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Benthic Community Response to Iceberg Scouring at an Intensely Disturbed Shallow Water Site at Adelaide Island, Antarctica
Vol. 355: 85–94, 2008 MARINE ECOLOGY PROGRESS SERIES Published February 26 doi: 10.3354/meps07311 Mar Ecol Prog Ser Benthic community response to iceberg scouring at an intensely disturbed shallow water site at Adelaide Island, Antarctica Dan A. Smale*, David K. A. Barnes, Keiron P. P. Fraser, Lloyd S. Peck British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge CB3 OET, UK ABSTRACT: Disturbance is a key structuring force influencing shallow water communities at all latitudes. Polar nearshore communities are intensely disturbed by ice, yet little is known about benthic recovery following iceberg groundings. Understanding patterns of recovery following ice scour may be particularly important in the West Antarctic Peninsula region, one of the most rapidly changing marine systems on Earth. Here we present the first observations from within the Antarc- tic Circle of community recovery following iceberg scouring. Three grounded icebergs were marked at a highly disturbed site at Adelaide Island (~67° S) and the resultant scours were sampled at <1, 3, 6, 12, 18 and 30 to 32 mo following formation. Each iceberg impact was catastrophic in that it resulted in a 92 to 96% decrease in abundance compared with reference zones, but all post- scoured communities increased in similarity towards ‘undisturbed’ assemblages over time. Taxa recovered at differing rates, probably due to varying mechanisms of return to scoured areas. By the end of the study, we found no differences in abundance between scoured and reference samples for 6 out of 9 major taxonomic groups. Five pioneer species had consistently elevated abundances in scours compared with reference zones. -
River Ice Management in North America
RIVER ICE MANAGEMENT IN NORTH AMERICA REPORT 2015:202 HYDRO POWER River ice management in North America MARCEL PAUL RAYMOND ENERGIE SYLVAIN ROBERT ISBN 978-91-7673-202-1 | © 2015 ENERGIFORSK Energiforsk AB | Phone: 08-677 25 30 | E-mail: [email protected] | www.energiforsk.se RIVER ICE MANAGEMENT IN NORTH AMERICA Foreword This report describes the most used ice control practices applied to hydroelectric generation in North America, with a special emphasis on practical considerations. The subjects covered include the control of ice cover formation and decay, ice jamming, frazil ice at the water intakes, and their impact on the optimization of power generation and on the riparians. This report was prepared by Marcel Paul Raymond Energie for the benefit of HUVA - Energiforsk’s working group for hydrological development. HUVA incorporates R&D- projects, surveys, education, seminars and standardization. The following are delegates in the HUVA-group: Peter Calla, Vattenregleringsföretagen (ordf.) Björn Norell, Vattenregleringsföretagen Stefan Busse, E.ON Vattenkraft Johan E. Andersson, Fortum Emma Wikner, Statkraft Knut Sand, Statkraft Susanne Nyström, Vattenfall Mikael Sundby, Vattenfall Lars Pettersson, Skellefteälvens vattenregleringsföretag Cristian Andersson, Energiforsk E.ON Vattenkraft Sverige AB, Fortum Generation AB, Holmen Energi AB, Jämtkraft AB, Karlstads Energi AB, Skellefteå Kraft AB, Sollefteåforsens AB, Statkraft Sverige AB, Umeå Energi AB and Vattenfall Vattenkraft AB partivipates in HUVA. Stockholm, November 2015 Cristian -
Sea Ice Growth and Decay a Remote Sensing Perspective Sea Ice Growth & Decay
Sea Ice Growth And Decay A Remote Sensing Perspective Sea Ice Growth & Decay Add snow here Loss of Sea Ice in the Arctic Donald K. Perovich and Jacqueline A. Richter-Menge Annual Review of Marine Science 2009 1:1, 417-441 Sea Ice Remote Sensing Method Physical Property Sensor Type Geophysical Variable Passive Microwave Surface Emissivity Radiometer Sea Ice Concentration ~ 1 – 100 GHz Sea Ice Classification Sea Ice Motion Thin Sea Ice Thickness (Snow Depth) Active Microwave Backscatter SAR Sea Ice Classification Sea Ice Motion Very Thin Sea Ice Thickness Scatterometer Sea Ice Type Altimeter Sea Ice Thickness (Snow Depth) Optical Spectral Albedo Spectrometer Floe Sizes Distribution Melt Pond Coverage Melt Pond Depth Infrared Surface Emissivity Radiometer Sea Ice Surface Temperature Thin Sea Ice Thickness Laser Backscatter Altimeter Sea Ice Thickness What are the main processes of sea ice growth & decay? How do they affect sea ice remote sensing? How to observe these processes independently? Formation Redistribution Snow Surface Melt & Growth Processes Annual Cycle of Sea Ice Sea Ice Extent Area covered at least with 15% sea ice (according to passive microwave data) Long-Term Sea Ice Trends Sea Ice Extent Sea Ice Thickness Passive Microwave Time Series Submarines, Moorings, Airborne Surveys Arctic Antarctic No comparable sea ice thickness data record Sea Ice Age & Type Sea Ice Age Sea Ice Type Model with observed ice drift & concentration Passive & Active Microwave Formation Redistribution Snow Surface Melt & Growth Processes Early Sea Ice -
Frazil-Ice Nucleation by Mass-Exchange Processes at the Air- Water Interface
J ournal oIG/acio logy, V o !. 19, No. 8 1, 197 7 FRAZIL-ICE NUCLEATION BY MASS-EXCHANGE PROCESSES AT THE AIR- WATER INTERFACE By T. E. O ST E RKAMP':' (Geophysical Institute, University of Alaska, Fairbanks, A laska 99701, U .S.A. ) AosTRACT. T he physical requirem ents for proposed frazil-ice nucleati on theori es are reviewed in the light of recent observations on frazil-ice forma tion. It is concluded that sponta neous heterogeneous nucleation in a thin supercooled surface la yer of wa ter is not a via ble mechanism for frazil-ice nucleation. E fforts to observe crys ta l multiplicati on b y b order ice have n o t been successful. The mass-excha nge m echanism proposed by O sterka mp and others ( 1974) has been gen era li zed to include splashing, wind spray, bubble bursting, evapo ra tion, a nd ma teria l tha t originates a t a dista nce from the strea m (e. g. snow, frost, ice pa rticles, cold orga nic m a teria l, a nd cold soil pa rticles). I t is shown that these mass-exchange processes ca n account for frazil-ice nucleation under a wide ra nge of phys ical a nd meteorological conditions. It is suggested that secondary nuclea tion may be responsible for large frazil-ice concentra tions in streams and rivers. R EsuME. JVllcieatioll de la glace dll ''.fra zil'' par des processus d'echallges de masses a I'illlerface air ell eall. O n a rev u les conditions physiques requises pa r les theories p our la nucleation d e la glace du " frazil " a la lumicre de recentes observations sur cette forma ti on. -
The Effects of Rotation and Ice Shelf Topography on Frazil-Laden Ice Shelf Water Plumes
The effects of rotation and ice shelf topography on frazil-laden ice shelf water plumes Article Published Version Holland, P. R. and Feltham, D. L. (2006) The effects of rotation and ice shelf topography on frazil-laden ice shelf water plumes. Journal of Physical Oceanography, 36 (12). pp. 2312-2327. ISSN 0022-3670 doi: https://doi.org/10.1175/JPO2970.1 Available at http://centaur.reading.ac.uk/34907/ It is advisable to refer to the publisher’s version if you intend to cite from the work. See Guidance on citing . Published version at: http://dx.doi.org/10.1175/JPO2970.1 To link to this article DOI: http://dx.doi.org/10.1175/JPO2970.1 Publisher: American Meteorological Society All outputs in CentAUR are protected by Intellectual Property Rights law, including copyright law. Copyright and IPR is retained by the creators or other copyright holders. Terms and conditions for use of this material are defined in the End User Agreement . www.reading.ac.uk/centaur CentAUR Central Archive at the University of Reading Reading’s research outputs online 2312 JOURNAL OF PHYSICAL OCEANOGRAPHY VOLUME 36 The Effects of Rotation and Ice Shelf Topography on Frazil-Laden Ice Shelf Water Plumes ϩ PAUL R. HOLLAND* AND DANIEL L. FELTHAM Centre for Polar Observation and Modelling, University College London, London, United Kingdom (Manuscript received 24 June 2005, in final form 20 April 2006) ABSTRACT A model of the dynamics and thermodynamics of a plume of meltwater at the base of an ice shelf is presented. Such ice shelf water plumes may become supercooled and deposit marine ice if they rise (because of the pressure decrease in the in situ freezing temperature), so the model incorporates both melting and freezing at the ice shelf base and a multiple-size-class model of frazil ice dynamics and deposition. -
The Effects of Ice on Stream Flow
LIBRARY COPY DEPARTMENT OF THE INTERIOR UNITED STATES GEOLOGICAL SURVEY GEORGE OTI8 SMITH, DIKECTOK WATER-SUPPLY PAPER 337 THE EFFECTS OF ICE ON STREAM FLOW BY WILLIAM GLENN HOYT WASHINGTON GOVERNMENT PRINTING OFFICE 1913 CONTENTS. Page. Introduction____________________________________ 7 Factors that modify winter run-off_______________________ 9 Classification_________________________________ 9 Climatic factors_______________________________ 9 Precipitation and temperature____________________ 9 Barometric pressure__________________________ 17 Chinook winds________________________________ 18 Geologic factors________________________________ 19 Topographic factors______________________________ 20 Natural storage_____________________________ 20 Location, size, and trend of drainage basins____________ 22 Character of streams_________________________ 22 Vegetational factors_____________________________. 23 Artificial control _________________________________ 23 Formation of ice______________________________^____ 24 General conditions ________________________________ 24 Surface ice __ __ __ ___________________ 24 Method of formation____________________________. 24 Length and severity of cold period__________________ 25 Temperature of affluents________________________'__ 26 Velocity of water and. character of bed_______________ 27 Fluctuations in stage__________________________ 27 Frazil______________________________________ 28 Anchor ice_____________________ __________ 29 Effect of ice on relation of stage to discharge_________ ______ 30 The -
Laboratory Study of Frazil Ice Accumulation
Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | The Cryosphere Discuss., 5, 1835–1886, 2011 The Cryosphere www.the-cryosphere-discuss.net/5/1835/2011/ Discussions TCD doi:10.5194/tcd-5-1835-2011 5, 1835–1886, 2011 © Author(s) 2011. CC Attribution 3.0 License. Laboratory study of This discussion paper is/has been under review for the journal The Cryosphere (TC). frazil ice Please refer to the corresponding final paper in TC if available. accumulation S. De la Rosa and S. Maus Laboratory study of frazil ice Title Page accumulation under wave conditions Abstract Introduction S. De la Rosa1,2 and S. Maus1 Conclusions References 1Geophysical Institute, University of Bergen, Allegaten´ 70, 5007, Bergen, Norway Tables Figures 2Nansen Environmental and Remote Sensing Center/Mohn-Sverdrup Center, Thormøhlensgate 47, 5006, Bergen, Norway J I Received: 27 May 2011 – Accepted: 13 June 2011 – Published: 8 July 2011 J I Correspondence to: S. De la Rosa ([email protected]) Back Close Published by Copernicus Publications on behalf of the European Geosciences Union. Full Screen / Esc Printer-friendly Version Interactive Discussion 1835 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Abstract TCD Ice growth in turbulent seawater is often accompanied by the accumulation of frazil ice crystals at its surface. The thickness and volume fraction of this ice layer play an 5, 1835–1886, 2011 important role in shaping the gradual transition from a loose to a solid ice cover, how- 5 ever, observations are very sparse. Here we analyse an extensive set of observations Laboratory study of of frazil ice, grown in two parallel tanks with controlled wave conditions and thermal frazil ice forcing, focusing on the first one to two days of grease ice accumulation. -
Snowterm: a Thesaurus on Snow and Ice Hierarchical and Alphabetical Listings
Quaderno tematico SNOWTERM: A THESAURUS ON SNOW AND ICE HIERARCHICAL AND ALPHABETICAL LISTINGS Paolo Plini , Rosamaria Salvatori , Mauro Valt , Valentina De Santis, Sabina Di Franco Version: November 2008 Quaderno tematico EKOLab n° 2 SnowTerm: a thesaurus on snow and ice hierarchical and alphabetical listings Version: November 2008 Paolo Plini1, Rosamaria Salvatori2, Mauro Valt3, Valentina De Santis1, Sabina Di Franco1 Abstract SnowTerm is the result of an ongoing work on a structured reference multilingual scientific and technical vocabulary covering the terminology of a specific knowledge domain like the polar and the mountain environment. The terminological system contains around 3.700 terms and it is arranged according to the EARTh thesaurus semantic model. It is foreseen an updated and expanded version of this system. 1. Introduction The use, management and diffusion of information is changing very quickly in the environmental domain, due also to the increased use of Internet, which has resulted in people having at their disposition a large sphere of information and has subsequently increased the need for multilingualism. To exploit the interchange of data, it is necessary to overcome problems of interoperability that exist at both the semantic and technological level and by improving our understanding of the semantics of the data. This can be achieved only by using a controlled and shared language. After a research on the internet, several glossaries related to polar and mountain environment were found, written mainly in English. Typically these glossaries -with a few exceptions- are not structured and are presented as flat lists containing one or more definitions. The occurrence of multiple definitions might contribute to increase the semantic ambiguity, leaving up to the user the decision about the preferred meaning of a term. -
Frazil Ice: a Review of Its Properties, with a Selected Bibliography Williams, G
NRC Publications Archive Archives des publications du CNRC Frazil ice: a review of its properties, with a selected bibliography Williams, G. P. This publication could be one of several versions: author’s original, accepted manuscript or the publisher’s version. / La version de cette publication peut être l’une des suivantes : la version prépublication de l’auteur, la version acceptée du manuscrit ou la version de l’éditeur. Publisher’s version / Version de l'éditeur: Engineering Journal, 42, 11, pp. 55-60, 1959-12-01 NRC Publications Record / Notice d'Archives des publications de CNRC: https://nrc-publications.canada.ca/eng/view/object/?id=f683a087-d82c-4542-81e8-398c95993824 https://publications-cnrc.canada.ca/fra/voir/objet/?id=f683a087-d82c-4542-81e8-398c95993824 Access and use of this website and the material on it are subject to the Terms and Conditions set forth at https://nrc-publications.canada.ca/eng/copyright READ THESE TERMS AND CONDITIONS CAREFULLY BEFORE USING THIS WEBSITE. L’accès à ce site Web et l’utilisation de son contenu sont assujettis aux conditions présentées dans le site https://publications-cnrc.canada.ca/fra/droits LISEZ CES CONDITIONS ATTENTIVEMENT AVANT D’UTILISER CE SITE WEB. Questions? Contact the NRC Publications Archive team at [email protected]. If you wish to email the authors directly, please see the first page of the publication for their contact information. Vous avez des questions? Nous pouvons vous aider. Pour communiquer directement avec un auteur, consultez la première page de la revue dans laquelle son article a été publié afin de trouver ses coordonnées. -
Open PDF File, 757.01 KB, for 302 Surface Ice Rescue.Pdf
DEPARTMENT OF FIRE SERVICES Massachusetts Firefighting Academy SURFACE ICE RESCUE STUDENT GUIDE Ver. 51502 GENERAL DESCRIPTION Ice rescue presents unique problems for the firefighter that require specialized technical skills to solve them. Too many times in the past, firefighters themselves have fallen victim to the hazards of ice rescue. In most cases, this can be attributed to deficiencies in three areas: proper training, equipment, and knowledge. This course is designed to train the firefighter in the most current techniques in Ice Rescue. The primary objectives of this program are to execute the following: • Train the firefighter how to recognize ice characteristics, its strengths, and weaknesses • To provide the firefighter with the knowledge to understand how hypothermia can affect both the victim as well as the rescuer • Train the firefighter in proper techniques in planning and executing the appropriate rescue procedures and equipment using REACH, THROW, AND GO methods • To provide the firefighter with a greater sense of competency in dealing with Ice rescues REFERENCES Ice Rescue Manual, Pennsylvania Fish Commission Ice Rescue Manual, Ohio Department of Natural Resources, Division of Watercraft Fire Service Rescue Practices, IFSTA, Fifth Edition Cold Water Rescue, Connecticut Firefighting Academy METHOD OF INSTRUCTION Lecture, Audio/Video, and Practical Exercises Surface Ice Rescue Student Guide Page 1 SEGMENTS OF INSTRUCTION INTRODUCTION Why Ice Rescue? SECTION I Recognizing Ice Characteristics • Ice development • Ice classification -
Frazil Ice Formation in the Polar Oceans
Frazil Ice Formation in the Polar Oceans Nikhil Vibhakar Radia Department of Earth Sciences, UCL A thesis submitted for the degree of Doctor of Philosophy Supervisor: D. L. Feltham August, 2013 1 I, Nikhil Vibhakar Radia, confirm that the work presented in this thesis is my own. Where information has been derived from other sources, I confirm that this has been indicated in the thesis. SIGNED 2 Abstract Areas of open ocean within the sea ice cover, known as leads and polynyas, expose ocean water directly to the cold atmosphere. In winter, these are regions of high sea ice production, and they play an important role in the mass balance of sea ice and the salt budget of the ocean. Sea ice formation is a complex process that starts with frazil ice crys- tal formation in supercooled waters, which grow and precipitate to the ocean surface to form grease ice, which eventually consolidates and turns into a layer of solid sea ice. This thesis looks at all three phases, concentrating on the first. Frazil ice comprises millimetre- sized crystals of ice that form in supercooled, turbulent water. They initially form through a process of seeding, and then grow and multiply through secondary nucleation, which is where smaller crystals break off from larger ones to create new nucleii for further growth. The increase in volume of frazil ice will continue to occur until there is no longer super- cooling in the water. The crystals eventually precipitate to the surface and pile up to form grease ice. The presence of grease ice at the ocean surface dampens the effects of waves and turbulence, which allows them to consolidate into a solid layer of ice. -
Article Sources and Dynamics, Other Seasons (Ducklow Et Al., 2015; Kim Et Al., 2015, 2019)
Biogeosciences, 16, 2683–2691, 2019 https://doi.org/10.5194/bg-16-2683-2019 © Author(s) 2019. This work is distributed under the Creative Commons Attribution 4.0 License. Collection of large benthic invertebrates in sediment traps in the Amundsen Sea, Antarctica Minkyoung Kim1, Eun Jin Yang2, Hyung Jeek Kim3, Dongseon Kim3, Tae-Wan Kim2, Hyoung Sul La2, SangHoon Lee2, and Jeomshik Hwang1 1School of Earth and Environmental Sciences/Research Institute of Oceanography, Seoul National University, Seoul, 08826, South Korea 2Korea Polar Research Institute, Incheon, 21990, South Korea 3Korea Institute of Ocean Science and Technology, Busan, 49111, South Korea Correspondence: Jeomshik Hwang ([email protected]) Received: 18 February 2019 – Discussion started: 6 March 2019 Revised: 4 June 2019 – Accepted: 18 June 2019 – Published: 11 July 2019 Abstract. To study sinking particle sources and dynamics, other seasons (Ducklow et al., 2015; Kim et al., 2015, 2019). sediment traps were deployed at three sites in the Amund- Biogeochemical processes related to biological pump in the sen Sea for 1 year from February–March 2012 and at one Amundsen Sea have been investigated by recent field cam- site from February 2016 to February 2018. Unexpectedly, paigns (Arrigo and Alderkamp, 2012; Yager et al., 2012; large benthic invertebrates were found in three sediment traps Meredith et al., 2016; Lee et al., 2017). deployed 130–567 m above the sea floor. The organisms in- Sediment traps were deployed in the Amundsen Sea to cluded long and slender worms, a sea urchin, and juvenile study sinking material flux and composition. Sampling oc- scallops of varying sizes.