Spatio-temporal variability of dust aerosols over the Sistan region in Iran based on satellite observations

Rashki, Alireza; Kaskaoutis, Dimitris G.; Eriksson, P.G.; Rautenbach, Christo; Flamant, Cyrille; Vishkaee, Farhad Abdi

doi:10.1007/s11069-013-0927-0

Cited by 53 publications

(23 citation statements)

References 75 publications

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“…Over the regions of Arabian and Red seas and the Gulf of Aden, which also experience desert dust transport, larger g aer values appear in the period from March to September, with a maximum in August (locally as high as 0.75-0.76). This seasonal behavior is in line with intra-annual changes of dust production over the Arabian Peninsula indicated by MODIS Ångström exponent (AE) and Deep Blue aerosol optical depth data (Ginoux et al, 2012), as well as over southwest Asia through in situ data (Rashki et al, 2012), aerosol index from various platforms and MODIS Deep Blue AOD data (Rashki et al, 2014). Indeed, the production of dust there is relatively poor in winter, increases in March and April and becomes maximum in June and July (Prospero et al, 2002).…”

Section: B Korras-carraca Et Al: Modis Aerosol Asymmetry Parametsupporting

confidence: 79%

The regime of aerosol asymmetry parameter over Europe, the Mediterranean and the Middle East based on MODIS satellite data: evaluation against surface AERONET measurements

et al. 2015

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Abstract. Atmospheric particulates are a significant forcing agent for the radiative energy budget of the Earthatmosphere system. The particulates' interaction with radiation, which defines their climate effect, is strongly dependent on their optical properties. In the present work, we study one of the most important optical properties of aerosols, the asymmetry parameter (g aer ), over sea surfaces of the region comprising North Africa, the Arabian Peninsula, Europe, and the Mediterranean Basin. These areas are of great interest, because of the variety of aerosol types they host, both anthropogenic and natural. Using satellite data from the collection 051 of MODIS (Moderate Resolution Imaging Spectroradiometer, Terra and Aqua), we investigate the spatiotemporal characteristics of the asymmetry parameter. We generally find significant spatial variability, with larger values over regions dominated by larger size particles, e.g., outside the Atlantic coasts of northwestern Africa, where desert-dust outflow takes place. The g aer values tend to decrease with increasing wavelength, especially over areas dominated by small particulates. The intra-annual variability is found to be small in desert-dust areas, with maximum values during summer, while in all other areas larger values are reported during the cold season and smaller during the warm. Significant intra-annual and inter-annual variability is observed around the Black Sea. However, the inter-annual trends of g aer are found to be generally small.Although satellite data have the advantage of broad geographical coverage, they have to be validated against reliable surface measurements. Therefore, we compare satellitemeasured values with g aer values measured at 69 stations of the global surface AERONET (Aerosol Robotic Network), located within our region of interest. This way, we provide some insight on the quality and reliability of MODIS data. We report generally better agreement at the wavelength of 860 nm (correlation coefficient R up to 0.47), while at all wavelengths the results of the comparison were better for spring and summer.

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Section: B Korras-carraca Et Al: Modis Aerosol Asymmetry Parametsupporting

confidence: 79%

The regime of aerosol asymmetry parameter over Europe, the Mediterranean and the Middle East based on MODIS satellite data: evaluation against surface AERONET measurements

et al. 2015

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“…Within these areas, dust activity is also a prominent feature in spring, but is significantly weakened in autumn and winter. The seasonal variations of dust outbreaks over the Sistan Basin have been also highlighted in the recent work of Rashki et al (2014) using different satellite datasets. Similar to the present study, they have identified a peak aerosol load in summer, but substantially lower values in winter.…”

Section: Seasonal and Monthly Variationsmentioning

confidence: 82%

Temporal variations in the frequency and concentration of dust events over Iran based on surface observations

2015

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Using surface meteorological records of a 20-year period from 1991 to 2010, temporal variations in the frequency and concentration of transported dust events over Iran are investigated. Five regions of frequent dust events are identified. In the order of importance, these areas are the Khuzestan Plain, the coastal plain of the Persian Gulf, west of Iran, Tabas and Sistan. The first three areas create a belt of high frequency of dust events along the western foothills of the Zagros Mountains. The Khuzestan Plain is the area with the highest frequency of dust events, over which dust laden air is almost permanently present in summer, while the coastal plain of the Persian Gulf is the second most affected area. These two areas, along with west of Iran, are mostly influenced by transported dust from sources outside of Iran, while Tabas and Sistan are mostly influenced by arid lands in the interior of Iran. In contrast, the southern coastal strip of the Caspian Sea is the area with the least frequent dust episodes. Throughout Iran, the frequency of dust events strengthens in spring, peaks in summer and significantly weakens in autumn and winter, with the least observed frequency in winter. Significant monthly variations of the frequency of dust events were also identified, with the most and least frequencies in July and December, respectively. In terms of long-term frequency of dust events, our observational analyses show an overall rising trend of the frequency of Iran's dust events in recent years, predominantly attributed to increasingly frequent dust outbreaks in Iraq due to human intervention.

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“…OMI's advantage for aerosol characterization from space is the availability of measurements in the near-UV region for which the retrieval technique of aerosol sensing works equally well over all land and water surfaces because of the low UV surface albedo of all ice and snow-free terrestrial surfaces (Torres et al 2007). The dependence on altitude of the AI limits its usage for comparison of the relative strengths of dust sources in different meteorological regimes (Hsu et al 1999); however, the AI over the Aral Sea basin should provide a rough measurement of the relative dust aerosol concentrations (Hsu et al 1999;Rashki et al 2014;Washington et al 2003). AI is positive for absorbing aerosols (dust and smoke particles) and negative for non-absorbing aerosols (Sreekanth 2014a, b).…”

Section: Datasets and Analysesmentioning

confidence: 99%

Temporal Variability and Potential Diffusion Characteristics of Dust Aerosol Originating from the Aral Sea Basin, Central Asia

Abuduwaili

et al. 2016

Water Air Soil Pollut

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The drastic desiccation of the Aral Sea has led to severe desertification of the former lake areas. Dust storms occur frequently, causing regional environmental degradation of the Aral basin and a serious ecological disaster. Knowledge of the temporal variability in dust emissions and the potential diffusion characteristics of dust aerosol originating from the Aral Sea basin in recent years are, however, lacking. To address this knowledge gap, we studied the interannual and intraannual changes in dust aerosol from the Aral Sea basin and its potentially seasonal diffusion characteristics from 2005 to 2013 using Ozone Monitoring Instrument (OMI) aerosol data (2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013) and the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model. Results show that the OMI aerosol index (AI) annual mean, standard deviation, median, and maximum values exhibit a strong increasing trend because of the continuous decrease in the water level since 2005. The annually mean OMI AI increases to 1.47 by 2013. Peak AI values are recorded in spring (March-May) and early winter (November-January of the following year), indicating notifying seasonal differences. The potential distance and height of air parcel trajectories to the northeast are greater than those to the west and south, whereas the air parcel trajectory proportion of the former is lower than that of the latter. The potential transport distance of dust aerosol to the northeast is greatest in spring and winter. This transport distance is less in autumn, with the minimum observed in summer. Dust transport distance to the west and south in different seasons is not significantly different. The present results may help in further understanding the emission, long-range transport, and deposition of dust from the dry lake bed of the Aral Sea as well as providing a motivation for the sensible use and protection of these tail-end lakes.

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Spatio-temporal variability of dust aerosols over the Sistan region in Iran based on satellite observations

Cited by 53 publications

References 75 publications

The regime of aerosol asymmetry parameter over Europe, the Mediterranean and the Middle East based on MODIS satellite data: evaluation against surface AERONET measurements

The regime of aerosol asymmetry parameter over Europe, the Mediterranean and the Middle East based on MODIS satellite data: evaluation against surface AERONET measurements

Temporal variations in the frequency and concentration of dust events over Iran based on surface observations

Temporal Variability and Potential Diffusion Characteristics of Dust Aerosol Originating from the Aral Sea Basin, Central Asia

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