Extremely high aerosol loading over Arabian Sea during June 2008: The specific role of the atmospheric dynamics and Sistan dust storms

This study focuses on analyzing the extreme aerosol loading and the mechanisms, source areas and meteorological conditions that favored the abnormal dust exposure towards Arabian Sea during June 2008. The analysis reveals that the spatial-averaged aerosol optical depth (AOD) over Arabian Sea in June 2008 is 0.5 (78.2%) higher than the 2000–2013 mean June value and is mostly attributed to the enhanced dust activity and several (18) dust storms originated from the Sistan region (Iran–Afghanistan borders). Landsat images show that the marshy lakes in Sistan basin got dried during the second half of June 2008 and the alluvial silt and saline material got easily eroded by the intense Levar winds, which were stronger (>15–20 m s−1) than the climatological mean for the month of June. These conditions led to enhanced dust exposure from Sistan that strongly affected the northern and central parts of the Arabian Sea, as forward air-mass trajectories show. The NCEP/NCAR reanalysis reveals an abnormal intensification and spatial expansion of the Indian low pressure system towards northern Arabian Sea in June 2008. This suggests strengthening of the convection over the arid southwest Asia and exposure of significant amount of dust, which can reach further south over Arabian Sea favored by the enhanced cyclonic circulation. MODIS imagery highlighted several dust storms originated from Sistan and affecting Arabian Sea during June 2008, while the SPRINTARS model simulations of increased AOD and dust concentration over Sistan and downwind areas are in agreement with ground-based and satellite observations.

[1]  T. Eck,et al.  Global evaluation of the Collection 5 MODIS dark-target aerosol products over land , 2010 .

[2]  Mannava V. K. Sivakumar,et al.  Climate and Land Degradation , 2007 .

[3]  Panagiotis T. Nastos,et al.  Characterising the long‐range transport mechanisms of different aerosol types over Athens, Greece during 2000–2005 , 2012 .

[4]  V. Vinoj,et al.  Assessment of Aerosol Radiative Impact over Oceanic Regions Adjacent to Indian Subcontinent Using Multisatellite Analysis , 2010 .

[5]  B. Abish,et al.  Absorbing aerosol variability over the Indian subcontinent and its increasing dependence on ENSO , 2013 .

[6]  T. N. Krishnamurti,et al.  Aerosol and pollutant transport and their impact on radiative forcing over the tropical Indian Ocean during the January February 1996 pre-INDOEX cruise , 1998 .

[7]  M. G. Manoj,et al.  Lidar investigation of aerosol–cloud–precipitation interactions over a tropical monsoon environment: Recharging of atmosphere , 2013 .

[8]  Ming Zhao,et al.  Global‐scale attribution of anthropogenic and natural dust sources and their emission rates based on MODIS Deep Blue aerosol products , 2012 .

[9]  D. Kaskaoutis,et al.  Assessment of chemical and mineralogical characteristics of airborne dust in the Sistan region, Iran. , 2013, Chemosphere.

[10]  A. Goudie,et al.  Desert dust and human health disorders. , 2014, Environment international.

[11]  Y. Tsushima,et al.  Modeling of the radiative process in an atmospheric general circulation model. , 2000, Applied optics.

[12]  C. Flamant,et al.  Spatio-temporal variability of dust aerosols over the Sistan region in Iran based on satellite observations , 2014, Natural Hazards.

[13]  Larry Di Girolamo,et al.  A climatology of aerosol optical and microphysical properties over the Indian subcontinent from 9 years (2000–2008) of Multiangle Imaging Spectroradiometer (MISR) data , 2010 .

[14]  Panagiotis T. Nastos,et al.  Meteorological Patterns Associated with Intense Saharan Dust Outbreaks over Greece in Winter , 2012 .

[15]  P. Devara,et al.  Aerosol optical depth variability over Arabian Sea during drought and normal years of Indian monsoon , 2008 .

[16]  Dale A. Gillette,et al.  A wind tunnel simulation of the erosion of soil: Effect of soil texture, sandblasting, wind speed, and soil consolidation on dust production , 1978 .

[17]  M. Ekhtesasi,et al.  Determining Area Affected by Dust Storms in Different Wind Speeds, Using Satellite Images , 2012 .

[18]  Yaping Shao,et al.  Climatology of the Middle East dust events , 2013 .

[19]  R. Kahn,et al.  Dryness of ephemeral lakes and consequences for dust activity: the case of the Hamoun drainage basin, southeastern Iran. , 2013, The Science of the total environment.

[20]  T. Takemura,et al.  A study of uncertainties in the sulfate distribution and its radiative forcing associated with sulfur chemistry in a global aerosol model , 2011 .

[21]  Dimitris G. Kaskaoutis,et al.  Dust storms and their horizontal dust loading in the Sistan region, Iran , 2012 .

[22]  K.,et al.  Aerosol Characteristics and Radiative Impacts over the Arabian Sea during the Intermonsoon Season: Results from ARMEX Field Campaign , 2005 .

[23]  B. Lyon,et al.  Drought in Central and Southwest Asia: La Niña, the Warm Pool, and Indian Ocean Precipitation. , 2002 .

[24]  S. S. Prijith,et al.  Multi-year observations of the spatial and vertical distribution of aerosols and the genesis of abnormal variations in aerosol loading over the Arabian Sea during Asian summer monsoon season , 2013 .

[25]  D. E. Spiel,et al.  A Model of Marine Aerosol Generation Via Whitecaps and Wave Disruption , 1986 .

[26]  Saeed Golian,et al.  Comparison of dust source identification techniques over land in the Middle East region using MODIS data , 2012 .

[27]  Thomas Blaschke,et al.  Aerosol Optical Properties and radiative forcing over mega-city Karachi , 2011 .

[28]  Nick Middleton,et al.  Dust storms in the Middle East , 1986 .

[29]  O. Torres,et al.  ENVIRONMENTAL CHARACTERIZATION OF GLOBAL SOURCES OF ATMOSPHERIC SOIL DUST IDENTIFIED WITH THE NIMBUS 7 TOTAL OZONE MAPPING SPECTROMETER (TOMS) ABSORBING AEROSOL PRODUCT , 2002 .

[30]  Pcs Devara,et al.  Identification of aerosol type over the Arabian Sea in the premonsoon season during the Integrated Campaign for Aerosols, Gases and Radiation Budget (ICARB) , 2009 .

[31]  P. Pease,et al.  Aerosols over the Arabian Sea: Atmospheric transport pathways and concentrations of dust and sea salt , 1999 .

[32]  W. Collins,et al.  An AeroCom Initial Assessment - Optical Properties in Aerosol Component Modules of Global Models , 2005 .

[33]  Zhaoyan Liu,et al.  Two contrasting dust‐dominant periods over India observed from MODIS and CALIPSO data , 2009 .

[34]  R. Reynolds,et al.  The NCEP/NCAR 40-Year Reanalysis Project , 1996, Renewable Energy.

[35]  M. G. Manoj,et al.  Absorbing aerosols facilitate transition of Indian monsoon breaks to active spells , 2011 .

[36]  N. Middleton,et al.  Saharan dust storms: nature and consequences , 2001 .

[37]  Oleg Dubovik,et al.  Global aerosol optical properties and application to Moderate Resolution Imaging Spectroradiometer aerosol retrieval over land , 2007 .

[38]  Ramesh P. Singh,et al.  Contrasting Aerosol Trends Over South Asia During the Last Decade Based on MODIS Observations , 2011 .

[39]  H. McMahon.  Recent Survey and Exploration in Seistan , 1906 .

[40]  Michael Schulz,et al.  Global dust model intercomparison in AeroCom phase I , 2011 .

[41]  P. Vinayachandran,et al.  Droughts of the Indian summer monsoon: Role of clouds over the Indian Ocean , 2003 .

[42]  S. S. Prijith,et al.  Role of dynamics in the advection of aerosols over the Arabian Sea along the west coast of peninsular India during pre-monsoon season: A case study based on satellite data and regional climate model , 2011 .

[43]  Seyed Mohammad Zamanzadeh,et al.  Characteristics of TSP Loads during the Middle East Springtime Dust Storm (MESDS) in Western Iran , 2014, Arabian Journal of Geosciences.

[44]  M. Sharifikia.  Environmental challenges and drought hazard assessment of Hamoun Desert Lake in Sistan region, Iran, based on the time series of satellite imagery , 2012, Natural Hazards.

[45]  Dimitris G. Kaskaoutis,et al.  Temporal changes of particulate concentration in the ambient air over the city of Zahedan, Iran , 2013, Air Quality, Atmosphere & Health.

[46]  Jean-François Léon,et al.  Mineral dust sources in the surroundings of the north Indian Ocean , 2003 .

[47]  T. Takemura,et al.  Aerosol optical depth, physical properties and radiative forcing over the Arabian Sea , 2006 .

[48]  A. Sturman,et al.  Low level jet intensification by mineral dust aerosols , 2013 .

[49]  Toshihiko Takemura,et al.  A simulation of the global distribution and radiative forcing of soil dust aerosols at the Last Glacial Maximum , 2009 .

[50]  P. Rasch,et al.  Short-term modulation of Indian summer monsoon rainfall by West Asian dust , 2014 .