2,428 research outputs found
Variability of Antarctic Bottom Water at 24.5°N in the Atlantic
A recent hydrographic section at 24.5°N in the Atlantic and 6 months of observations from a moored array show that Antarctic Bottom Water (AABW), the densest and deepest water mass in the world oceans, has been warming. While Johnson et al. (2008) showed that northward AABW transport at 24.5°N has been declining from 1981 to 2004, suggesting that the lower cell of the overturning circulation could halt in the near future, estimates from the latest hydrographic section in 2010 indicate a partial recovery of northward AABW transport. From 6 months of temperature and salinity observations at a deep moored array at 24–26°N, we find that short-term variability between April and November 2009 is of the same magnitude as the changes observed from hydrographic sections between 1981 and 2004. These observations highlight the possibility that transport changes estimated from hydrographic sections may be aliased by short-term variability. The observed AABW transport variability affects present estimates of the upper meridional overturning circulation by ±0.4 Sv (1 Sv = 106 m3 s?1)
Survey report 1978/79 Glaciology department Author - B.A. Murphy
Progress Code: completedStatement: See the report for further information.
The values provided in spatial coverage are approximate only. The values provided in temporal coverage are based on the assumption that B.A. Murphy travelled to and from Davis by scheduled Australian Antarctic voyages.Taken from sections of the report:<br/><br/>Introduction:<br/><br/>The following report is a detailed summary of the surveying and mapping tasks undertaken in the Vestfold Hills and Mac. Robertson Land regions of the Australian Antarctic Territory during the period from 22 December 1978 to 25 February 1979. A copy of the project instruction detailing the tasks originally intended to be undertaken is attached at Annex 37.<br/><br/>The entire report is available as a pdf download from the URL given below
Shakespeare's Playhouse
(Statement of Responsibility) by Kevin Cunningham(Thesis) Thesis (B.A.) -- New College of Florida, 2001RESTRICTED TO NCF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE(Bibliography) Includes bibliographical references.This bibliographic record is available under the Creative Commons CC0 public domain dedication. The New College of Florida, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.Faculty Sponsor: Miller, Arthu
Atlantic transport variability at 25°N in six hydrographic sections
In January and February 2010, a sixth transatlantic hydrographic section was completed across 25° N, extending the hydrographic record at this latitude to over half a century. In combination with continuous transport measurements made since 2004 at 26° N by the Rapid-WATCH project, we reassess transport variability in the 25° N hydrographic record. Past studies of transport variability at this latitude have assumed transport estimates from each hydrographic section to represent annual average conditions. In this study the uncertainty in this assumption is assessed through use of Rapid-WATCH observations to quantify sub-seasonal and seasonal transport variability. Whilst in the upper-ocean no significant interannual or decadal transport variability are identified in the hydrographic record, in the deep ocean transport variability in both depth and potential temperature classes suggests some interannual or decadal variability may have occurred. This is particularly striking in the lower North Atlantic Deep Water where southward transports prior to the 1990s were higher than recent transports by several Sverdrups. Whilst a cooling and freshening of Denmark Straits Overflow Water has occurred which is coincident with these transport changes, these water mass changes appear to be density compensated. Transport changes are the result of changing velocity shear in the vicinity of the Deep Western Boundary Current
Subpolar North Atlantic overturning and gyre-scale circulation in the summers of 2014 and 2016
The Atlantic Meridional Overturning Circulation (AMOC) is a key component of the global climate system through its transport of heat and freshwater. The subpolar North Atlantic (SPNA) is a region where the AMOC is actively developed and shaped though mixing and water mass transformation, and where large amounts of heat are released to the atmosphere. Two hydrographic trans‐basin sections in the summers of 2014 and 2016 provide highly spatially resolved views of the SPNA velocity and property fields on a line from Canada to Greenland to Scotland. Estimates of the AMOC, isopycnal (gyre‐scale) transport, and heat and freshwater transport are derived from the observations. The overturning circulation, the maximum in northward transport integrated from the surface to seafloor and computed in density space, has a high range, with 20.6 ± 4.7 Sv in June‐July 2014 and 10.6 ± 4.3 Sv in May‐August 2016. In contrast the isopycnal (gyre‐scale) circulation was lowest in summer 2014: 41.3 ± 8.2 Sv compared to 58.6 ± 7.4 Sv in 2016. The heat transport (0.39 ± 0.08 PW in summer 2014, positive is northwards) was highest for the section with the highest AMOC, and the freshwater transport was largest in summer 2016 when the isopycnal circulation was high (‐0.25 ± 0.08 Sv). Up to 65% of the heat and freshwater transport was carried by the isopycnal circulation, with isopycnal property transport highest in the western Labrador Sea and the eastern basins (Iceland Basin to Scotland)
TRAVERSING TRAUMA, TRANSFORMING SELF
(Statement of Responsibility) by Zoe Cunningham(Thesis) Thesis (B.A.) -- New College of Florida, 2013(Electronic Access) RESTRICTED TO NCF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE(Bibliography) Includes bibliographical references.(Source of Description) This bibliographic record is available under the Creative Commons CC0 public domain dedication. The New College of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.(Local) Faculty Sponsor: Miles, Stephe
Modeling Nonheme Iron Enzymes with the Monoanionic Heteroscorpionate Ligand Bdippza
(Statement of Responsibility) by Laura Cunningham(Thesis) Thesis (B.A.) -- New College of Florida, 2013(Electronic Access) RESTRICTED TO NCF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE(Bibliography) Includes bibliographical references.(Source of Description) This bibliographic record is available under the Creative Commons CC0 public domain dedication. The New College of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.(Local) Faculty Sponsor: Sherman, Suzann
Transport and variability of the Antarctic Circumpolar Current in Drake Passage
The baroclinic transport of the Antarctic Circumpolar Current (ACC) above 3000 m through Drake Passage is 107.3 ± 10.4 Sv and has been steady between 1975 and 2000. For six hydrographic sections (1993–2000) along the World Ocean Circulation Experiment (WOCE) line SR1b, the baroclinic transport relative to the deepest common level is 136.7 ± 7.8 Sv. The ACC transport is carried in two jets, the Subantarctic Front 53 ± 10 Sv and the Polar Front (PF) 57.5 ± 5.7 Sv. Southward of the ACC the Southern Antarctic Circumpolar Current transports 9.3 ± 2.4 Sv. We observe the PF at two latitudes separated by 90 km. This bimodal distribution is related to changes in the circulation and properties of Antarctic Bottom Water. Three realizations of the instantaneous velocity field were obtained with lowered ADCPs. From these observations we obtain near-bottom reference velocities for transport calculations. Net transport due to these reference velocities ranges from -28 to 43 Sv, consistent with previous estimates of variability. The transport in density layers shows systematic variations due to seasonal heating in near-surface layers. Volume transport-weighted mean temperatures vary by 0.40°C from spring to summer; a seasonal variation in heat flux of about 0.22 PW. Finally, we review a series of papers from the International Southern Ocean Studies Program. The average yearlong absolute transport is 134 Sv, and the standard deviation of the average is 11.2 Sv; the error of the average transport is 15 to 27 Sv. We emphasize that baroclinic variability is an important contribution to net variability in the ACC
Emma Sandberg : B.A., 1925
Married Frances Thomas Cunningham ; Teacher at Florida, New York and Colorado Schoolshttps://ida.gallaudet.edu/alumni-cards/2600/thumbnail.jp
Benchmarking the digital maturity of the Dutch Health Insurance Companies: with the application of a PCA-DEA model
Technology, Policy and ManagementSystems engineering policy analysis and managemen
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