Two extremely devastating super dust storms (SDS) hit Mongolia and Northern China in March 2021, causing many deaths and substantial economic damage. Accurate forecasting of dust storms is of great importance for avoiding or mitigating their effects. One of the most critical factors affecting dust emissions is soil moisture, but its value in desert exhibits significant uncertainty. In this study, model experiments were conducted to simulate dust emissions using four soil moisture datasets. The results were compared with observations to assess the effects of soil moisture on the dust emission strength. The Integrated Source Apportionment Method (ISAM) was used to track the dust sources and quantify the contribution from each source region to the dust load over the North China Plain (NCP), Korea peninsula, and western Japan. The results show large differences in the dust load depending on the soil moisture datasets used. The high soil moisture in the NCEP dataset results in substantial underestimation of the dust emission flux and PM10 10 concentration. Despite a minor overestimation of PM10 10 concentrations in many Northern China cities, the ERA5 dataset yields the best simulation performance. During the two SDS events, about 7.5 Mt dust was released from the deserts in Mongolia and 2.8 Mt from the deserts in China. Source apportionment indicates that the Mongolian Gobi Desert is the dominant source of PM10 10 in the NCP, Korea peninsula, and western Japan, accounting for 60 %-80 %, while Inner Mongolia contributed 10 %- 20 %.

Northern China was hit by 13 unprecedented mega dust events in spring 2023. However, a comprehensive understanding of the relative contributions of potential dust sources to dust concentrations in China remains elusive, threatening air quality, damaging ecosystems, and further complicating dust forecasting and warning efforts. The impact of five major Asian dust sources on China and its downstream regions has been accurately quantified using the Weather Research and Forecasting Model coupled with Chemistry (WRF-Chem). Notably, dust particles originating from Mongolia play a crucial role in downstream air pollution. Approximately 56% (82.7 mu g m-3) of the dust in North China originated from Mongolia, while Mongolia contributed nearly 51% (15.9 mu g m-3) of the dust in the Korean Peninsula and surroundings. In southwest China, the prevalence of dust was predominantly attributable to sources within Inner Mongolia, China (46%). Due to geographical constraints, dust in the Tibetan Plateau mainly originated from dust sources in Xinjiang, China. Topographic blocking by the Tibetan Plateau and limitations on local dust emissions are further unfavorable to the long-distance transport of dust from South Asia to downstream regions. We also highlight the importance of variation in surface soil parameters in driving frequent dust events in spring 2023. Our findings emphasize the urgent need for collaborative research and policymaking to effectively address international dust disaster mitigation.

Black carbon (BC) can be transported over long distances and is an important trigger of climate warming and glacier melting at remote high mountains and polar regions. It is normally assumed that the variation of BC flux in remote regions is dominated by its emissions. However, after a comprehensive investigation of potential influencing factors on temporal variations of BC from ice cores of the Himalayas, this short communication shows that in addition to BC emissions, contributions from dust storms and precipitation are also important (up to 56% together) in regulating the variation of BC deposition flux and concentrations derived from remote Himalayan ice core measurements. Therefore, besides BC emissions, the influence of precipitation and BC transported by dust storms should also be considered to better quantify the lifetime and behavior of BC during its long-range transport from source to sink regions as well as to quantify the climatic effects of BC over remote Himalayan glaciers.

In this study, we report on three important optical parameters, viz. absorption and scattering coefficients (b(abs), b(scat)) and single scattering abledo (SSA) based on one-year chemical-composition data collected from an urban site (Kanpur) in the Indo-Gangetic-Plain (IGP) of northern India. In addition, absorption Angstrom exponent (AAE) was also estimated in order to understand the wavelength dependence of absorption and to decipher emission sources of carbonaceous aerosols, in particular of black carbon. The absorption and scattering coefficients ranged between 8.3 to 95.2 Mm(-1) (1 Mm(-1) = 10(-6) m(-1)) and 58 to 564 Mm(-1), respectively during the study period (for n = 66; from January 2007 to March 2008) and exhibit large seasonal variability with higher values occurring in winter and lower in the summer. Single scattering albedo varied from 0.65 to 0.92 whereas ME ranged from 0.79 to 1.40 during pre-monsoon and winter seasons, respectively. The strong seasonal variability in aerosol optical properties is attributed to varying contribution from different emission sources of carbonaceous aerosols in the IGP. A case study of haze and dust events further provide information on extreme variability in aerosol optical parameters, particularly SSA, a crucial parameter in atmospheric radiative forcing estimates. (C) 2016 Elsevier B.V. All rights reserved.

Dust storm, a natural hazard, has a direct impact on daily life for a short period. Dust storms are periodic events over India, especially in northern regions. This study has been carried out to investigate the dust impacts on the aerosol characteristics over Dehradun (DDN) during pre-monsoon (March-June), 2012 using ground measurements, satellite observations and model simulations. The measurements illustrate the distinct monthly impact on the aerosol properties with maximum dust loading during May (aerosol optical depth at 500 nm (AOD(500)) = 0.72 +/- 0.18) over DDN, which is confirmed with the Terra-MODIS (AOD(550) = 0.70 +/- 0.19) measurements. The major dust loading was recorded in aerosol measurements during May at the station, which permitting to examine the influence of dust transports on the aerosol characteristics. Spectral variation of AOD and Angstrom exponent (alpha) values displayed day to day variation of aerosol during dust episodes. Analysis of aerosol types and seven-day back-trajectories reveal the transportation of desert dust during May over DDN. The Optical Properties of Aerosols and Clouds (OPAC) model was used to compute the aerosol optical properties (e.g., Single scattering albedo (SSA) and asymmetry parameter (g)) and size distribution. The high values of SSA and g are indicating the dust loading in the atmosphere during May. Aerosol volume concentration at the coarse mode (geometric mean radii (R-V) = 2.89 +/- 0.027 mu m) is found to be increased in the May, whereas decrement has been observed in the finer mode (R-V = 0.16 +/- 0.006 mu m). The aerosol direct radiative forcing (ARF) was computed using Santa Barbara Discrete Ordinate Atmospheric Radiative Transfer (SBDART) model in the shortwave (SW) region (0.25-4.00 mu m). The mean top of the atmosphere (TOA) and surface forcing come out to be -14.49 W m(-2) and -53.29 W m(-2) respectively in May. The mean net atmospheric radiative forcing (38.79 W m(-2) maximum during May) corresponds to heating rate of similar to 1.06 degrees K d(-1) in the atmosphere.

Atmospheric aerosols are important aspects of climate research due to their impact on radiative forcing. In the present study, the aerosol optical depth (ADD), the Angstrom exponent (alpha) and the single scattering albedo (SSA) over the urban region of Hyderabad, India, were examined using Sun/Sky radiometer measurements during January-December, 2008. AOD showed higher values on certain Julian days coinciding with the occurrence of wintertime dust storm events in the Gulf Region and biomass burning due to forest fires over Indian Region. The AOD values during wintertime dust event are about similar to 55% higher than those on normal days. The SSAs show positive and negative trends in alpha (R-2 = 0.71) and black carbon (BC) aerosols (R-2 = 0.44), respectively. The aerosol size distribution shows a bimodal pattern with fine (similar to 0.15 mu m) and coarse (similar to>7 mu m) mode during January-December, 2008. The MODIS AOD showed positive correlation with sky radiometer-derived AOD values (R-2 = 0.68). (C) 2011 Elsevier B.V. All rights reserved.