Climatic and Environmental Changes in the Source Areas of Dust Storms in Xinjiang, China, during the Last 50 Years

Abstract. Saharan dust has a crucial influence on the earth climate system and its emission, transport and deposition are intimately related to, e.g., wind speed, precipitation, temperature and vegetation cover. The alteration in the physical and chemical properties of Saharan dust due to environmental changes is often used to reconstruct the climate of the past. However, to better interpret possible climate changes the dust source regions need to be known. By analysing the mineralogical composition of transported or deposited dust, potential dust source areas can be inferred. Summer dust transport off northwest Africa occurs in the Saharan air layer (SAL). In continental dust source areas, dust is also transported in the SAL; however, the predominant dust input occurs from nearby dust sources with the low-level trade winds. Hence, the source regions and related mineralogical tracers differ with season and sampling location. To test this, dust collected in traps onshore and in oceanic sediment traps off Mauritania during 2013 to 2015 was analysed. Meteorological data, particle-size distributions, back-trajectory and mineralogical analyses were compared to derive the dust provenance and dispersal. For the onshore dust samples, the source regions varied according to the seasonal changes in trade-wind direction. Gibbsite and dolomite indicated a Western Saharan and local source during summer, while chlorite, serpentine and rutile indicated a source in Mauritania and Mali during winter. In contrast, for the samples that were collected offshore, dust sources varied according to the seasonal change in the dust transporting air layer. In summer, dust was transported in the SAL from Mauritania, Mali and Libya as indicated by ferroglaucophane and zeolite. In winter, dust was transported with the trades from Western Sahara as indicated by, e.g., fluellite.

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The frequency and source areas of dust storms

Aeolian Geomorphology ◽

10.4324/9780429265150-13 ◽

2020 ◽

pp. 237-259 ◽

Cited By ~ 2

Author(s):

Nicholas John Middleton ◽

Andrew S. Goudie ◽

Gordon L. Wells

Keyword(s):

Dust Storms ◽

Source Areas

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Mineral Dust Cycle

Oxford Research Encyclopedia of Environmental Science ◽

10.1093/acrefore/9780199389414.013.46 ◽

2016 ◽

Author(s):

Irina Sokolik

Keyword(s):

Atmospheric Aerosols ◽

Environmental Changes ◽

Mineral Dust ◽

Global Climate ◽

Dust Emission ◽

Northern China ◽

Dust Storms ◽

Atmospheric Composition ◽

System Response ◽

Beneficial Effects

There is scientific consensus that human activities have been altering the atmospheric composition and are a key driver of global climate and environmental changes since pre-industrial times (IPCC, 2013). It is a pressing priority to understand the Earth system response to atmospheric aerosol input from diverse sources, which so far remain one of the largest uncertainties in climate studies (Boucher et al., 2014; Forster et al., 2007). As the second most abundant component (in terms of mass) of atmospheric aerosols, mineral dust exerts tremendous impacts on Earth’s climate and environment through various interaction and feedback processes. Dust can also have beneficial effects where it deposits: Central and South American rain forests get most of their mineral nutrients from the Sahara; iron-poor ocean regions get iron; and dust in Hawaii increases plantain growth. In northern China as well as the midwestern United States, ancient dust storm deposits known as loess are highly fertile soils, but they are also a significant source of contemporary dust storms when soil-securing vegetation is disturbed. Accurate assessments of dust emission are of great importance to improvements in quantifying the diverse dust impacts.

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Substrate affinities of higher taxa and the Ordovician Radiation

Paleobiology ◽

10.1666/0094-8373(2001)027<0768:saohta>2.0.co;2 ◽

2001 ◽

Vol 27 (4) ◽

pp. 768-778 ◽

Cited By ~ 34

Author(s):

Arnold I. Miller ◽

Sean R. Connolly

Keyword(s):

Environmental Changes ◽

Late Ordovician ◽

Substrate Affinity ◽

Bivalve Molluscs ◽

Source Areas ◽

Higher Taxa ◽

Class Level ◽

Relative Affinity ◽

Substrate Affinities ◽

Global Transition

The Ordovician Radiation exhibited a global transition in dominance from the Cambrian evolutionary fauna (e.g., trilobites), to the Paleozoic and Modern faunas (e.g., articulate brachiopods and bivalve molluscs). Although its causes have yet to be determined definitively, the transition coincided with increased global tectonism. Erosion of source areas uplifted during orogenic activity increased the siliciclastic richness of marine substrates in many venues, and it has been hypothesized previously that higher taxa with affinities for siliciclastics diversified in association with these environmental changes, whereas higher taxa not exhibiting such affinities either failed to radiate or declined in diversity. Here, we provide an initial test of this substrate affinity hypothesis by evaluating the Ordovician affinities of trilobites and articulate brachiopods.Our analyses—at the class level for both trilobites and articulate brachiopods, and at the order level for orthid and strophomenid brachiopods—were based on the affinities of constituent genera for siliciclastic, carbonate, and mixed siliciclastic/carbonate settings. Individual genus affinities are calculated with a database of genus occurrences encompassing nine Ordovician paleocontinents. Using these values, we developed a standardized relative affinity (SRA) metric to compare the propensities of higher taxa, and to assess changes in relative affinities of individual higher taxa from series to series.A simple comparison of trilobites and articulate brachiopods for the Ordovician in aggregate does not appear to support the substrate affinity hypothesis: articulate brachiopods, which contributed increasingly to overall diversity through the period, exhibit an overall affinity for carbonates and an aversion to siliciclastics. However, a rather different view emerges when we consider the affinity trajectories of higher taxa through the period: articulate brachiopods exhibit a growing affinity for siliciclastics and a declining affinity for carbonates, whereas the opposite is the case among trilobites. Among constituent articulate brachiopod orders, the affinity trajectories of orthids and strophomenids mirror that of the class. Thus, the increasing dominance of articulate brachiopods in the Middle and Late Ordovician may have been linked to the affinity for siliciclastics of a diversifying subset of the group, but further investigation will be required to verify this claim.

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Dust storms, blackouts and 50°C in the shade: Exploring the Roots of Humankind with MATLAB

10.5194/egusphere-egu2020-4803 ◽

2020 ◽

Author(s):

Martin H. Trauth

Keyword(s):

Summer School ◽

Environmental Changes ◽

Homo Sapiens ◽

Single Species ◽

Dust Storms ◽

Environmental Data ◽

Data Sets ◽

Large Lakes ◽

Braided Rivers ◽

Climate Time Series

<p>Geoscientists from the University of Potsdam reconstruct environmental changes in East Africa over the past five million years. Micro-organisms such as diatoms and rotifers, clay minerals and pollen, thousands of years old, help to reconstruct large lakes and braided rivers, dense forests and hot deserts, high mountains and deep valleys. This is the habitat of our ancestors, members of a complicated family tree or network, of which only one single species, <em>Homo sapiens</em>, has survived. MATLAB is the tool of choice for analyzing these complicated and extensive data sets, extracted from up to 300 m long drill cores, from satellite images, and from the fossil remains of humans and other animals. The software is used to analyze to detect and classify important climate transitions in climate time series, to detect objects and quantify materials in microscope and satellite imagery, to predict river networks from digital terrain models, and to model lake-level fluctuations from environmental data. The advantage of MATLAB is the use of multiple methods with one single tool. Not least because of this, the software is also becoming increasingly popular in Africa, as shown by the program of an international summer school series in Africa and Germany for collecting, processing, and presenting geo-bio-information.</p>

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Uncertainty-Based Vibration/Gyro Composite Planetary Terrain Mapping

Sensors ◽

10.3390/s19122681 ◽

2019 ◽

Vol 19 (12) ◽

pp. 2681 ◽

Cited By ~ 4

Author(s):

Chengchao Bai ◽

Jifeng Guo

Keyword(s):

Environmental Changes ◽

Estimation Method ◽

Dust Storms ◽

Simulation Environment ◽

Terrain Mapping ◽

Soil Environment ◽

Reconstruction Accuracy ◽

Mapping Accuracy ◽

Accuracy Test ◽

Accurate Perception

Accurate perception of the detected terrain is a precondition for the planetary rover to perform its own mission. However, terrain measurement based on vision and LIDAR is subject to environmental changes such as strong illumination and dust storms. In this paper, considering the influence of uncertainty in the detection process, a vibration/gyro coupled terrain estimation method based on multipoint ranging information is proposed. The terrain update model is derived by analyzing the measurement uncertainty and motion uncertainty. Combined with Clearpath Jackal unmanned vehicle—the terrain mapping accuracy test based on ROS (Robot Operating System) simulation environment—indoor Optitrack auxiliary environment and outdoor soil environment was completed. The results show that the proposed algorithm has high reconstruction ability for a given scale terrain. The reconstruction accuracy in the above test environments is within 1 cm, 2 cm, and 6 cm, respectively.

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Causes and Effects of Sand and Dust Storms: What Has Past Research Taught Us? A Survey

Journal of Risk and Financial Management ◽

10.3390/jrfm14070326 ◽

2021 ◽

Vol 14 (7) ◽

pp. 326

Author(s):

Christian Opp ◽

Michael Groll ◽

Hamidreza Abbasi ◽

Mansour Ahmadi Foroushani

Keyword(s):

Past Research ◽

Dust Storms ◽

Natural Environments ◽

Dust Transport ◽

Source Areas ◽

Integrated Strategies ◽

Advantages And Disadvantages ◽

Temperature Climate ◽

Remote Sensing Techniques ◽

Low Coverage

Barren ground and sites with low coverage by vegetation (e.g., dunes, soil surfaces, dry lakes, and riverbeds) are the main source areas of sand and dust storms (SDS). The understanding of causes, processes (abrasion, deflation, transport, deposition), and influencing factors of sandy and dusty particles moving by wind both in the boundary layer and in the atmosphere are basic prerequisites to distinguish between SDS. Dust transport in the atmosphere modulates radiation, ocean surface temperature, climate, as well as snow and ice cover. The effects of airborne particles on land are varied and can cause advantages and disadvantages, both in source areas and in sink or deposition areas, with disturbances of natural environments and anthropogenic infrastructure. Particulate matter in general and SDS specifically can cause severe health problems in human respiratory and other organs, especially in children. Economic impacts can be equally devastating, but the costs related to SDS are not thoroughly studied. The available data show huge economic damages caused by SDS and by the mitigation of their effects. Management of SDS-related hazards utilizes remote sensing techniques, on-site observations, and protective measures. Integrated strategies are necessary during both the planning and monitoring of these measures. Such integrated strategies can be successful when they are developed and implemented in close cooperation with the local and regional population and stakeholders.

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Land cover-adjusted index for the former Aral Sea using Landsat images

E3S Web of Conferences ◽

10.1051/e3sconf/202122702005 ◽

2021 ◽

Vol 227 ◽

pp. 02005

Author(s):

Ilhomjon Aslanov ◽

Sayidjakhon Khasanov ◽

Yakhshimurad Khudaybergenov ◽

Michael Groll ◽

Christian Opp Ch ◽

...

Keyword(s):

Remote Sensing ◽

Environmental Changes ◽

Vegetation Indices ◽

Dust Storms ◽

Ecological Crisis ◽

Aral Sea ◽

Landsat Images ◽

Desert Ecosystems ◽

Aral Sea Basin ◽

Remote Sensing Methods

The Aral Sea was the fourth largest inland lake on the globe until 1960, with a surface area of about 68,000 km2. Mainly, the huge irrigation projects in many parts of its transboundary catchment were responsible for the catastrophic desiccation and ecological crises of the Aral Sea after second part of 20th century. Ecological crisis surrounding the Aral Sea (lake) regions is one of the critical environmental problems of Central Asia. As a result, monitoring of desertification processes and determining the aerosol concentration in the atmosphere are highly relevant for any attempts to mitigate environmental changes in the Aral Sea basin. Remote sensing is the most appropriate method for studying desertification and dust storms as it easily covers large areas with a high spatial and temporal resolution. Satellite images provide detailed multispectral information about the earth’s surface features, which proves invaluable for the characterization of vegetation, soil, water, and landforms at different scales. Vegetation cover, biomass, and soil properties were analyzed with remote sensing methods (NDVI, SDVI). It is emphasized that vegetation indices have little sensitivity at low leaf area which is common to all desert ecosystems.

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Mechanism for enhanced eolian dust flux recorded in North Pacific Ocean sediments since 4.0 Ma: Aridity or humidity at dust source areas in the Asian interior?

Geology ◽

10.1130/g46862.1 ◽

2019 ◽

Vol 48 (1) ◽

pp. 77-81 ◽

Cited By ~ 4

Author(s):

Qiang Zhang ◽

Qingsong Liu ◽

Andrew P. Roberts ◽

Juan C. Larrasoaña ◽

Xuefa Shi ◽

...

Keyword(s):

Pacific Ocean ◽

North Pacific ◽

Chemical Weathering ◽

Environmental Changes ◽

North Pacific Ocean ◽

Ocean Drilling Program ◽

Dust Source ◽

Source Areas ◽

Eolian Dust ◽

Global Cooling

Abstract Eolian material within pelagic North Pacific Ocean (NPO) sediments contains considerable information about paleoclimate evolution in Asian dust source areas. Eolian signals preserved in NPO sediments have been used as indices for enhanced Asian interior aridity. We here report a detailed eolian dust record, with chemical index of alteration (CIA) and Rb/Sr variations, for NPO sediments from Ocean Drilling Program Hole 885A over the past 4.0 m.y. CIA and Rb/Sr co-vary with the dust signal carried by combined eolian hematite and goethite concentrations. Changes in CIA around the intensification of Northern Hemisphere glaciation (iNHG) event at ca. 2.75 Ma indicate that dust production in source areas was associated mostly with physical and chemical weathering before and after the iNHG event, respectively. We here attribute the eolian flux increase into the NPO across the iNHG event mainly to increased availability of wind-erodible sediment in dust source areas derived from snow and glacial meltwater runoff, which resulted from glacial expansion and enhanced snowfall in the mountains surrounding the Tarim region in response to global cooling. Our results provide a deeper understanding of Asian interior environmental changes in response to global paleoclimate changes, where dust source areas became intermittently moister rather than more arid in response to global cooling.

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Linking transcription, RNA polymerase II elongation and alternative splicing

Biochemical Journal ◽

10.1042/bcj20200475 ◽

2020 ◽

Vol 477 (16) ◽

pp. 3091-3104 ◽

Cited By ~ 1

Author(s):

Luciana E. Giono ◽

Alberto R. Kornblihtt

Keyword(s):

Gene Expression ◽

Alternative Splicing ◽

Rna Polymerase Ii ◽

Environmental Changes ◽

Transcription Elongation ◽

Single Gene ◽

Regulation Of Gene Expression ◽

Regulation Of Transcription ◽

Stepping Stones ◽

Eukaryotic Transcription

Gene expression is an intricately regulated process that is at the basis of cell differentiation, the maintenance of cell identity and the cellular responses to environmental changes. Alternative splicing, the process by which multiple functionally distinct transcripts are generated from a single gene, is one of the main mechanisms that contribute to expand the coding capacity of genomes and help explain the level of complexity achieved by higher organisms. Eukaryotic transcription is subject to multiple layers of regulation both intrinsic — such as promoter structure — and dynamic, allowing the cell to respond to internal and external signals. Similarly, alternative splicing choices are affected by all of these aspects, mainly through the regulation of transcription elongation, making it a regulatory knob on a par with the regulation of gene expression levels. This review aims to recapitulate some of the history and stepping-stones that led to the paradigms held today about transcription and splicing regulation, with major focus on transcription elongation and its effect on alternative splicing.

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