1
|
Relative Merits of Optimal Estimation and Non-Linear Retrievals of Sea-Surface Temperature from MODIS. REMOTE SENSING 2022. [DOI: 10.3390/rs14092249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We compared the results of an Optimal Estimation (OE) based approach for the retrieval of the skin sea surface temperature (SSTskin) with those of the traditional non-linear sea surface temperature (NLSST) algorithm. The retrievals were from radiance measurements in two infrared channels of the Moderate Resolution Imaging Spectroradiometer (MODIS) on the NASA satellite Aqua. The OE used a reduced state vector of SST and total column water vapor (TCWV). The SST and atmospheric profiles of temperature and humidity from ERA5 provided prior knowledge, and we made reasonable assumptions about the variance of these fields. An atmospheric radiative transfer model was used as the forward model to simulate the MODIS measurements. The performances of the retrieval approaches were assessed by comparison with in situ measurements. We found that the OESST reduces the satellite–in situ bias, but mostly for retrievals with an already small bias between in situ and the prior SST. The OE approach generally fails to improve the SST retrieval when that difference is large. In such cases, the NLSST often provides a better estimate of the SST than the OE. The OESST also underperforms NLSST in areas that include large horizontal SST gradients.
Collapse
|
2
|
15-Year Analysis of Direct Effects of Total and Dust Aerosols in Solar Radiation/Energy over the Mediterranean Basin. REMOTE SENSING 2022. [DOI: 10.3390/rs14071535] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The direct radiative effects of atmospheric aerosols are essential for climate, as well as for other societal areas, such as the energy sector. The goal of the present study is to exploit the newly developed ModIs Dust AeroSol (MIDAS) dataset for quantifying the direct effects on the downwelling surface solar irradiance (DSSI), induced by the total and dust aerosol amounts, under clear-sky conditions and the associated impacts on solar energy for the broader Mediterranean Basin, over the period 2003–2017. Aerosol optical depth (AOD) and dust optical depth (DOD) derived by the MIDAS dataset, along with additional aerosol and dust optical properties and atmospheric variables, were used as inputs to radiative transfer modeling to simulate DSSI components. A 15-year climatology of AOD, DOD and clear-sky global horizontal irradiation (GHI) and direct normal irradiation (DNI) was derived. The spatial and temporal variability of the aerosol and dust effects on the different DSSI components was assessed. Aerosol attenuation of annual GHI and DNI were 1–13% and 5–47%, respectively. Over North Africa and the Middle East, attenuation by dust was found to contribute 45–90% to the overall attenuation by aerosols. The GHI and DNI attenuation during extreme dust episodes reached 12% and 44%, respectively, over particular areas. After 2008, attenuation of DSSI by aerosols became weaker mainly because of changes in the amount of dust. Sensitivity analysis using different AOD/DOD inputs from Copernicus Atmosphere Monitoring Service (CAMS) reanalysis dataset revealed that using CAMS products leads to underestimation of the aerosol and dust radiative effects compared to MIDAS, mainly because the former underestimates DOD.
Collapse
|
3
|
Meng X, Yao F, Zhang J, Liu Q, Liu Q, Shi L, Zhang D. Impact of dust deposition on phytoplankton biomass in the Northwestern Pacific: A long-term study from 1998 to 2020. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 813:152536. [PMID: 34954163 DOI: 10.1016/j.scitotenv.2021.152536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 12/11/2021] [Accepted: 12/15/2021] [Indexed: 06/14/2023]
Abstract
Dust deposition can supply nutrients to the ocean and affect phytoplankton growth. However, the impact of dust deposition on phytoplankton biomass in varying trophic regions remains poorly evaluated. The Northwestern Pacific is located in the downwind area of East Asian dust and includes eutrophic regions (Yellow Sea, YS; East China Sea, ECS), high-nutrient low-chlorophyll waters (subarctic Northwestern Pacific, SNWP) and low-nutrient low-chlorophyll waters (Northwestern Pacific subtropical gyre, NWPSG), which is an ideal region to explore the spatial heterogeneity of the dust fertilization effect. Here, the distribution and variation of dust deposition, high dust deposition events (HDDE) and Chlorophyll-a concentration (Chl-a, mg m-3) in the Northwestern Pacific during spring from 1998 to 2020 were investigated. The differences in the response of phytoplankton biomass (using Chl-a as a proxy) to HDDE in the YS, the ECS, the SNWP and the NWPSG were explored. Our results indicated that a large amount of dust was deposited into the Northwest Pacific during spring, resulting in numerous HDDE. The HDDE could stimulate the increase of phytoplankton biomass in the whole area of the Northwestern Pacific during spring. The response probabilities of Chl-a to HDDE were most significant (~80%) in the SNWP and the duration of response was the longest, even lasting for up to 40 days. While the response probabilities of Chl-a to HDDE were lowest in the YS and ECS (~65%), increasing from north to south, and most of the responses were less than 20 days. The response of Chl-a to HDDE was also detected in NWPSG, confirming the dust fertilization effect in oligotrophic waters, with response probabilities of 70% and duration less than 30 days. Overall, this study provides a more comprehensive understanding of the differences of phytoplankton response to dust deposition in varying trophic regions.
Collapse
Affiliation(s)
- Xianglei Meng
- College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Fengmei Yao
- College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China; The Key Laboratory of Computational Geodynamics, Chinese Academy of Sciences, Beijing, China.
| | - Jiahua Zhang
- College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China; Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China.
| | - Quan Liu
- College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China; Max-Planck-Institute for Meteorology, 20146 Hamburg, Germany
| | - Qi Liu
- College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Lamei Shi
- Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China; College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Da Zhang
- Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China; College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China
| |
Collapse
|
4
|
Yang Z, Lü F, Zhang H, Wang W, Xu X, Shao L, Che Z, Lu B, Ye J, He P. A neglected transport of plastic debris to cities from farmland in remote arid regions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 807:150982. [PMID: 34656567 DOI: 10.1016/j.scitotenv.2021.150982] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 07/21/2021] [Accepted: 10/10/2021] [Indexed: 06/13/2023]
Abstract
Although microplastics have been investigated in terrestrial environments, the occurrence and transport of microplastics in semiarid regions with serious wind erosion are still limited. We investigated plastic debris, including macroplastics (>5 mm) and microplastics (50 μm to 5 mm), from twenty semiarid farmlands and then developed a mass flux model to calculate the quantities of plastic debris transport by wind erosion. Finally, the spatial extent of microplastic deposition was estimated. The average abundance of macroplastics increased with duration of mulching film use, whereas the abundance of microplastics did not change significantly (p > 0.05). Moreover, the highest abundance of microplastics among samples was from the farmland using greenhouse, which suggests that wind erosion played an essential role in retention of plastic debris. Besides, the enrichment ratio (ER) which depends on the shape of microplastics is identified to be a key indicator of the mass flux model. The results showed that 6.91-38.11 kg/ha of plastic debris was released by wind in the 25th year after film application, with 6.14 n/m2 of microplastics settling in February in Xi'an, which is 690 km away from the source.
Collapse
Affiliation(s)
- Zhan Yang
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, PR China
| | - Fan Lü
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Hua Zhang
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Wei Wang
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, PR China
| | - Xiangyu Xu
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, PR China
| | - Liming Shao
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, PR China
| | - Zongxian Che
- Institute of Soil, Fertilizer and Water-saving Agriculture, Gansu Academy of Agricultural Sciences, Lanzhou 730070, PR China
| | - Binglin Lu
- Institute of Soil, Fertilizer and Water-saving Agriculture, Gansu Academy of Agricultural Sciences, Lanzhou 730070, PR China
| | - Jianfeng Ye
- Water Research Institute, Shanghai Academy of Environmental Sciences, Shanghai 200233, PR China
| | - Pinjing He
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, PR China.
| |
Collapse
|
5
|
Sensitivity of Summertime Convection to Aerosol Loading and Properties in the United Arab Emirates. ATMOSPHERE 2021. [DOI: 10.3390/atmos12121687] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The Weather Research and Forecasting (WRF) model is used to investigate convection–aerosol interactions in the United Arab Emirates (UAE) for a summertime convective event. Both an idealized and climatological aerosol distributions are considered. The convection on 14 August 2013 was triggered by the low-level convergence of the cyclonic circulation associated with the Arabian Heat Low (AHL) and the daytime sea-breeze circulation. Numerical experiments reveal a high sensitivity to aerosol properties. In particular, replacing 20% of the rural aerosols by carbonaceous particles has a comparable impact on the surface radiative fluxes to increasing the aerosol loading by a factor of 10. In both cases, the UAE-averaged net shortwave flux is reduced by ~90 W m−2 while the net longwave flux increases by ~51 W m−2. However, when the aerosol composition is changed, WRF generates 20% more precipitation than when the aerosol loading is increased, due to a broader and weaker AHL. The surface downward and upward shortwave and upward longwave radiation fluxes are found to scale linearly with the aerosol loading. An increase in the amount of aerosols also leads to drier conditions and a delay in the onset of convection due to changes in the AHL.
Collapse
|
6
|
Huang J, Kang S, Yin R, Ram K, Liu X, Lu H, Guo J, Chen S, Tripathee L. Desert dust as a significant carrier of atmospheric mercury. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 267:115442. [PMID: 33254682 DOI: 10.1016/j.envpol.2020.115442] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 08/14/2020] [Accepted: 08/14/2020] [Indexed: 06/12/2023]
Abstract
The atmospheric circulation plays a critical role in the global transport and deposition of atmospheric pollutants such as mercury (Hg). Desert dust emissions contribute to nearly 60-95% of the global dust budget and thus, desert dust may facilitate atmospheric Hg transport and deposition to the downwind regions worldwide. The role of desert dust in biogeochemical cycling of Hg, however, has not been well recognized by the Hg research community. In this study, we measured the concentration of particulate bound Hg (HgP) in total suspended particulate (TSP) collected from China's largest desert, Taklimakan Desert, between 2013 and 2017. The results show that HgP concentrations over the Taklimakan Desert atmosphere are remarkably higher than those observed from background sites in China and are even comparable to those measured in most of the Chinese metropolitan cities. Moreover, HgP concentrations in the Taklimakan Desert exhibit a distinct seasonal pattern peaking during dust storm outbreak periods in spring and summer (March to August). A preliminary estimation demonstrates that export of total Hg associated with atmospheric dust from the Taklimakan Desert could be 59.7 ± 60.3 (1SD) Mg yr-1. The unexpectedly high HgP concentrations during duststorms, together with consistent seasonal pattern of Hg revealed from the snow/ice, clearly demonstrate that Asian desert dust could act as a significant carrier of atmospheric Hg to the cryosphere of Western China and even can have further global reach.
Collapse
Affiliation(s)
- Jie Huang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Shichang Kang
- State Key Laboratory of Cryospheric Science, Northeast Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing, 100101, China; University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Runsheng Yin
- State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550002, China
| | - Kirpa Ram
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China; Institute of Environment and Sustainable Development, Banaras Hindu University, Varanasi, 221005, India
| | - Xinchun Liu
- Key Laboratory of Tree-ring Physical and Chemical Research of China Meteorological Administration, Institute of Desert Meteorology, China Meteorological Administration, Urumqi, 830002, China
| | - Hui Lu
- Key Laboratory of Tree-ring Physical and Chemical Research of China Meteorological Administration, Institute of Desert Meteorology, China Meteorological Administration, Urumqi, 830002, China
| | - Junming Guo
- State Key Laboratory of Cryospheric Science, Northeast Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Siyu Chen
- College of Atmospheric Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Lekhendra Tripathee
- State Key Laboratory of Cryospheric Science, Northeast Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| |
Collapse
|
7
|
|
8
|
Zhang Y, Bao F, Li M, Chen C, Zhao J. Nitrate-Enhanced Oxidation of SO 2 on Mineral Dust: A Vital Role of a Proton. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:10139-10145. [PMID: 31389234 DOI: 10.1021/acs.est.9b01921] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Heterogeneous oxidation of SO2 on mineral dust is a significant source of sulfate in the atmosphere. Given that a large fraction of nitrate is deposited on the mineral aerosols, the determination of the effect of nitrate on the SO2 oxidation on mineral dust and its in-depth mechanism are much desired. In this work, we report nitrate-enhanced SO2 oxidation on authentic mineral dust. By comparing the SO2 uptake behaviors on Arizona test dust (ATD, a typical proxy of mineral dust) with or without nitrate, we found that although nitrate hinders the initial SO2 uptake, it substantially accelerates SO2 uptake and oxidation after a pronounced induction period. In other words, a hindering-then-accelerating feature in the SO2 uptake profile was observed on nitrate-containing ATD (N-ATD) particles. In addition, HONO was released in the accelerating period as the reduction product of nitrate. The accumulation of protons (H+) from SO2 oxidation during the induction period plays a key role in the acceleration of SO2 oxidation. Our work suggests that the nitrate-participating SO2 oxidation on mineral dust can be one of the important contributions of the sulfate source in the atmosphere.
Collapse
Affiliation(s)
- Yue Zhang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry , The Chinese Academy of Sciences , Beijing 100190 , China
- University of Chinese Academy of Sciences , Beijing 100049 , P. R. China
| | - Fengxia Bao
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry , The Chinese Academy of Sciences , Beijing 100190 , China
- University of Chinese Academy of Sciences , Beijing 100049 , P. R. China
| | - Meng Li
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry , The Chinese Academy of Sciences , Beijing 100190 , China
- University of Chinese Academy of Sciences , Beijing 100049 , P. R. China
| | - Chuncheng Chen
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry , The Chinese Academy of Sciences , Beijing 100190 , China
- University of Chinese Academy of Sciences , Beijing 100049 , P. R. China
| | - Jincai Zhao
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry , The Chinese Academy of Sciences , Beijing 100190 , China
- University of Chinese Academy of Sciences , Beijing 100049 , P. R. China
| |
Collapse
|
9
|
Spring 2018 Asian Dust Events: Sources, Transportation, and Potential Biogeochemical Implications. ATMOSPHERE 2019. [DOI: 10.3390/atmos10050276] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The input of aeolian mineral dust to the oceans is regarded as the major source in supplying bioavailable iron for phytoplankton growth. Severe dust events swept over East Asia during the 26 March to the 4 April 2018, decreasing air quality to hazardous levels, with maximum PM10 mass concentrations above 3000 μg m−3 in northern China. Based on a comprehensive approach that combines multiple satellite measurements, ground observations, and model simulation, we revealed that two severe Asian dust events originating from the Taklimakan and Gobi deserts on 26 March and 1 April, were transported through northern China and the East/Japan Sea, to the North Pacific Ocean by westerly wind systems. Transportation pathways dominated by mineral dust aerosols were observed at altitudes of 2–7 km in the source regions, and then ascending to 3–10 km in the North Pacific Ocean, with relatively denser dust plumes within the second dust episode than there were during the first. Our results suggest that mineral dust emitted from the Taklimakan and Gobi deserts could increase ocean primary productivity in the North Pacific Ocean by up to ~50%, compared to average conditions. This emphasizes the potential importance of the deposition of Asian mineral dust over the North Pacific Ocean for enhancing the biological pump.
Collapse
|
10
|
Conny JM, Willis RD, Ortiz-Montalvo DL. Analysis and Optical Modeling of Individual Heterogeneous Asian Dust Particles Collected at Mauna Loa Observatory. JOURNAL OF GEOPHYSICAL RESEARCH. ATMOSPHERES : JGR 2019; 124:10.1029/2018jd029387. [PMID: 32166055 PMCID: PMC7067279 DOI: 10.1029/2018jd029387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 02/07/2019] [Indexed: 06/10/2023]
Abstract
We have determined optical properties of heterogeneous particles from aerosol samples collected at Hawaii's Mauna Loa Observatory. Back trajectories, satellite imagery, and composition differences among particles from scanning electron microscopy revealed a subset of particles with dolomite or calcite that likely came from Asia. Using focused ion-beam tomography and the discrete dipole approximation, we show how small amounts of an iron phase (oxide or carbonate), or in one case soot, affected extinction and scattering compared with particles of neat dolomite or calcite. We show how particles exhibit a range scattering values due to varying orientations of the inclusion phases. Extinction efficiencies for the heterogeneous particles with dolomite (3.47) and calcite (3.36) were 19% to 21% lower than extinction for marine background air particles (3.72). Extinction for the Asian dust was, however, generally higher than for the neat particles. Compared to iron carbonate, the presence of an absorbing iron oxide affected scattering in Asian dust particles even at the low oxide concentrations studied here (0.6% to 8.1%). Scattering efficiency decreased by <1% with a 1% increase in hematite but by 2% to 5% with magnetite. Asian dust scattered light strongly forward, but backscattering was 56% larger than for the marine background air particles. Backscattering in the Asian dust was also larger with magnetite than hematite. Single scattering albedo for Asian dust with hematite, magnetite, or soot averaged 0.96 ± 0.06 ( x ¯ ± s , n = 19 ) but was as low as 0.72 with a magnetite mass of 5.8%.
Collapse
Affiliation(s)
- Joseph M Conny
- Materials Measurement Science Division, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - Robert D Willis
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA (retired)
| | - Diana L Ortiz-Montalvo
- Materials Measurement Science Division, National Institute of Standards and Technology, Gaithersburg, MD, USA
| |
Collapse
|
11
|
A Systematic Review of Global Desert Dust and Associated Human Health Effects. ATMOSPHERE 2016. [DOI: 10.3390/atmos7120158] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
|
12
|
Goudie AS. Desert dust and human health disorders. ENVIRONMENT INTERNATIONAL 2014; 63:101-13. [PMID: 24275707 DOI: 10.1016/j.envint.2013.10.011] [Citation(s) in RCA: 210] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Revised: 10/06/2013] [Accepted: 10/17/2013] [Indexed: 05/18/2023]
Abstract
Dust storms may originate in many of the world's drylands and have an effect not only on human health in the drylands themselves but also in downwind environments, including some major urban centres, such as Phoenix, Kano, Athens, Madrid, Dubai, Jedda, Tehran, Jaipur, Beijing, Shanghai, Seoul, Taipei, Tokyo, Sydney, Brisbane and Melbourne. In some parts of the world dust storms occur frequently throughout the year. They can transport particulate material, pollutants, and potential allergens over thousands of km from source. The main sources include the Sahara, central and eastern Asia, the Middle East, and parts of the western USA. In some parts of the world, though not all, the frequency of dust storms is changing in response to land use and climatic changes, and in such locations the health implications may become more severe. Data on the PM10 and P2.5 loadings of dust events are discussed, as are various pollutants (heavy metals, pesticides, etc.) and biological components (spores, fungi, bacteria, etc.). Particulate loadings can far exceed healthy levels. Among the human health effects of dust storms are respiratory disorders (including asthma, tracheitis, pneumonia, allergic rhinitis and silicosis) cardiovascular disorders (including stroke), conjunctivitis, skin irritations, meningococcal meningitis, valley fever, diseases associated with toxic algal blooms and mortality and injuries related to transport accidents.
Collapse
Affiliation(s)
- Andrew S Goudie
- School of Geography and the Environment, University of Oxford, South Parks Road, Oxford OX1 3QY, United Kingdom.
| |
Collapse
|
13
|
Fiedler S, Schepanski K, Heinold B, Knippertz P, Tegen I. Climatology of nocturnal low-level jets over North Africa and implications for modeling mineral dust emission. JOURNAL OF GEOPHYSICAL RESEARCH. ATMOSPHERES : JGR 2013; 118:6100-6121. [PMID: 25893154 PMCID: PMC4394707 DOI: 10.1002/jgrd.50394] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Accepted: 04/10/2013] [Indexed: 05/29/2023]
Abstract
[1] This study presents the first climatology for the dust emission amount associated with Nocturnal Low-Level Jets (NLLJs) in North Africa. These wind speed maxima near the top of the nocturnal boundary layer can generate near-surface peak winds due to shear-driven turbulence in the course of the night and the NLLJ breakdown during the following morning. The associated increase in the near-surface wind speed is a driver for mineral dust emission. A new detection algorithm for NLLJs is presented and used for a statistical assessment of NLLJs in 32 years of ERA-Interim reanalysis from the European Centre for Medium-Range Weather Forecasts. NLLJs occur in 29% of the nights in the annual and spatial mean. The NLLJ climatology shows a distinct annual cycle with marked regional differences. Maxima of up to 80% NLLJ frequency are found where low-level baroclinicity and orographic channels cause favorable conditions, e.g., over the Bodélé Depression, Chad, for November-February and along the West Saharan and Mauritanian coast for April-September. Downward mixing of NLLJ momentum to the surface causes 15% of mineral dust emission in the annual and spatial mean and can be associated with up to 60% of the total dust amount in specific areas, e.g., the Bodélé Depression and south of the Hoggar-Tibesti Channel. The sharp diurnal cycle underlines the importance of using wind speed information with high temporal resolution as driving fields for dust emission models. Citation: Fiedler, S., K. Schepanski, B. Heinold, P. Knippertz, and I. Tegen (2013), Climatology of nocturnal low-level jets over North Africa and implications for modeling mineral dust emission, J. Geophys. Res. Atmos., 118, 6100-6121, doi:10.1002/jgrd.50394.
Collapse
Affiliation(s)
- S Fiedler
- School of Earth and Environment, University of Leeds Leeds, UK
| | - K Schepanski
- School of Earth and Environment, University of Leeds Leeds, UK ; Now at Leibniz Institute for Tropospheric Research Leipzig, Germany
| | - B Heinold
- School of Earth and Environment, University of Leeds Leeds, UK ; Now at Leibniz Institute for Tropospheric Research Leipzig, Germany
| | - P Knippertz
- School of Earth and Environment, University of Leeds Leeds, UK
| | - I Tegen
- Leibniz Institute for Tropospheric Research Leipzig, Germany
| |
Collapse
|
14
|
Mineral dust photochemistry induces nucleation events in the presence of SO2. Proc Natl Acad Sci U S A 2012; 109:20842-7. [PMID: 23213230 DOI: 10.1073/pnas.1212297109] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Large quantities of mineral dust particles are frequently ejected into the atmosphere through the action of wind. The surface of dust particles acts as a sink for many gases, such as sulfur dioxide. It is well known that under most conditions, sulfur dioxide reacts on dust particle surfaces, leading to the production of sulfate ions. In this report, for specific atmospheric conditions, we provide evidence for an alternate pathway in which a series of reactions under solar UV light produces first gaseous sulfuric acid as an intermediate product before surface-bound sulfate. Metal oxides present in mineral dust act as atmospheric photocatalysts promoting the formation of gaseous OH radicals, which initiate the conversion of SO(2) to H(2)SO(4) in the vicinity of dust particles. Under low dust conditions, this process may lead to nucleation events in the atmosphere. The laboratory findings are supported by recent field observations near Beijing, China, and Lyon, France.
Collapse
|
15
|
Malek MA, Kim B, Jung HJ, Song YC, Ro CU. Single-Particle Mineralogy of Chinese Soil Particles by the Combined Use of Low-Z Particle Electron Probe X-ray Microanalysis and Attenuated Total Reflectance-FT-IR Imaging Techniques. Anal Chem 2011; 83:7970-7. [DOI: 10.1021/ac201956h] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Md Abdul Malek
- Department of Chemistry, Inha University, 253, Yonghyun-dong, Nam-gu, Incheon 402-751, Korea
| | - BoWha Kim
- Department of Chemistry, Inha University, 253, Yonghyun-dong, Nam-gu, Incheon 402-751, Korea
| | - Hae-Jin Jung
- Department of Chemistry, Inha University, 253, Yonghyun-dong, Nam-gu, Incheon 402-751, Korea
| | - Young-Chul Song
- Department of Chemistry, Inha University, 253, Yonghyun-dong, Nam-gu, Incheon 402-751, Korea
| | - Chul-Un Ro
- Department of Chemistry, Inha University, 253, Yonghyun-dong, Nam-gu, Incheon 402-751, Korea
| |
Collapse
|