Climate Change and Southern Ocean Resilience
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An Observation of Two Oceanic Salp Swarms in the Tasman Sea: Thetys Vagina and Cyclosalpa Affinis Natasha Henschke1,2,3*, Jason D
Henschke et al. Marine Biodiversity Records (2016) 9:21 DOI 10.1186/s41200-016-0023-8 MARINE RECORD Open Access An observation of two oceanic salp swarms in the Tasman Sea: Thetys vagina and Cyclosalpa affinis Natasha Henschke1,2,3*, Jason D. Everett1,2,3 and Iain M. Suthers1,2,3 Abstract Background: Large oceanic salps are rarely encountered. The highest recorded biomasses of the salps Thetys vagina (852 g WW m−3)andCyclosalpa affinis (1149 g WW m−3) were observed in the Tasman Sea during January 2009. Results: Due to their fast sinking rates the carcasses and faecal pellets of these and other large salps play a significant role in carbon transport to the seafloor. We calculated that faecal pellets from these swarms could have contributed up to 67 % of the mean organic daily carbon flux in the area. This suggests that the flux of carbon from salp swarms are not accurately captured in current estimates. Conclusion: This study contributes information on salp abundance and biomass to a relatively understudied field, improving estimates for biogeochemical cycles. Background (Henschke et al., 2013) can increase the carbon flux in an The role of gelatinous zooplankton, such as salps, pyro- area up to ten-fold the daily average (Fischer et al., 1988) somes and cnidarians, in ocean food webs and biogeo- for a sustained period of time (Smith et al. 2014). chemical cycling has garnered increased attention in Due to their regular occurrence (Henschke et al., recent years (Lebrato et al., 2011; Henschke et al., 2013; 2014) and coastal dominance (Henschke et al 2011), Lebrato et al., 2013; Smith et al. -
North America Other Continents
Arctic Ocean Europe North Asia America Atlantic Ocean Pacific Ocean Africa Pacific Ocean South Indian America Ocean Oceania Southern Ocean Antarctica LAND & WATER • The surface of the Earth is covered by approximately 71% water and 29% land. • It contains 7 continents and 5 oceans. Land Water EARTH’S HEMISPHERES • The planet Earth can be divided into four different sections or hemispheres. The Equator is an imaginary horizontal line (latitude) that divides the earth into the Northern and Southern hemispheres, while the Prime Meridian is the imaginary vertical line (longitude) that divides the earth into the Eastern and Western hemispheres. • North America, Earth’s 3rd largest continent, includes 23 countries. It contains Bermuda, Canada, Mexico, the United States of America, all Caribbean and Central America countries, as well as Greenland, which is the world’s largest island. North West East LOCATION South • The continent of North America is located in both the Northern and Western hemispheres. It is surrounded by the Arctic Ocean in the north, by the Atlantic Ocean in the east, and by the Pacific Ocean in the west. • It measures 24,256,000 sq. km and takes up a little more than 16% of the land on Earth. North America 16% Other Continents 84% • North America has an approximate population of almost 529 million people, which is about 8% of the World’s total population. 92% 8% North America Other Continents • The Atlantic Ocean is the second largest of Earth’s Oceans. It covers about 15% of the Earth’s total surface area and approximately 21% of its water surface area. -
The Antarctic Treaty System And
The Antarctic Treaty System and Law During the first half of the 20th century a series of territorial claims were made to parts of Antarctica, including New Zealand's claim to the Ross Dependency in 1923. These claims created significant international political tension over Antarctica which was compounded by military activities in the region by several nations during the Second World War. These tensions were eased by the International Geophysical Year (IGY) of 1957-58, the first substantial multi-national programme of scientific research in Antarctica. The IGY was pivotal not only in recognising the scientific value of Antarctica, but also in promoting co- operation among nations active in the region. The outstanding success of the IGY led to a series of negotiations to find a solution to the political disputes surrounding the continent. The outcome to these negotiations was the Antarctic Treaty. The Antarctic Treaty The Antarctic Treaty was signed in Washington on 1 December 1959 by the twelve nations that had been active during the IGY (Argentina, Australia, Belgium, Chile, France, Japan, New Zealand, Norway, South Africa, United Kingdom, United States and USSR). It entered into force on 23 June 1961. The Treaty, which applies to all land and ice-shelves south of 60° South latitude, is remarkably short for an international agreement – just 14 articles long. The twelve nations that adopted the Treaty in 1959 recognised that "it is in the interests of all mankind that Antarctica shall continue forever to be used exclusively for peaceful purposes and shall not become the scene or object of international discord". -
Lecture 21: Glaciers and Paleoclimate Read: Chapter 15 Homework Due Thursday Nov
Learning Objectives (LO) Lecture 21: Glaciers and Paleoclimate Read: Chapter 15 Homework due Thursday Nov. 12 What we’ll learn today:! 1. 1. Glaciers and where they occur! 2. 2. Compare depositional and erosional features of glaciers! 3. 3. Earth-Sun orbital parameters, relevance to interglacial periods ! A glacier is a river of ice. Glaciers can range in size from: 100s of m (mountain glaciers) to 100s of km (continental ice sheets) Most glaciers are 1000s to 100,000s of years old! The Snowline is the lowest elevation of a perennial (2 yrs) snow field. Glaciers can only form above the snowline, where snow does not completely melt in the summer. Requirements: Cold temperatures Polar latitudes or high elevations Sufficient snow Flat area for snow to accumulate Permafrost is permanently frozen soil beneath a seasonal active layer that supports plant life Glaciers are made of compressed, recrystallized snow. Snow buildup in the zone of accumulation flows downhill into the zone of wastage. Glacier-Covered Areas Glacier Coverage (km2) No glaciers in Australia! 160,000 glaciers total 47 countries have glaciers 94% of Earth’s ice is in Greenland and Antarctica Mountain Glaciers are Retreating Worldwide The Antarctic Ice Sheet The Greenland Ice Sheet Glaciers flow downhill through ductile (plastic) deformation & by basal sliding. Brittle deformation near the surface makes cracks, or crevasses. Antarctic ice sheet: ductile flow extends into the ocean to form an ice shelf. Wilkins Ice shelf Breakup http://www.youtube.com/watch?v=XUltAHerfpk The Greenland Ice Sheet has fewer and smaller ice shelves. Erosional Features Unique erosional landforms remain after glaciers melt. -
Salp Contributions to Vertical Carbon Flux in the Sargasso Sea
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by College of William & Mary: W&M Publish W&M ScholarWorks VIMS Articles Virginia Institute of Marine Science 2016 Salp contributions to vertical carbon flux in the Sargasso Sea JP Stone Virginia Institute of Marine Science Deborah K. Steinberg Virginia Institute of Marine Science Follow this and additional works at: https://scholarworks.wm.edu/vimsarticles Part of the Aquaculture and Fisheries Commons Recommended Citation Stone, JP and Steinberg, Deborah K., "Salp contributions to vertical carbon flux in the Sargasso Sea" (2016). VIMS Articles. 797. https://scholarworks.wm.edu/vimsarticles/797 This Article is brought to you for free and open access by the Virginia Institute of Marine Science at W&M ScholarWorks. It has been accepted for inclusion in VIMS Articles by an authorized administrator of W&M ScholarWorks. For more information, please contact [email protected]. 1 Salp contributions to vertical carbon flux in the Sargasso 2 Sea 3 4 5 Joshua P. Stonea,*, Deborah K. Steinberga 6 a Department of Biological Sciences, Virginia Institute of Marine Science, College of William & Mary, 7 PO Box 1346, Gloucester Point, VA 23062, USA 8 * Corresponding author. 9 E-mail addresses: [email protected] (J. Stone), [email protected] (D. Steinberg) 10 11 1 © 2016. This manuscript version is made available under the Elsevier user license http://www.elsevier.com/open-access/userlicense/1.0/ 12 Abstract 13 We developed a one-dimensional model to estimate salp contributions to vertical carbon flux at the 14 Bermuda Atlantic Time-series Study (BATS) site in the North Atlantic subtropical gyre for a 17-yr period 15 (April 1994 to December 2011). -
Coastal and Marine Ecological Classification Standard (2012)
FGDC-STD-018-2012 Coastal and Marine Ecological Classification Standard Marine and Coastal Spatial Data Subcommittee Federal Geographic Data Committee June, 2012 Federal Geographic Data Committee FGDC-STD-018-2012 Coastal and Marine Ecological Classification Standard, June 2012 ______________________________________________________________________________________ CONTENTS PAGE 1. Introduction ..................................................................................................................... 1 1.1 Objectives ................................................................................................................ 1 1.2 Need ......................................................................................................................... 2 1.3 Scope ........................................................................................................................ 2 1.4 Application ............................................................................................................... 3 1.5 Relationship to Previous FGDC Standards .............................................................. 4 1.6 Development Procedures ......................................................................................... 5 1.7 Guiding Principles ................................................................................................... 7 1.7.1 Build a Scientifically Sound Ecological Classification .................................... 7 1.7.2 Meet the Needs of a Wide Range of Users ...................................................... -
The Origins of Chordate Larvae Donald I Williamson* Marine Biology, University of Liverpool, Liverpool L69 7ZB, United Kingdom
lopmen ve ta e l B Williamson, Cell Dev Biol 2012, 1:1 D io & l l o l g DOI: 10.4172/2168-9296.1000101 e y C Cell & Developmental Biology ISSN: 2168-9296 Research Article Open Access The Origins of Chordate Larvae Donald I Williamson* Marine Biology, University of Liverpool, Liverpool L69 7ZB, United Kingdom Abstract The larval transfer hypothesis states that larvae originated as adults in other taxa and their genomes were transferred by hybridization. It contests the view that larvae and corresponding adults evolved from common ancestors. The present paper reviews the life histories of chordates, and it interprets them in terms of the larval transfer hypothesis. It is the first paper to apply the hypothesis to craniates. I claim that the larvae of tunicates were acquired from adult larvaceans, the larvae of lampreys from adult cephalochordates, the larvae of lungfishes from adult craniate tadpoles, and the larvae of ray-finned fishes from other ray-finned fishes in different families. The occurrence of larvae in some fishes and their absence in others is correlated with reproductive behavior. Adult amphibians evolved from adult fishes, but larval amphibians did not evolve from either adult or larval fishes. I submit that [1] early amphibians had no larvae and that several families of urodeles and one subfamily of anurans have retained direct development, [2] the tadpole larvae of anurans and urodeles were acquired separately from different Mesozoic adult tadpoles, and [3] the post-tadpole larvae of salamanders were acquired from adults of other urodeles. Reptiles, birds and mammals probably evolved from amphibians that never acquired larvae. -
GSA TODAY • Southeastern Section Meeting, P
Vol. 5, No. 1 January 1995 INSIDE • 1995 GeoVentures, p. 4 • Environmental Education, p. 9 GSA TODAY • Southeastern Section Meeting, p. 15 A Publication of the Geological Society of America • North-Central–South-Central Section Meeting, p. 18 Stability or Instability of Antarctic Ice Sheets During Warm Climates of the Pliocene? James P. Kennett Marine Science Institute and Department of Geological Sciences, University of California Santa Barbara, CA 93106 David A. Hodell Department of Geology, University of Florida, Gainesville, FL 32611 ABSTRACT to the south from warmer, less nutrient- rich Subantarctic surface water. Up- During the Pliocene between welling of deep water in the circum- ~5 and 3 Ma, polar ice sheets were Antarctic links the mean chemical restricted to Antarctica, and climate composition of ocean deep water with was at times significantly warmer the atmosphere through gas exchange than now. Debate on whether the (Toggweiler and Sarmiento, 1985). Antarctic ice sheets and climate sys- The evolution of the Antarctic cryo- tem withstood this warmth with sphere-ocean system has profoundly relatively little change (stability influenced global climate, sea-level his- hypothesis) or whether much of the tory, Earth’s heat budget, atmospheric ice sheet disappeared (deglaciation composition and circulation, thermo- hypothesis) is ongoing. Paleoclimatic haline circulation, and the develop- data from high-latitude deep-sea sed- ment of Antarctic biota. iments strongly support the stability Given current concern about possi- hypothesis. Oxygen isotopic data ble global greenhouse warming, under- indicate that average sea-surface standing the history of the Antarctic temperatures in the Southern Ocean ocean-cryosphere system is important could not have increased by more for assessing future response of the Figure 1. -
Towards an Understanding of Salp Swarm Dynamics. ICES CM 2002/N
CM 2002/ N:12 Towards an understanding of salp swarm dynamics by Patricia Kremer ABSTRACT Species of salps are characterized by intermittent blooms. Several studies have documented the importance of physical processes both in providing seed stocks of salps and creating an environment that is favorable for the rapid increase of salp populations. Although salps are typically oceanic, most observations of bloom dynamics have been made in more accessible inshore waters, so it is difficult to assess how frequent and widespread these swarms are. A review and comparison of existing data is helping to define geographic “hot spots” for salp blooms as well as the necessary physical and biological precursors. Although at this point, the review is far from complete, several generalities are emerging. The details of the physical forcing functions vary, but the overall physical regime seems to require a region of pulsed mixing of oceanic water that results in a relatively high standing stock of autotrophs. For a salp bloom to occur, there also needs to be an adequate seed population of salps and sufficient sustained primary production to support the biomass of the salp population as the bloom develops. As non-selective filter feeders, salps are able to remove a wide range of particulates from the water column, transforming the undigested portion into fast sinking feces. Therefore, when salps occur at high densities, the water is characterized by low abundance of other plankton, with obvious trophic implications. Patricia Kremer: Marine Sciences, University of Connecticut, Groton CT 06340-6097, USA [tel: +1 860 405 9140; fax: +1 860 405 9153; e-mail [email protected]] INTRODUCTION Salps are holoplanktonic grazers that have a life history, feeding biology, and population dynamics that contrasts sharply to copepods and other crustacean zooplankton (Madin and Deibel 1998). -
Antarctic Primer
Antarctic Primer By Nigel Sitwell, Tom Ritchie & Gary Miller By Nigel Sitwell, Tom Ritchie & Gary Miller Designed by: Olivia Young, Aurora Expeditions October 2018 Cover image © I.Tortosa Morgan Suite 12, Level 2 35 Buckingham Street Surry Hills, Sydney NSW 2010, Australia To anyone who goes to the Antarctic, there is a tremendous appeal, an unparalleled combination of grandeur, beauty, vastness, loneliness, and malevolence —all of which sound terribly melodramatic — but which truly convey the actual feeling of Antarctica. Where else in the world are all of these descriptions really true? —Captain T.L.M. Sunter, ‘The Antarctic Century Newsletter ANTARCTIC PRIMER 2018 | 3 CONTENTS I. CONSERVING ANTARCTICA Guidance for Visitors to the Antarctic Antarctica’s Historic Heritage South Georgia Biosecurity II. THE PHYSICAL ENVIRONMENT Antarctica The Southern Ocean The Continent Climate Atmospheric Phenomena The Ozone Hole Climate Change Sea Ice The Antarctic Ice Cap Icebergs A Short Glossary of Ice Terms III. THE BIOLOGICAL ENVIRONMENT Life in Antarctica Adapting to the Cold The Kingdom of Krill IV. THE WILDLIFE Antarctic Squids Antarctic Fishes Antarctic Birds Antarctic Seals Antarctic Whales 4 AURORA EXPEDITIONS | Pioneering expedition travel to the heart of nature. CONTENTS V. EXPLORERS AND SCIENTISTS The Exploration of Antarctica The Antarctic Treaty VI. PLACES YOU MAY VISIT South Shetland Islands Antarctic Peninsula Weddell Sea South Orkney Islands South Georgia The Falkland Islands South Sandwich Islands The Historic Ross Sea Sector Commonwealth Bay VII. FURTHER READING VIII. WILDLIFE CHECKLISTS ANTARCTIC PRIMER 2018 | 5 Adélie penguins in the Antarctic Peninsula I. CONSERVING ANTARCTICA Antarctica is the largest wilderness area on earth, a place that must be preserved in its present, virtually pristine state. -
Glacier (And Ice Sheet) Mass Balance
Glacier (and ice sheet) Mass Balance The long-term average position of the highest (late summer) firn line ! is termed the Equilibrium Line Altitude (ELA) Firn is old snow How an ice sheet works (roughly): Accumulation zone ablation zone ice land ocean • Net accumulation creates surface slope Why is the NH insolation important for global ice• sheetSurface advance slope causes (Milankovitch ice to flow towards theory)? edges • Accumulation (and mass flow) is balanced by ablation and/or calving Why focus on summertime? Ice sheets are very sensitive to Normal summertime temperatures! • Ice sheet has parabolic shape. • line represents melt zone • small warming increases melt zone (horizontal area) a lot because of shape! Slightly warmer Influence of shape Warmer climate freezing line Normal freezing line ground Furthermore temperature has a powerful influence on melting rate Temperature and Ice Mass Balance Summer Temperature main factor determining ice growth e.g., a warming will Expand ablation area, lengthen melt season, increase the melt rate, and increase proportion of precip falling as rain It may also bring more precip to the region Since ablation rate increases rapidly with increasing temperature – Summer melting controls ice sheet fate* – Orbital timescales - Summer insolation must control ice sheet growth *Not true for Antarctica in near term though, where it ʼs too cold to melt much at surface Temperature and Ice Mass Balance Rule of thumb is that 1C warming causes an additional 1m of melt (see slope of ablation curve at right) -
Biomass of Zooplankton and Micronekton in the Southern Bluefin Tuna Fishing Grounds Off Eastern Tasmania, Australia
-- MARINE ECOLOGY PROGRESS SERIES Vol. 138: 1-14, 1996 Published July 25 , Mar Ecol Prog Ser Biomass of zooplankton and micronekton in the southern bluefin tuna fishing grounds off eastern Tasmania, Australia J. W. Young*, R. W. Bradford, T. D. Lamb, V. D. Lyne CSIRO Marine Laboratories, Division of Fisheries. GPO Box 1538. Hobart 7001, Tasmania, Australia ABSTRACT: The southern bluefin tuna (SBT) supports a seasonal fishery off the east coast of Tasmania, Australia. The distribution of zooplankton biomass in this region was examined as a means of finding out why the SBT are attracted to this area. We examined whether there was a particular area or depth stratum that supported significantly greater amounts of potential feed, directly or indirectly, for SBT Samples of zooplankton and micronekton were collected during the winter SBT fishery seasons in 1992-94. Five net types (mouth opening 0 25 to -80 m') w~thcodend mesh sizes ranging from 100 to 1000 pm were used. Samples were collected from 4 main hydrographic areas: warm East Australian Current water, cool subantarctic water, the front separating them (the subtrop~calconvergence), and the adjacent shelf. Four depth strata (50, 150, 250 and 350 m) were also sampled. In contrast to our expectations, the biomass in the subtropical convergence was no greater than that in the 3 other areas. Rather, it was the shelf, albeit with some inconsistencies, that generally had the greatest biomass of both zooplankton and micronekton. Offshore, there was no s~gnificantdifference in the biomass of the depth strata sampled, although the biomass of gelatinous zooplankton in the surface waters increased during the study period.