003GL020210, 2004.
Lacis, A A., Wuebbles, D J., and Logan, J A.: Radiative forcing of climate by changes in the vertical distribution of ozone, J. Geophys. Res., 95, 9971–9981, 1990.
Lang, R. and Lawrence, M G.: Evaluation of the hydrological cycle of MATCH driven by NCEP reanalysis data: comparison with GOME water vapor field measurements, Atmos. Chem. Phys., 5, 887–908, 2005a.
Lang, R. and Lawrence, M G.: Improvement of the vertical humidity distribution in the chemistry-transport model MATCH through increased evaporation of convective precipitation, Geophys. Res. Lett., 32, L17812, doi:10.1029/2005GL023172, 2005b.
Lawrence, M G. and Rasch, P J.: Tracer transport in deep convective updrafts: plume ensemble versus bulk formulations, J. Atmos. Sci., 62, 2880–2894, 2005.
Lawrence, M G., Crutzen, P J., Rasch, P J., Eaton, B E., and Mahowald, N M.: A model for studies of tropospheric photochemistry: Description, global distributions, and evaluation, J. Geophys. Res., 104, 26 245–26 277, 1999.
Lawrence, M G., Rasch, P J., von Kuhlmann, R., Williams, J., Fischer, H., de Reus, M., Lelieveld, J., Crutzen, P J., Schultz, M., Stier, P., Huntrieser, H., Heland, J., Stohl, A., Forster, C., Elbern, H., Jakobs, H., and Dickerson, R R.: Global chemical weather forecasts for field campaign planning: predictions and observations of large-scale features during MINOS, CONTRACE, and INDOEX, Atmos. Chem. Phys., 3, 267–289, 2003a.
Lawrence, M G., von Kuhlmann, R., Salzmann, M., and Rasch, P J.: The balance of effects of deep convective mixing on tropospheric ozone, Geophys. Res. Lett., 30, 1940, doi:10.1029/2003GL017644, 2003b.
Lelieveld, J., Crutzen, P J., Ramanathan, V., Andreae, M O., Brenninkmeijer, C. A M., Campos, T., Cass, G R., Dickerson, R R., Fischer, H., de~Gouw, J A., Hansel, A., Jefferson, A., Kley, D., de~Laat, A. T J., Lal, S., Lawrence, M G., Lobert, J M., Mayol-Bracero, O L., Mitra, A P., Novakov, T., Oltmans, S J., Prather, K A., Reiner, T., Rodhe, H., Scheeren, H A., Sikka, D., and Williams, J.: The Indian Ocean Experiment: Widespread Air Pollution from South and Southeast Asia, Science, 291, 1031–1036, 2001.
Lohmann, U.: A glaciation indirect aerosol effect caused by soot aerosols, Geophys. Res. Lett., 29, 1052, doi:10.1029/2001GL014357, 2002.
Mahowald, N M., Prinn, R., and Rasch, P J.: Deducing CCl<sub>3</sub>F emissions using an inverse method and chemical transport models with assimilated winds, J. Geophys. Res., 102, 28 153–28 168, 1997a.
Mahowald, N M., Rasch, P J., Eaton, B E., Whittlestone, S., and Prinn, R G.: Transport of $^222$radon to the remote troposphere using the Model of Atmospheric Transport and Chemistry and assimilated winds from ECMWF and the National Center for Environmental Prediction/NCAR, J. Geophys. Res., 102, 28 139–28 152, 1997b.
Marufu, L T., Taubman, B F., Bloomer, B., Piety, C A., Doddridge, B G., Stehr, J W., and Dickerson, R R.: The 2003 North American electrical blackout: An accidental experiment in atmospheric chemistry, Geophys. Res. Lett., 31, L13106, doi:10.1029/2004GL019771, 2004.
Molina, M J. and Molina, L T.: Megacities and atmospheric pollution, J. Air Waste Manage. Assoc., 54, 644–680, 2004.
National Imagery and Mapping Agency, http://earth-info.nga.mil/GandG/publications/tr8350.2/wgs84fin.pdf, Tech. rep, 2000.
Pfister, G., Petron, G., Emmons, L., Gille, J., Edwards, D., Lamarque, J., Attie, J., Granier, C., and Novelli, P.: Evaluation of CO simulations and the analysis of the CO budget for Europe, J. Geophys. Res., 109, D19304, doi:10.1029/2004JD004691, 2004.
Prather, M J.: Time scales in atmospheric chemistry: Theory, GWPs for CH<sub>4</sub> and CO, and runaway growth, Geophys. Res. Lett., 23, 2597–2600, 1996.
Ramanathan, V., Crutzen, P J., Mitra, A P., and Sikka, D.: The Indian Ocean Experiment and the Asian Brown Cloud, Curr. Sci., 83, 947–955, 2002.
Rasch, P J., Mahowald, N M., and Eaton, B E.: Representations of transport, convection and the hydrologic cycle in chemical transport models: Implications for the modeling of short lived and soluble species, J. Geophys. Res., 102, 28 127–28 138, 1997.
Salisbury, G., Williams, J., Holzinger, R., Gros, V., Mihalopoulos, N., Vrekoussis, M., Sarda-Estève, R., Berresheim, H., von Kuhlmann, R., Lawrence, M., and Lelieveld, J.: Ground-based PTR-MS measurements of reactive organic compounds during the MINOS campaign in Crete, July–August 2001, Atmos. Chem. Phys., 3, 925–940, 2003.
Stohl, A.: A 1-year lagrangian "climatology" of airsteams in the Northern Hemisphere troposphere and lowermost stratosphere, J. Geophys. Res., 106, 7263–7279, 2001.
Stohl, A., Eckhardt, S., Forster, C., James, P., and Spichtinger, N.: On the pathways and timescales of intercontinental air pollution transport, J. Geophys. Res., 107, 4684, doi:10.1029/2001JD001396, 2002.
von Kuhlmann, R., Lawrence, M G., Crutzen, P J., and Rasch, P J.: A model for studies of tropospheric ozone and non-methane hydrocarbons: Model description and ozone results, J. Geophys. Res., 108, 4294, doi:10.1029/2002JD002893, 2003.
WMO: Scientific Assessment of Ozone Depletion: 2002, Global ozone research and monitoring project – report no. 47, 498 pp., WMO, Geneva, 2002.