Investigation of Two Severe Shamal Dust Storms and the Highest Dust Frequencies in the South and Southwest of Iran

Abstract

Dust storms create some of the most critical air quality problems in the world; the Middle East, located in the dust belt, suffers substantially from dust storms. Iran, as a country in the Middle East, is affected by dust storms from multiple internal and external sources that mostly originate from deserts in Iraq and Syria (especially the Mesopotamia region). To determine the highest dust loadings in the south and west of Iran, dust frequencies were investigated in the eight most polluted stations in the west, southwest, and southern Iran for a period of 21 years from 2000 to 2021. During the study’s duration, the dust frequency was much higher from 2008 to 2012, which coincided with severe droughts reported in Iraq and Syria; from which, we investigated two severe dust storms (as well as the dust sources and weather condition effects) that took place on 15–17 September 2008 and 1–3 June 2012; we used secondary data from ground measurement stations, and satellite and modeling products. In both cases, horizontal visibility was reduced to less than 1 km at most weather stations in Iran. The measured PM10 in the first case reached 834 μg m−3 at Ilam station in west Iran and the Iran–Iraq borders while the measured PM10 in the second case reached 4947 μg m−3 at Bushehr station in the northern shore of the Persian Gulf. The MODIS true color images and MODIS AOD detected the dust mass over Iraq, southern Iran, and Saudi Arabia in both cases; the AOD value reached 4 in the first case and 1.8 in the second case over the Persian Gulf. During these two severe dust storms, low-level jets were observed at 930 hPa atmospheric levels in north Iraq (2008 case) and south Iraq (2012 case). The output of the NAPPS model and CALIPSO satellite images show that the dust rose to higher than 5 km in these dust storm cases, confirming the influence of Shamal wind on the dust storm occurrences.

Optimization and Evaluation of the Weather Research and Forecasting (WRF) Model for Wind Energy Resource Assessment and Mapping in Iran

“…All other parts of Iran present much lower wind speeds, which are generally increased along the Zagros and Alborz mountain ranges, since stronger winds occur at higher altitudes. The Iranian Plateau and coastal areas are characterized by rather weak winds, as well as the southwest part of Iran (Khuzestan Province), which is highly affected by Shamal dust storms mostly during the warm period of the year [108][109][110]. On an annual mean basis, the effect of "Qibla wind" [103] over the central Iranian Plateau seems to have a rather limited impact on the wind regime over the region.…”

CALIOP-Based Evaluation of Dust Emissions and Long-Range Transport of the Dust from the Aral−Caspian Arid Region by 3D-Source Potential Impact (3D-SPI) Method

“…Thermal low-pressure systems over low topographic areas and the high-pressure Caspian Sea, along with intense surface winds over the dust sources caused the dust outbreaks and transport over Iran in summer [145]. Many dust storms in west, SW, and NW Iran were driven by the Shamal wind in summer [146] and frontal system in winter [147][148][149]. In other seasons, the east (Khorasan Province) and west (Western Azerbaijan Province; see [145]) of Iran were very often subject to the influence of ACAR air.…”

“…In the territory of Iran, the autumn contribution of ACAR-EL was quite uniform (0.03-0.05), while the impact of ACAR-TL was higher in the western and southern parts of the country (0.03-0.05) compared with the east and north of Iran (0.02-0.03). In addition, the authors of [146] showed dust storms mostly occurred from April to August and weakened after August in south, SW, and west of Iran. In addition, 84% of these areas were affected by dust storms from the Tigris-Euphrates plain in Iran and Syria, and internal dust sources had a smaller role in these hazards.…”

Investigating the Role of the Low-Level Jet in Two Winters Severe Dust Rising in Southwest Iran

“…It includes investigation of (i) surface measured reported data, (ii) satellite remote sensing data and images, (iii) dust modeling, (iv) forward and backward trajectory analysis, and (v) synoptic analysis [32][33][34]. Methods were used in the dust studies in the Middle East region to investigate dust storm generation and transportation [35][36][37][38][39]. In some cases, soil properties and vegetation cover were investigated during the dust, along with meteorological parameters such as wind speed, wind direction, precipitation, air temperature, and so on [21,[40][41][42].…”

“…This factor had an important role in growing the frequency of dust storms in the Middle East region [43][44][45]. Also, dust storms are mainly categorized into two main groups: Shamal dust storms and frontal dust storms [35,39,[46][47][48], though haboob dust storms happen minimally in this region, too [49].…”