48 research outputs found
Ocean acidification : a critical emerging problem for the ocean sciences
No full textAuthor Posting. © Oceanography Society, 2009. This article is posted here by permission of Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 22 no. 4 (2009): 16-25.Over a period of less than a decade, ocean acidification—the change in seawater
chemistry due to rising atmospheric carbon dioxide (CO2) levels and subsequent
impacts on marine life—has become one of the most critical and pressing issues
facing the ocean research community and marine resource managers alike. The objective
of this special issue of Oceanography is to provide an overview of the current
scientific understanding of ocean acidification as well as to indicate the substantial
gaps in our present knowledge. Papers in the special issue discuss the past, current,
and future trends in seawater chemistry; highlight potential vulnerabilities to marine
species, ecosystems, and marine resources to elevated CO2; and outline a roadmap
toward future research directions. In this introductory article, we present a brief
introduction on ocean acidification and some historical context for how it emerged so
quickly and recently as a key research topic.We thank the National Science
Foundation (NSF), National Oceanic and
Atmospheric Administration (NOAA),
and National Aeronautics and Space
Administration (NASA) for research
support on ocean acidification. We specifically acknowledge grants
supporting the OCB Project Office (NSF
OCE-0622984, NSF OCE-0927287,
and NASA NNX08AX01G). Richard A. Feely was
supported by the NOAA Climate
Program under the Office of Climate
Observations (Grant No. GC04-314
and the Global Carbon Cycle Program
(Grant No. GC05-288)
The impact of the North Atlantic Oscillation on the uptake and accumulation of anthropogenic CO2 by North Atlantic Ocean mode waters
No full textAuthor Posting. © American Geophysical Union, 2011. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Global Biogeochemical Cycles 25 (2011): GB3022, doi:10.1029/2010GB003892.The North Atlantic Ocean accounts for about 25% of the global oceanic anthropogenic carbon sink. This basin experiences significant interannual variability primarily driven by the North Atlantic Oscillation (NAO). A suite of biogeochemical model simulations is used to analyze the impact of interannual variability on the uptake and storage of contemporary and anthropogenic carbon (Canthro) in the North Atlantic Ocean. Greater winter mixing during positive NAO years results in increased mode water formation and subsequent increases in subtropical and subpolar Canthro inventories. Our analysis suggests that changes in mode water Canthro inventories are primarily due to changes in water mass volumes driven by variations in water mass transformation rates rather than local air-sea CO2 exchange. This suggests that a significant portion of anthropogenic carbon found in the ocean interior may be derived from surface waters advected into water formation regions rather than from local gas exchange. Therefore, changes in climate modes, such as the NAO, may alter the residence time of anthropogenic carbon in the ocean by altering the rate of water mass transformation. In addition, interannual variability in Canthro storage increases the difficulty of Canthro detection and attribution through hydrographic observations, which are limited by sparse sampling of subsurface waters in time and space.We would like to acknowledge funding
from the NOAA Climate Program under the Office of Climate Observations
and Global Carbon Cycle Program (NOAA‐NA07OAR4310098),
NSF (OCE‐0623034), NCAR, the WHOI Ocean Climate Institute, a
National Defense Science and Engineering Graduate Fellowship and an
Environmental Protection Agency STAR graduate fellowship. NCAR is
sponsored by the National Science Foundation
Ocean acidification : present conditions and future changes in a high-CO2 world
No full textAuthor Posting. © Oceanography Society, 2009. This article is posted here by permission of Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 22 no. 4 (2009): 36-47.The uptake of anthropogenic CO2 by the global ocean induces fundamental changes
in seawater chemistry that could have dramatic impacts on biological ecosystems in
the upper ocean. Estimates based on the Intergovernmental Panel on Climate Change
(IPCC) business-as-usual emission scenarios suggest that atmospheric CO2 levels
could approach 800 ppm near the end of the century. Corresponding biogeochemical
models for the ocean indicate that surface water pH will drop from a pre-industrial
value of about 8.2 to about 7.8 in the IPCC A2 scenario by the end of this century,
increasing the ocean’s acidity by about 150% relative to the beginning of the industrial
era. In contemporary ocean water, elevated CO2 will also cause substantial reductions
in surface water carbonate ion concentrations, in terms of either absolute changes
or fractional changes relative to pre-industrial levels. For most open-ocean surface
waters, aragonite undersaturation occurs when carbonate ion concentrations drop
below approximately 66 μmol kg-1. The model projections indicate that aragonite
undersaturation will start to occur by about 2020 in the Arctic Ocean and 2050 in
the Southern Ocean. By 2050, all of the Arctic will be undersaturated with respect to
aragonite, and by 2095, all of the Southern Ocean and parts of the North Pacific will
be undersaturated. For calcite, undersaturation occurs when carbonate ion concentration
drops below 42 μmol kg-1. By 2095, most of the Arctic and some parts of the
Bering and Chukchi seas will be undersaturated with respect to calcite. However, in
most of the other ocean basins, the surface waters will still be saturated with respect to
calcite, but at a level greatly reduced from the present.S. Cooley and S. Doney acknowledge
support from NSF ATM-0628582.
Richard A. Feely was supported by the
NOAA Climate Program under the
Office of Climate Observations (Grant
No. GC04-314 and the Global Carbon
Cycle Program (Grant No. GC05-288)
Comparison of CO2 dynamics and air-sea exchange in differing tropical reef environments
No full textAuthor Posting. © The Author(s), 2013. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Aquatic Geochemistry 19 (2013): 371-397, doi:10.1007/s10498-013-9214-7.Note from corresponding author: authors Feely and Shamberger were added after the initial submission, but before the final submission.An array of MAPCO2 buoys, CRIMP-2, Ala Wai, and Kilo Nalu, deployed in the coastal
waters of Hawaii have produced multiyear high temporal resolution CO2 records in three
different coral reef environments off the island of Oahu, Hawaii. This study, which includes data
from June 2008-December 2011, is part of an integrated effort to understand the factors that
influence the dynamics of CO2-carbonic acid system parameters in waters surrounding Pacific
high island coral reef ecosystems and subject to differing natural and anthropogenic stresses. The
MAPCO2 buoys are located on the Kaneohe Bay backreef, and fringing reef sites on the south
shore of O’ahu, Hawai’i. The buoys measure CO2 and O2 in seawater and in the atmosphere at
3-hour intervals, as well as other physical and biogeochemical parameters (CTD, chlorophyll-a,
turbidity). The buoy records, combined with data from synoptic spatial sampling, have allowed
us to examine the interplay between biological cycles of productivity/respiration and
calcification/dissolution and biogeochemical and physical forcings on hourly to inter-annual time
scales.
Air-sea CO2 gas exchange was also calculated to determine if the locations were sources
or sinks of CO2 over seasonal, annual, and interannual time periods. Net annualized fluxes for
CRIMP-2, Ala Wai, and Kilo Nalu over the entire study period were 1.15 mol C m-2 yr-1, 0.045
mol C m-2 yr-1, and -0.0056 mol C m-2 yr-1, respectively, where positive values indicate a source
or a CO2 flux from the water to the atmosphere, and negative values indicate a sink or flux of
CO2 from the atmosphere into the water. These values are of similar magnitude to previous
estimates in Kaneohe Bay as well as those reported from other tropical reef environments. Total
alkalinity (AT) was measured in conjunction with pCO2 and the carbonic acid system was
calculated to compare with other reef systems and open ocean values around Hawaii. These
findings emphasize the need for high-resolution data of multiple parameters when attempting to
characterize the carbonic-acid system in locations of highly variable physical, chemical, and
biological parameters (e.g. coastal systems, reefs).This
work was supported in part by a grant/cooperative agreement from the National Oceanic and
Atmospheric Administration, Project R/IR-3, which is sponsored by the University of Hawaii
Sea Grant College Program, SOEST, under Institutional Grant No. NA09OAR4170060 from
NOAA Office of Sea Grant, Department of Commerce.2014-11-0
Erratum: A CADM3 variant causes Charcot-Marie-Tooth disease with marked upper limb involvement (Brain (2021) 144:4 (1197-1213) DOI: 10.1093/brain/awab019)
No full textThe authors and publishers apologize for errors in the author affiliations and the References section. These have been corrected
Plastics in the automotive industry /
No full textA survey of the role of plastics materials in the motor industry. It discusses progress in the different sectors of automotive engineering, and the possible effect of economic and environmental pressures on the growth of the plastics contribution. Emphasis is given to materials selection and the author explains how a material can be 'right' or 'wrong' for a particular job - and what extraneous factors could change things."SAE order number: R-147"--Title page verso.Includes index.Online resource; title from PDF title page (ebrary, viewed February 07, 2014).A survey of the role of plastics materials in the motor industry. It discusses progress in the different sectors of automotive engineering, and the possible effect of economic and environmental pressures on the growth of the plastics contribution. Emphasis is given to materials selection and the author explains how a material can be 'right' or 'wrong' for a particular job - and what extraneous factors could change things.Front Cover; Plastics in the Automotive Industry; Copyright Page; Table of Contents; Preface; Acknowledgements; Chapter 1. Materials for cars; Plastics usage; History of automotive plastics; Why plastics?; Problems with plastics; Chapter 2. Understanding plastics; Classifying plastics; Composites; Processes; Designing with plastics; Chapter 3. Choosing plastics; The decisive properties; Characteristics of the polymer groups; Materials selection; Requirements for different application areas; Chapter 4. Interiors; General; Plastics surfaces; Plastics structures and panel applications.Structural and mechanical componentsChapter 5. Exteriors; Overview; Body panels and structures; The painting problem; Bumpers; Other exterior components; Bibliography; Books; Review papers and monographs; Conference papers; Technical and promotional literature; Chapter 6. Engine, power train and chassis; The engine compartment; The cooling system; Underbonnet stctures; Transmission; Engine 'hang-on' parts; Engine interiors; Composite engines; Suspension; Steering; Brakes; Fuel tanks; Chapter 7. EIectrics; Ignition; Battery boxes; Circuitry; lighting and instrumentation.Other electrical equipmentElectronics; Chapter 8. Recycling; Recycling: an unavoidable issue; The scrap problem; The alternatives for plastics; The energy aspect; Recycling composites; New recycling initiatives; Chapter 9. The future and automotive plastics; Design trends and legislation; Supplier involvement; Safety; Fuel economy and the energy equation; Environmental pollution; Plastics and future design; Appendix 1: Polymer abbreviations and trade names; Appendix 2: PC based polymer databases; Index.Elsevie
Efeito da temperatura em diferentes aspectos da fotossíntese de Lithothamnion superpositum (Corallinales, Rhodophyta
No full textTCC(graduação) - Universidade Federal de Santa Catarina. Centro de Ciências Biológicas. Biologia.As mudanças climáticas globais provocarão conseqüências físicas e químicas no ambiente marinho. Dentre elas, possíveis variações na temperatura promovem alterações fisiológicas alterando o comportamento respiratório e fotossintético e, assim as taxas de crescimento de organismos fitobênticos, especialmente. Dentre estes organismos, algas calcárias têm grande importância ecológica, com fornecimento de nicho e substrato para outras algas e invertebrados. Nesse grupo os efeitos de alterações da temperatura da água do mar são potencialmente ainda mais preocupantes, pois além de serem organismos chaves para o ambiente marinho, estão intimamente relacionadas ao ciclo do carbono. O presente trabalho verificou mudanças na resposta fotossintética de Lithothamnion superpositum (Corallinales, Rhodophyta) relacionadas à variação de temperatura. Assim, espécimes trazidos da Rebio do Arvoredo (22º C) foram incubados por 24h, a 15°C, 20°C, 25°C e 30°C. Por sete dias consecutivos as taxas de transferência de elétrons (ETR) e a fluorescência da Clorofila a do Fotossistema II foram aferidos com o fluorímetro DIVING-PAM. Também foram observados o balanço de oxigênio dissolvido e pH mantendo as plantas e controles no claro e escuro. Após esse tempo, foram extraídos os pigmentos (Aloficocianina, Ficocianina, Ficoeritrina e Clorofila). Os resultados evidenciam que as plantas mantidas a 20, 25 e 35°C, tiveram pouca diferença em relação à Pmáx, Ik e à β. Em relação à α não houve diferença significativa entre elas. Maiores concentrações de pigmentos foram encontradas nas plantas mantidas a 25°C. Pode-se sugerir, portanto, que as melhores temperaturas para as algas dessa espécie são as mais altas, encontradas nas regiões tropicais
Spatial variability and decadal trend of the oceanic CO2 in the western equatorial Pacific warm/fresh water
No full textData of the partial pressure of carbon dioxide in surface seawater (pCO2sw) collected in the western equatorial Pacific (144°E - 160°W, 5°S - 5°N) since the 1980's have been used to determine the spatial variability and decadal trends in pCO2sw. A total of 109 cruises since 1983, including 30 cruises since 1990 with total dissolved inorganic carbon (TCO2) measurements, are synthesized for this zone. The western equatorial Pacific warm/fresh surface water where T ≥ 29.0 ℃ and S ≤ 34.8 is nitrate-depleted and it is moderately supersaturated with CO2 (0 < ΔpCO2 (= pCO2sw - pCO2air) / μatm < 40). A slight CO2 undersaturation (-20 < ΔpCO2 / μatm < 0) was also observed on many cruises where thin, low density layers (σt < 21.4) capped barrier layers. The undersaturation may result from net biological uptake of CO2 due to nitrogen fixation. Excluding the data in such a extremely light waters, we determined changes in the linear growth rate of pCO2sw of +0.3 ± 1.3 μatm year^[-1] for 1985 - 1990, +2.2 ± 0.7 μatm year^[-1] for 1990 - 1999, and -0.2 ± 1.0 μatm year^[-1] for 1999 - 2004. The rate of increase was +1.5 ± 0.2 μatm year^[-1] for the entire period (1985 - 2004). The variation in the rate of increase of pCO2sw is fairly consistent with the change in the rate of increase of salinity-normalized TCO2 from +2.1 ± 0.4 μmol kg^[-1] year^[-1] during 1992 - 1999 to +0.4 ± 0.9 μmol kg^[-1] year^[-1] during 1999 - 2004. These changes are anti-correlated with the decadal variation in the geostrophic mass transport from subtropics of both hemispheres into the equatorial zone in the Pacific
Life-years-gained from population risk factor changes and modern cardiology treatments in Ireland
No full textBackground: Coronary heart disease (CHD) mortality rates in Ireland have halved since the mid-1980s, and adult life expectancy has also steadily improved. This study estimated the life-years-gained by CHD treatments and by changes in cardiovascular risk factor levels. Methods: A previously validated Irish IMPACT CHD mortality model was used to integrate large amounts of data on (i) patient numbers, (ii) treatment uptake, (iii) risk factor trends, (iv) effectiveness of cardiology treatments and risk factor reductions, and (v) median survival in patients with and without CHD, all stratified by age and sex. Results were tested in rigorous sensitivity analyses. Results: There were 3763 fewer CHD deaths than expected in 2000 compared with the base year, 1985. This resulted in ∼44 060 life-years-gained among people aged 25-84. Specific medical and surgical treatments given in 2000 for CHD patients together gained ∼14 505 life-years. Population changes in cholesterol and smoking levels accounted for some 32 705 life-years-gained, 66% from reductions in cholesterol alone. Adverse changes in obesity and diabetes resulted in a loss of ∼3670 life-years. Conclusions: Use of modern cardiology treatments in Ireland from 1985 to 2000 gained many thousands of life-years. However, twice as many life-years were generated by relatively modest reductions in major risk factors. Effective policies, such as the promotion of healthy diets, and weight reduction, together with the recent nationwide workplace smoking ban, will be essential to maintain and further enhance health gain. \ua9 The Author 2006. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved
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Locally interpolated alkalinity regression for global alkalinity estimation
No full textWe introduce methods and software for estimating total seawater alkalinity from salinity and any combination of up to four other parameters (potential temperature, apparent oxygen utilization, total dissolved nitrate, and total silicate). The methods return estimates anywhere in the global ocean with comparable accuracy to other published alkalinity estimation techniques. The software interpolates between a predetermined grid of coefficients for linear regressions onto arbitrary latitude, longitude, and depth coordinates, and thereby avoids the estimate discontinuities many similar methods return when transitioning from one regression constant set to another. The software can also return uncertainty estimates scaled by user-provided input parameter uncertainties. The methods have been optimized for the open ocean, for which we estimate globally averaged errors of 5.8–10.4 μmol kg⁻¹ depending on which combination of regression parameters is used. We expect these methods to be especially useful for better constraining the carbonate system from measurement platforms—such as biogeochemical Argo floats—that are only capable of measuring one carbonate system parameter (e.g., pH). It may also provide a useful way of simulating alkalinity for Earth system models that do not resolve the tracer prognostically.This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Wiley Periodicals, Inc. on behalf of the Association for the Sciences of Limnology and Oceanography. The published article can be found at: http://www.aslo.org/lomethods/index.html Datasets were acquired from the Carbon Dioxide Information and Analysis Center (CDIAC) webpage, from the HOT-DOGS data portal (http://hahana.soest.hawaii.edu/hot/hot-dogs/), and from the BATS data portal (http://bats.bios.edu/)
