References

ACPD

Atmospheric Chemistry and Physics Discussions

ACPD

1680-7375

Copernicus GmbH

Göttingen, Germany

10.5194/acpd-8-15855-2008

Effects of sea surface winds on marine aerosols characteristics and impacts on longwave radiative forcing over the Arabian Sea

Nair

Vijayakumar S.

¹ Suresh Babu

¹ Satheesh

S. K.

² Krishna Moorthy

Space Physics Laboratory, Vikram Sarabhai Space Centre, Trivandrum, 695 022, India

Centre for Atmospheric and Oceanic Science, Indian Institute of Sciences, Bangalore, India

20 08 2008

8 4 15855 15899

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Collocated measurements of spectral aerosol optical depths (AODs), total and BC mass concentrations, and number size distributions of near surface aerosols, along with sea surface winds, made onboard a scientific cruise over southeastern Arabian Sea, are used to delineate the effects of changes in the wind speed on aerosol properties and its implication on the shortwave and longwave radiative forcing. The results indicated that an increase in the sea-surface wind speed from calm to moderate (<1 to 8 m s<sup>−1</sup>) values results in a selective increase of the particle concentrations in the size range 0.5 to 5 μm, leading to significant changes in the size distribution, increase in the mass concentration, decrease in the BC mass fraction, a remarkable increase in AODs in the near infrared and a flattening of the AOD spectrum. The consequent increase in the longwave direct radiative forcing almost entirely offsets the corresponding increase in the short wave direct radiative forcing (or even overcompensates) at the top of the atmosphere; while the surface forcing is offset by about 50%.

References 1

Arnott, W. P., Hamasha, K., Moosmuller, H., Sheridan, P. J., and Ohren, J. A.: Towards aerosol light-absorption measurements with a 7-wavelength aethalometer: evaluation with a photoacoustic instrument and 3-wavelength nephelometer, Aerosol Sci. Technol., 39(1), 17–29, 2005.

Babu, S. S., Moorthy, K. K., and Satheesh, S. K.: Aerosol black carbon over Arabian Sea during intermonsoon season and summer monsoon season, Geophys. Res. Lett., 31, L06104, doi:10.1029/2003GL018716, 2004.

Bates, T. S., Anderson, T. L., Baynard, T.,, et al.: Aerosol direct radiative effects over the northwest Atlantic, northwest Pacific, and North Indian Oceans: estimates based on in-situ chemical and optical measurements and chemical transport modeling, Atmos. Chem. Phys., 6, 1657–1732, 2006.

Bates, T. S., Quinn, P. K., Coffman, D. J., Covert, D. S., Miller, T. L., Johnson, J. E., Carmichael, G. R., Guazzotti, S. A., Sodeman, D. A., Prather, K. A., Rivera, M., Russell, L. M., and Merrill, J. T.: Marine boundary layer dust and pollution transport associated with the passage of a frontal system over eastern Asia, J. Geophys. Res., 109, D19, doi:10.1029/2003JD004094, 2004.

Chin, M., Ginoux, P., Kinne, S., Holben, B. N., Duncan, B. N., Martin, R. V., Logan, J. A., Higurashi, A., and Nakajima, T.: Tropospheric aerosol optical thickness from the GOCART model and comparisons with satellite and sunphotometer measurements, J. Atmos. Sci. 59, 461–483, 2002.

Corrigan, C. E., Ramanathan, V., and Schauer, J. J.: Impact of monsoon transitions on the physical and optical properties of aerosols, J. Geophys. Res., 111, D18208, doi:10.1029/2005JD006370, 2006.

Draxler, R. R. and Rolph, G. D.: HYSPLIT (Hybrid Single Particle Lagrangian Integrated Trajectory) model access, available at: http://www.arl.noaa.gov/ready/hysplit4.html, 2003.

Dupont, J.-C., Haeffelin, M., Drobinski, P., and Besnard, T.: Parametric model to estimate clear-sky longwave irradiance at the surface on the basis of vertical distribution of humidity and temperature, J. Geophys. Res., 113, D07203, doi:10.1029/2007JD009046, 2008.

Exton, H. J., Latham, J., Park, P. M., Perry, S. J., and Smith, M. H.: The production and dispersal of marine aerosol, Q. J. Roy. Meteorol. Soc., 111, 817–837, 1985.

Fitzgerald, J. W.: Marine Aerosols: a review, Atmos. Environ., 25A, 533–545, 1991.

Ganguly, D., Jayaraman, A., and Gadhavi, H.: In situ ship cruise measurements of mass concentration and size distribution of aerosols over Bay of Bengal and their radiative impacts, J. Geophys. Res., 110, D06205, doi:10.1029/2004JD005325, 2005.

Gong, S. L.: Parameterization of sea salt aerosol source function for sub and super micron particles, Global Biogeochem. Cy., 17, 4, 1097, doi:10.1029/2003GB002079, 2003.

Gras, J. L. and Ayers, G. P.: Marine aerosol at southern mid-latitudes, J. Geophys. Res., 88, 10 661–10 666, 1983.

Hess, M., Koepke, P., and Schult, I.: Optical properties of aerosols and clouds: The software package (OPAC), B. Am. Meteorol. Soc., 79, 831–844, 1998.

Hitzenberger, R., Petzold, A., Bauer, H., Ctyroky, P., Pouresmaeil, P., Laskus, L., and Puxbaum, H.: Intercomparison of thermal and optical measurement methods for elemental carbon and black carbon at an urban location, Environ. Sci. Technol., 15, 40(20), 6377–6383, 2006.

Hollweg, H.-D., Bakan, S., and Taylor, J. P.: Is the aerosol emission detectable in the thermal infrared?, J. Geophys. Res., 111, D15202, doi:10.1029/2005JD006432, 2006.

Huang, Y., Ramaswamy, V., and Soden, B.: An investigation of the sensitivity of the clear-sky outgoing longwave radiation to atmospheric temperature and water vapor, J. Geophys. Res., 112, D05104, doi:10.1029/2005JD006906, 2007.

Johansen, A. M. and Hoffmann, M. R.: Chemical characterization of ambient aerosol collected during the northeast monsoon season over the Arabian Sea: Labile-Fe(II) and other trace metals, J. Geophys. Res., 108(D14), 4408, doi:10.1029/2002JD003280, 2003.

Latham, J. and Smith, M. H.: Effect on global warming of wind-dependent aerosol generation at the ocean surface, Nature, 347, 372–373, 1990.

Lovett, R. F.: Quantitative measurement of airborne sea-salt in the Northern Atlantic, Tellus, 30, 358–364, 1978.

Lubin, D., Satheesh, S. K., McFarquar, G., and Heymsfield, A. J.: Longwave radiative forcing of Indian Ocean tropospheric aerosol, J. Geophys. Res., 107(D19), 8004, doi:10.1029/2001JD001183, 2002.

Markowicz, K. M., Flatau, P. J., Vogelmann, A. M., Quinn, P. K., and Welton, E. J.: Clear sky infrared aerosol radiative forcing at the surface and the top of the atmosphere, Q. J. Roy. Meteorol. Soc., 129, 2927–2947, 2003.

Moorthy, K. K., Satheesh, S. K., and Murthy, B. V. K.: Investigations of Marine Aerosols over the Tropical Indian Ocean, J. Geophys. Res., 102, 18 827–18 842, 1997.

Moorthy, K. K., Babu, S. S., and Satheesh, S. K.: Aerosol Characteristics and Radiative Impacts over the Arabian Sea during the Intermonsoon Season: Results from ARMEX Field Campaign, J. Atmos. Sci., 62(1), 192–206, 2005a.

Moorthy, K. K., Satheesh, S. K., Babu, S. S., and Saha, A.: Large latitudinal gradients and temporal heterogeneity in aerosol black carbon and its mass mixing ratio over southern and northern oceans during a trans-continental cruise experiment, Geophys. Res. Lett., 32, L14818, doi:10.1029/2005GL023267, 2005b.

Nilsson, E. D., Rannik, U., Swietlicki, E., Leek, C., Aalto, P. P., Zhou, J., and Norman, M.: Turbulent aerosol fluxes over the Arctic Ocean 2. Wind-driven sources from the sea, J. Geophys. Res., 106(D23), 32 139–32 154, 2001.

O'Dowd, C. D. and Smith, M. H.: Physicochemical properties of aerosols over the Northeast Atlantic: Evidence for wind-speed-related submicron sea-salt aerosol production, J. Geophys. Res., 98(D1), 1137–1149, 1993.

O'Dowd, C. D., Smith, M. H., Consterdine, I. E., and Lowe, J. A.: Marine aerosol, sea-salt and the marine sulphur cycle: a short review, Atmos. Environ., 31, 73–80, 1997.

Panicker, A. S., Pandithurai, G., Safai, P. D., and Kewat, S.: Observations of enhanced aerosol longwave radiative forcing over an urban environment, Geophys. Res. Lett., 35, L04817, doi:10.1029/2007GL032879, 2008.

Podgorny, I. A., Conant, W. C., Ramanathan, V., and Satheesh, S. K.: Aerosol modulation of atmospheric and surface solar heating rates over the tropical Indian Ocean, Tellus B, 53, 947–958, 2000.

Porter, J. N., Miller, M., Pietras, C., and Motell, C.: Ship based sun photometer measurements using Microtops sun photometer, J. Atmos. Oceanic Technol., 18, 765–744, 2001.

Ramachandran, S. and Jayaraman, A.: Premonsoon aerosol loading and size distribution over the Arabian Sea and the Tropical Indian Ocean, J. Geophys. Res., 107, 4738, doi:10.1029/2002JD002386, 2002.

Ramanathan, V., Crutzen, P. J., Lelieveld, J., Mitra, A. P., Althausen, D., et al.: Indian Ocean experiment: an integrated analysis of the climate forcing and effects of the great Indo-Asian haze, J. Geophys. Res., 106(D22), 28 371–28 398, doi:10.1029/2001JD900133, 2001.

Ricchiazzi, P., Yang, S., Gautier, C., and Sowle, D.: SBDART: a Research and Teaching Software Tool for Plane-Parallel Radiative Transfer in the Earth's Atmosphere, B. Am. Meteorol. Soc., 79, 2101–2114, 1998.

Satheesh, S. K. and Lubin, D.: Short wave versus long wave radiative forcing by Indian Ocean aerosols: role of sea-surface winds, Geophys. Res. Lett., 30, 13, doi:10.1029/2003GL017499, 2003.

Satheesh, S. K. and Srinivasan, J.: Enhanced aerosol loading over Arabian Sea during the pre-monsoon season: Natural or anthropogenic?, Geophys. Res. Lett., 29, 18, doi:10.1029/2002GL015687, 2002.

Satheesh, S. K., Moorthy, K. K., Kaufman, Y. J., and Takemura, T.: Aerosol optical depth, physical properties and radiative forcing over the Arabian Sea, Meteorol. Atmos. Phys., 91, 45–62, 2006.

Satheesh, S. K., Ramanathan, V., Jones, X. L., Lobert, J. M., Podgorny, I. A., Prospero, J. M., Holben, B. N., and Loeb, N. G.: A Model for Natural and Anthropogenic Aerosols over the Tropical Indian Ocean Derived from INDOEX data, J. Geophys. Res., 104(D22), 27 421–27 440, 1999.

Satheesh, S. K.: Aerosol radiative forcing over tropical Indian Ocean: Modulation by sea surface winds, Curr. Sci., 82, 310–316, 2002.

Shenoy, D. M., Joseph, S., Dileep Kumar, M., and George, M. D.: Control and inter-annual variability of dimethyl sulfide in the Indian Ocean, J. Geophys. Res., 107(D19), 8008, doi:10.1029/2001JD00371, 2002.

Smirnov, A., Holben, B. N., Eck, T. F., Dubovik, O., and Slusker, I.: Effect of wind speed on columnar aerosol optical properties at Midway Island, J. Geophys. Res., 108(D24), 4802, doi:10.1029/2003JD003879, 2003.

Smirnov, A., Holben, B. N., Kaufman, Y. J., Dubovik, O., Eck, T. F., Slutsker, I., Pietras, C., and Halthore, R. N.: Optical properties of atmospheric aerosol in maritime environments, J. Atmos. Sci., 59, 501–523, 2002.

Smith, M. H., Consterdine, I. E., and Park, P. M.: Atmospheric loadings of marine aerosol during Hebridean cyclone, Q. J. Roy. Meteorol. Soc., 115, 383–395,1989.

Tsunogai, S., Saito, O., Yamada, K., and Nakaya, S.: Chemical composition of oceanic aerosol, J. Geophys. Res., 77, 5283–5291, 1972.

Vogelmann, A. M., Flatau, P. J., Szczodrak, M., Markowicz, K. M., and Minnett, P. J.: Observations of large aerosol infrared forcing at the surface, Geophys. Res. Lett., 30(12), 1655, doi:10.1029/2002GL016829, 2003.

Weingartner, E., Saathoff, H., Schnaiter, M., Streit, N., Bitnar, B., and Baltensperger, U.: Absorption of light by soot particles: determination of the absorption coefficient by means of aethalometers, J. Aerosol Sci., 34, 1445–1463, 2003.

Zhu, A., Ramanathan, V., Li, F., and Kim, D.: Dust plumes over the Pacific, Indian, and Atlantic oceans: Climatology and radiative impact, J. Geophys. Res., 112, D16208, doi:10.1029/2007JD008427, 2007.