Download or read book Impact of Aerosols Saharan Dust and Mixed on the East Mediterranean Oligotrophic Ecosystem Results from Experimental Studies written by Paraskevi Pitta and published by Frontiers Media SA. This book was released on 2017-11-16 with total page 209 pages. Available in PDF, EPUB and Kindle. Book excerpt: In oligotrophic environments, dust and nutrient inputs via atmospheric routes are considered important sources of macro-nutrients and micro-trace metals fuelling primary and secondary production. Yet, the impact of these dust inputs on the microbial populations is not fully investigated in the Eastern Mediterranean Sea (EMS). The response of oligotrophic systems to dust inputs, whether as positive or negative feedbacks to autotrophic and heterotrophic production and thus to biogeochemical cycling, is important to examine further. Experimental studies have explored nutrient additions in various combinations to determine the limiting resource to productivity or N2 fixation. Recent experimental studies have applied dust enrichments to bottle or mesocosm incubations of seawater from different oceanic regions. This research topic presents two Eastern Mediterranean dust addition mesocosm experiments using, for the first time, real aerosol additions, pure Saharan dust and mixed aerosols (a natural mixture of desert dust and polluted European particles), as well as other EMS aerosol experimental studies. The Topic includes manuscripts introducing results on: a) the impact of Saharan dust vs mixed aerosols on the autotrophic and heterotrophic surface microbial populations in the EMS, b) the impact of single vs multi-pulses of Saharan dust introduction into the pelagic environment of the EMS and c) other experimental studies of aerosol impacts on the EMS ecosystem.

Download or read book Asian Atmospheric Pollution written by Ramesh P. Singh and published by Elsevier. This book was released on 2021-08-31 with total page 582 pages. Available in PDF, EPUB and Kindle. Book excerpt: Asian Atmospheric Pollution: Sources, Characteristics and Impacts provides a concise yet comprehensive treatment of all aspects of pollution and air quality monitoring, across all of Asia. It focuses on key regions of the world and details a variety of sources, their transport mechanism, long term variability and impacts on climate at local and regional scales. It also discusses the feedback on pollutants, on different meteorological parameters like radiative forcing, fog formations, precipitation, cloud characteristics and more. Drawing upon the expertise of multiple well-known authors from different countries to underline some of these key issues, it includes sections dedicated to treatment of pollutant sources, studying of pollutants and trace gases using satellite/station based observations and models, transport mechanisms, seasonal and inter-annual variability and impact on climate, health and biosphere in general. Asian Atmospheric Pollution: Sources, Characteristics and Impacts is a useful resource for scientists and students to understand the sources and dynamics of atmospheric pollution as well as their transport from one continent to other continents, helping the atmospheric modelling community to model different scenarios of the pollution, gauge its short term and long term impacts across regional to global scales and better understand the ramifications of episodic events. Covers all of Asia in detail in terms of pollution Focuses not only on local pollution, but on long-term transport of these pollutants and their impacts on other regions as well as the globe Includes discussion of both particulate matter and greenhouse gases Serves as a single resource on Asian air pollution and Impacts from the most current research across the globe including the US, Asia, Africa and Europe

Download or read book The Impact of Saharan Dust on the North Atlantic Circulation written by Nidia Martínez Avellaneda and published by GRIN Verlag. This book was released on 2010-03-05 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: Doctoral Thesis / Dissertation from the year 2010 in the subject Geography / Earth Science - Meteorology, Aeronomy, Climatology, grade: Sehr Gut, University of Hamburg (Institute of Oceanography), language: English, abstract: The erosion of Saharan soil is the World's largest annual source of mineral dust aerosols, resulting in a deposition of more than 40% of the global atmospheric dust into the North Atlantic (NA). By changing the atmospheric opacity, mineral dust can alter the shortwave radiative forcing at the surface of the ocean, altering the ocean mixed layer heat budget and therefore affecting the sea surface temperature (SST). Moreover, changes of the total amount of energy received at the ocean surface have an impact on the ocean circulation. In this thesis we combine several satellite observations, in-situ radiation measurements, a 1D mixed layer model of the ocean, and various versions of a 3D general ocean circulation model, to study the impact of Saharan dust on the circulation of the NA. A buoyancy source generated by realistic dust-induced shortwave flux anomalies is imposed in the eastern NA and the differences between this simulation and an unperturbed one are investigated in terms of the ocean dynamical adjustment and changes in the Atlantic Meridional Overturning Circulation (AMOC). A joint analysis of aerosol optical depth retrievals from the MODIS sensor and SST from the TMI sensor for the period 2000-2006 shows a decrease in SST of 0.2° to 0.4°C simultaneously with, or shortly after, strong dust outbreaks, which is consistent with an independent estimate of SST decrease simulated by a local 1D mixed layer model. A comparison between observed TMI SST fields and simulated SSTs with an eddy-permitting model of the NA suggests a local cooling of about 0.5°C on sub-seasonal to interannual time-scales. Results of the 3D simulations show that an advection of the ocean properties ocurs in response to the buoyancy source in the eastern subtropical NA. The eddies and baroclinic instabilities present in the ocean advect the signal towards the west and back towards the east. Once they have reached the African coast, they trigger westward propagating Rossby waves. The time-mean differences of AMOC between the perturbed and unperturbed simulations show an increased meridional transport at 38°N and 43°N of 0.55 and 0.45 Sv, respectively, and a decreased AMOC at 40°N and 45°N of 0.2 Sv. We conclude that the effect of Saharan dust should be incorporated in ocean numerical simulations, specially under the frame of climate change studies when a changing dust load of the atmosphere in response to a changing climate could be possible.

Download or read book Practical Guidelines for the Analysis of Seawater written by Oliver Wurl and published by CRC Press. This book was released on 2009-06-09 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: As we discover more about the role of the ocean in global changes and identify the effects of global change on the ocean, understanding its chemical composition and processes becomes increasingly paramount. However, understanding these processes requires a wide range of measurements in the vast ocean, from the sea surface to deep-ocean trenches, fr

Download or read book Handbook of Methods in Aquatic Microbial Ecology written by Paul F. Kemp and published by Routledge. This book was released on 2018-05-02 with total page 823 pages. Available in PDF, EPUB and Kindle. Book excerpt: Handbook of Methods in Aquatic Microbial Ecology is the first comprehensive compilation of 85 fundamental methods in modern aquatic microbial ecology. Each method is presented in a detailed, step-by-step format that allows readers to adopt new methods with little difficulty. The methods represent the state of the art, and many have become standard procedures in microbial research and environmental assessment. The book also presents practical advice on how to apply the methods. It will be an indispensable reference for marine and freshwater research laboratories, environmental assessment laboratories, and industrial research labs concerned with microbial measurements in water.

Download or read book The Impact of Desert Dust Across the Mediterranean written by Stefano Guerzoni and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt: The atmosphere is an important pathway for the transport of continentally-derived material to the oceans. In this respect the Mediterranean Sea is of special importance because its atmosphere receives inputs of anthropogenic aerosols from the north and desert- derived Saharan dusts from the south. The dusts, much of which is transported in the form of seasonal `pulses', have important effects on climate, marine chemistry and sedimentation in the Mediterranean Sea. This volume brings together reviews and specific-topic papers on the following aspects of Saharan dust transport to the Mediterranean Sea: (i) the modelling of Saharan dust transport, (ii) the chemistry and mineralogy of the dusts and their effect on precipitation, (iii) the contribution of the dusts to marine sedimentation, (iv) the aerobiology of the dusts, and (v) climatic implications of Saharan dust transport. The volume is aimed at students and researchers with an interest in the climate, biogeochemistry and geology of the Mediterranean Sea.

Download or read book Ocean Atmosphere Interactions of Gases and Particles written by Peter S. Liss and published by Springer. This book was released on 2013-12-18 with total page 315 pages. Available in PDF, EPUB and Kindle. Book excerpt: The oceans and atmosphere interact through various processes, including the transfer of momentum, heat, gases and particles. In this book leading international experts come together to provide a state-of-the-art account of these exchanges and their role in the Earth-system, with particular focus on gases and particles. Chapters in the book cover: i) the ocean-atmosphere exchange of short-lived trace gases; ii) mechanisms and models of interfacial exchange (including transfer velocity parameterisations); iii) ocean-atmosphere exchange of the greenhouse gases carbon dioxide, methane and nitrous oxide; iv) ocean atmosphere exchange of particles and v) current and future data collection and synthesis efforts. The scope of the book extends to the biogeochemical responses to emitted / deposited material and interactions and feedbacks in the wider Earth-system context. This work constitutes a highly detailed synthesis and reference; of interest to higher-level university students (Masters, PhD) and researchers in ocean-atmosphere interactions and related fields (Earth-system science, marine / atmospheric biogeochemistry / climate). Production of this book was supported and funded by the EU COST Action 735 and coordinated by the International SOLAS (Surface Ocean- Lower Atmosphere Study) project office.

Download or read book Impact of Saharan Dust Aerosols on Radiation and Clouds Over the Tropical East Atlantic Ocean written by Abdulla Al Mamun and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aerosols affect the atmospheric processes by interacting with shortwave (SW) and longwave (LW) radiations and also by modifying the cloud microphysics (direct and indirect effects respectively). This study investigates the direct and indirect effects of Saharan dust aerosols, and the subsequent perturbations of the radiation budget and tropical convection by using the Weather Research and Forecasting model coupled with Chemistry module (WRF-Chem). Simulations are conducted for July 1-31, 2010 over two-way nested domains in the tropical East Atlantic Ocean. Results show that the interactions of dust particles with the SW and LW radiations enhance the heating rates in the atmosphere and primarily affect the upwelling SW radiation at the top of the atmosphere, and downwelling SW and LW radiations at the surface. Dust induced lower level heating increases the stability of the lower troposphere. As a result, convection is inhibited below the dust layers and enhanced in the levels inside and above the dust layers. Dust particles acting as the cloud condensation nuclei (CCN) lead to enhanced condensation and produce numerous cloud droplets with reduced droplet sizes. Consequently, slower collision coalescence among the cloud droplets affects the droplet autoconversion rate and reduces the rain production. However, there is no evidence of the suppression of accumulated precipitation at the surface that would otherwise increase the cloud lifetime. The net radiative forcing of dust is positive inside the atmosphere, and negative at the surface, and top of the atmosphere. Due to the overall positive radiative feedback from the cloud, the magnitudes of the forcing at surface and top of the atmosphere become weaker in the presence of clouds.

Download or read book The Impact of Saharan Dust on Atlantic Convective Systems written by Jianyu Liang and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tropical weather systems such as the African Easterly Waves (AEWs), the African Easterly Jet (AEJ), and tropical cyclones usually interact with the Saharan Air Layer (SAL) and mineral dust aerosols embedded in the SAL. Previous studies have debates about the strength and even the direction of the impact from the dust and SAL on the development of the tropical systems. In this study, the sole impact from the dust on a hurricane is quantified using carefully designed numerical experiments. Hurricane Earl (2010) was originated from an AEW disturbance over Africa. It was influenced by the dusty SAL especially in its early development stage. We conduct numerical experiments using the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) to simulate Hurricane Earl (2010) starting from a weak disturbance. Experiments with 36-km resolution show that without moist convection, dust slightly weakens the low-pressure system in North Africa by cooling the atmosphere. This scenario mainly results from a reduction of the boundary layer heating during the daytime and from the enhancement of the outgoing longwave radiative cooling during the nighttime. The zonal mean of the AEJ is intensified slightly (less than 1m/s) in its southern part and weakened in its northern part when dust is included in the model. Adding dust weakens the AEWs at 850 hPa and 600 hPa levels and the tropical cyclone. High-resolution (4-km) cloud-resolving model experiments show that dust deepens the system slightly but does not affect the track. In the tropical low stage, dust increases the low-level cloud at 1-2 km height. It reduces rainfall in the outer edge of SAL region between 250 km to 350 km radii while it increases rainfall in the inner edge at around 200 km. The associated latent heat release shifts the updraft radially inward. The dynamical consequence is the acceleration of the tangential wind and the mid-level circulation. In the tropical depression stage, adding dust increases the number of cloud droplets in most of the regions and enhances the convection around the center, which generates more ice, snow, and rain. Overall, the impact of dust aerosols on Earl is small, the center minimum sea-level pressures only differ by less than 1 hPa at the end of the simulation. This suggests that pure meteorological model may be sufficiently accurate to forecast hurricanes if the dynamical and thermodynamical features of the SAL are properly described. In order to predict aerosols, one can use a simple chemistry model such as GOCART which only has aerosol direct effects. Using the Ensemble Kalman Filter (EnKF) to assimilate conventional observations and MODIS aerosol optical depth (AOD) data, both forecasts of the track of the storm and the aerosol can be improved.

Download or read book The Mediterranean Sea in the Era of Global Change 1 written by Christophe Migon and published by John Wiley & Sons. This book was released on 2020-02-19 with total page 191 pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to its particular characteristics, the Mediterranean Sea is often viewed as a microcosm of the World Ocean. Its proportionally-reduced dimensions and peculiar hydrological circulation render it susceptible to environmental and climatic constraints, which are rapidly evolving. The Mediterranean is therefore an ideal site to examine, in order to better understand a number of key oceanographic phenomena. This is especially true of the Ligurian Sea where, due to its geology, oceanic conditions are found close to the coast. As such, 30 years ago, an offshore time-series site provided a fresh impetus to a long history of marine biology research, which has generated a very important body of data and knowledge. This is the first volume, in a two-volume series, that summarizes this research. Across these two books, the reader will find 13 chapters that examine the geology, physics, chemistry and biology of the Ligurian Sea ? always with the goal of providing key elements of oceanography in a changing world.

Download or read book The Mediterranean region under climate change written by Collectif and published by IRD Éditions. This book was released on 2018-11-19 with total page 736 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book has been published by Allenvi (French National Alliance for Environmental Research) to coincide with the 22nd Conference of Parties to the United Nations Framework Convention on Climate Change (COP22) in Marrakesh. It is the outcome of work by academic researchers on both sides of the Mediterranean and provides a remarkable scientific review of the mechanisms of climate change and its impacts on the environment, the economy, health and Mediterranean societies. It will also be valuable in developing responses that draw on “scientific evidence” to address the issues of adaptation, resource conservation, solutions and risk prevention. Reflecting the full complexity of the Mediterranean environment, the book is a major scientific contribution to the climate issue, where various scientific considerations converge to break down the boundaries between disciplines.

Download or read book Ocean Atmosphere Interactions written by Y. Toba and published by The Rosen Publishing Group. This book was released on 2003-08-31 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents an up-to-date analysis of ocean-atmosphere interaction. Well known experts examine diverse subjects such as ocean surface waves, air-sea exchange processes, ocean surface mixed layer, water-mass formation, as well as general circulation of the oceans, El Nino and Southern Oscillation (ENSO), and the deep-ocean circulation. Other areas described are basic dynamics, data analysis techniques, numerical modelling, and remote sensing. This book is primarily aimed at graduate and senior undergraduate courses in the area of ocean-atmosphere research.

Download or read book Processes in Microbial Ecology written by David L. Kirchman and published by OUP Oxford. This book was released on 2012-02-02 with total page 597 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microbial ecology is the study of interactions among microbes in natural environments and their roles in biogeochemical cycles, food web dynamics, and the evolution of life. Microbes are the most numerous organisms in the biosphere and mediate many critical reactions in elemental cycles and biogeochemical reactions. Because microbes are essential players in the carbon cycle and related processes, microbial ecology is a vital science for understanding the role of the biosphere in global warming and the response of natural ecosystems to climate change. This novel textbook discusses the major processes carried out by viruses, bacteria, fungi, protozoa and other protists - the microbes - in freshwater, marine, and terrestrial ecosystems. It focuses on biogeochemical processes, starting with primary production and the initial fixation of carbon into cellular biomass, before exploring how that carbon is degraded in both oxygen-rich (oxic) and oxygen-deficient (anoxic) environments. These biogeochemical processes are affected by ecological interactions, including competition for limiting nutrients, viral lysis, and predation by various protists in soils and aquatic habitats. The book neatly connects processes occurring at the micron scale to events happening at the global scale, including the carbon cycle and its connection to climate change issues. A final chapter is devoted to symbiosis and other relationships between microbes and larger organisms. Microbes have huge impacts not only on biogeochemical cycles, but also on the ecology and evolution of more complex forms of life, including Homo sapiens..

Download or read book The Ocean and Cryosphere in a Changing Climate written by Intergovernmental Panel on Climate Change (IPCC) and published by Cambridge University Press. This book was released on 2022-05-19 with total page 1807 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Intergovernmental Panel on Climate Change (IPCC) is the leading international body for assessing the science related to climate change. It provides policymakers with regular assessments of the scientific basis of human-induced climate change, its impacts and future risks, and options for adaptation and mitigation. This IPCC Special Report on the Ocean and Cryosphere in a Changing Climate is the most comprehensive and up-to-date assessment of the observed and projected changes to the ocean and cryosphere and their associated impacts and risks, with a focus on resilience, risk management response options, and adaptation measures, considering both their potential and limitations. It brings together knowledge on physical and biogeochemical changes, the interplay with ecosystem changes, and the implications for human communities. It serves policymakers, decision makers, stakeholders, and all interested parties with unbiased, up-to-date, policy-relevant information. This title is also available as Open Access on Cambridge Core.

Download or read book Nitrogen Loading in Coastal Water Bodies written by Richard A. Valigura and published by American Geophysical Union. This book was released on 2001-01-09 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: Published by the American Geophysical Union as part of the Coastal and Estuarine Studies, Volume 57. Every time it rains, biologically active nitrogen compounds are transferred from the air to whatever surface lies underneath; what a farmer once called "the poor man's fertilizer." In fact, nitrogen containing compounds are transferred between surface and atmosphere even when it is not raining. That this atmospheric nitrogen deposition impacts on the environment is a scientifically accepted fact, established during the acid rain debates led by the National Acid Precipitation Assessment Program. The extent to which this deposition contributes to the decline of coastal waters around the United States due to over fertilization, however, is still under debate. In response to and as a continuation of this debate is the current work before you: the first attempt to consistently and comprehensively estimate the relative contribution of atmospherically delivered nitrogen to the total amount of nitrogen entering coastal estuaries around the United States.

Download or read book Real time Coastal Observing Systems for Marine Ecosystem Dynamics and Harmful Algal Blooms written by Babin, Marcel and published by UNESCO. This book was released on 2008-06-05 with total page 880 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proliferation of harmful phytoplankton in marine ecosystems can cause massive fish kills, contaminate seafood with toxins, impact local and regional economies and dramatically affect ecological balance. Real-time observations are essential for effective short-term operational forecasting, but observation and modelling systems are still being developed. This volume provides guidance for developing real-time and near real-time sensing systems for observing and predicting plankton dynamics, including harmful algal blooms, in coastal waters. The underlying theory is explained and current trends in research and monitoring are discussed.Topics covered include: coastal ecosystems and dynamics of harmful algal blooms; theory and practical applications of in situ and remotely sensed optical detection of microalgal distributions and composition; theory and practical applications of in situ biological and chemical sensors for targeted species and toxin detection; integrated observing systems and platforms for detection; diagnostic and predictive modelling of ecosystems and harmful algal blooms, including data assimilation techniques; observational needs for the public and government; and future directions for research and operations.

Download or read book Mineral Dust written by Peter Knippertz and published by Springer. This book was released on 2014-09-01 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents state-of-the-art research about mineral dust, including results from field campaigns, satellite observations, laboratory studies, computer modelling and theoretical studies. Dust research is a new, dynamic and fast-growing area of science and due to its multiple roles in the Earth system, dust has become a fascinating topic for many scientific disciplines. Aspects of dust research covered in this book reach from timescales of minutes (as with dust devils, cloud processes and radiation) to millennia (as with loess formation and oceanic sediments), making dust both a player and recorder of environmental change. The book is structured in four main parts that explore characteristics of dust, the global dust cycle, impacts of dust on the Earth system, and dust as a climate indicator. The chapters in these parts provide a comprehensive, detailed overview of this highly interdisciplinary subject. The contributions presented here cover dust from source to sink and describe all the processes dust particles undergo while travelling through the atmosphere. Chapters explore how dust is lifted and transported, how it affects radiation, clouds, regional circulations, precipitation and chemical processes in the atmosphere and how it deteriorates air quality. The book explores how dust is removed from the atmosphere by gravitational settling, turbulence or precipitation, how iron contained in dust fertilizes terrestrial and marine ecosystems, and about the role that dust plays in human health. We learn how dust is observed, simulated using computer models and forecast. The book also details the role of dust deposits for climate reconstructions. Scientific observations and results are presented, along with numerous illustrations. This work has an interdisciplinary appeal and will engage scholars in geology, geography, chemistry, meteorology and physics, amongst others with an interest in the Earth system and environmental change. body>