88 research outputs found
All identification photos taken of whales during the NZ-Australia Antarctic Ecosystems Voyage to the Ross Sea 2015
No full textProgress Code: completed<b>Purpose</b><br/>Individual identification allows the production of sightings histories required for a mark-recapture approach to estimating abundance. These data will also provide information on whale population structure and movement.All photos taken during the NZ-Australia Antarctic Ecosystems Voyage on the RV Tangaroa to the Ross Sea 2015 in an attempt to get a best photo identification image of blue whales, killer whales, humpback whales and minke whales. Image collection location and other details such as photographer, species, date (UTC) can be found in excel spreadsheet. A scan of all photo ID data forms is also included and contains further detail on each photographic event.<br/><br/>Photo-identification images of whales are collected using digital SLR cameras. Individual blue whales are identifiable from unique patterns of mottled pigment on both sides of the body, and also from variations in dorsal fin shape and any permanent scars that may be present. Blue whales will be photographed at an angle perpendicular to the whale, capturing the pigmentation in the area of the dorsal fin. Individual humpback whales are identifiable from photographs of the ventral flukes or the dorsal fin (perpendicular angle) if the whale does not fluke up
Macrourus caml Mcmillan, Iwamoto, Stewart & Smith, 2012, sp. nov.
No full textMacrourus caml sp. nov. Caml grenadier Macrourus whitsoni (in part not Regan 1913): Trunov & Konstantinov, 1989: 54–65 (97 specimens, description, compared with M. carinatus, in Russian, English summary). Marriott et al., 2003: 39–41 (364 specimens, Ross Dependency). Diagnosis. Ventral surface of the head mostly scaled, except for scaleless areas anterior to the mouth and on the anterior half of the lower jaw. Pelvic fin with 8 rays, rarely 7 or 9. Lower jaw with 2–3 rows of small pointed uniform-sized teeth reducing to a single row posteriorly. Upper jaw with 4–5 rows of small, uniform-sized teeth. Body scales small, 30–40 in a diagonal row from anal fin origin to lateral line. Pyloric caeca 20–37. Specimens examined. Holotype. NMNZ P.043633 (123 mm HL, 589 + mm TL), Ross Sea slope, Antarctica, 72 º 21 ' S, 175 º 33 ' E, 945–952 m, RV Tangaroa, IPY/ CAML TAN 0802/ 121, bottom trawl, 21 Feb 2008. Paratypes (33). AMS I. 45750 -001 ex NMNZ P.037602 (102 mm HL, 456 mm TL), Ross Sea slope, 73 º 56 ' S, 176 º 53 ' W, 838–922 m, FV Janas, OBS 1302 / 126, bottom longline, 21 Feb 2000; BMNH 2011.8. 1.1 ex NMNZ P. 9372 (118 mm HL, 577 mm TL), Ross Sea slope, 73 º 15 ' S, 177 º 18 ' W, 940–1211 m, FV Janas, OBS 1181 /027, bottom longline, 19 Jan 1999; CAS 233433 ex NMNZ P.043997 (102 mm HL, 479 mm TL), Ross Sea slope, 73 º 15 ' S, 178 º 44 ' E, 760–770 m, RV Tangaroa, IPY/ CAML TAN 0802/ 106, bottom trawl, 19 Feb 2008; CSIRO H 7251 -01 ex NMNZ P.043592 (77 mm HL, 359 mm TL), Ross Sea slope, 73 º 15 ' S, 178 º 44 ' E, 760–770 m, RV Tangaroa, IPY/ CAML TAN 0802/ 106, bottom trawl, 19 Feb 2008; MNHN: 2011 -0280 ex NMNZ P. 040371 (62 mm HL, 279 mm TL), Balleny Islands, 66 º 33 ' S, 163 º 1 ' E, 550–574 m, RV Tangaroa, TAN 0402/ 249, bottom trawl, 0 5 Mar 2004; NMNZ P.036091 (168 mm HL, 767 mm TL), Ross Sea slope, 72 º 3 ' S, 173 º 35 ' E, 885–1038 m, FV Janas, OBS 1181 / 109, bottom longline, 17 Feb 1999; NMNZ P.036104 (119 mm HL, 580 mm TL), Ross Sea slope, 73 º 15 ' S, 177 º 18 ' W, 940–1211 m, FV Janas, OBS 1181 /027, bottom longline, 19 Jan 1999; NMNZ P.036142 (104 mm HL, 380 mm TL), NMNZ P.036173 (115 mm HL, 425 mm TL), Ross Sea slope, 73 º 1 ' S, 176 º 53 ' E, 863–919 m, FV San Aotea II, OBS 1180 /004, bottom longline, 14 Jan 1999; NMNZ P.036174 (84 mm HL, 370 mm TL), Ross Sea slope, 71 º 27 ' S, 178 º 40 ' W, 1020–1111 m, FV San Aotea II, OBS 1180 / 103, bottom longline, 15 Feb 1999; NMNZ P.036988 (3, 99– 103 mm HL, 465–469 mm TL), South Georgia, 54 º 0' S, 39 º 0' W, 1300–2000 m, Apr 1997; NMNZ P.037599 (126 mm HL, 485 mm TL), Ross Sea slope, 74 º 23 ' S, 176 º 33 ' W, 896 – 896 m, FV Janas, OBS 1302 / 144, bottom longline, 26 Feb 2000; NMNZ P.037602 (2, 103 – 122 mm HL, 433–542 mm TL), Ross Sea slope, 73 º 56 ' S, 176 º 53 ' W, 838–922 m, FV Janas, OBS 1302 / 126, bottom longline, 21 Feb 2000; NMNZ P.037603 (99 mm HL, 439 mm TL), Ross Sea slope, 74 º 16 ' S, 176 º 53 ' W, 786–796 m, FV Janas, OBS 1302 / 139, bottom longline, 25 Feb 2000; NMNZ P.037762 (2, 114 – 121 mm HL, 536–554 mm TL), Ross Sea slope, 69 º 21 ' S, 178 º 39 ' W, 425–1661 m, FV Janas, OBS 1429 / 122, bottom longline, 20 Feb 2001; NMNZ P.038635 (131 mm HL, 533 mm TL), Scott Island seamounts, 68 º 2 ' S, 179 º 7 ' W, 1010–1156 m, FV San Aotea II, OBS 1595 B/ 138, bottom longline, 18 Apr 2002; NMNZ P.038793 (184 mm HL, 890 mm TL), Ross Sea slope, 71 º 15 ' S, 176 º 36 ' E, 1440 m, FV San Aotea II, OBS 1725 /041, bottom longline, 22 Jan 2003; NMNZ P. 040634 (2, 102 – 112 mm HL, 445–461 mm TL), Ross Sea slope, 71 º 31 ' S, 178 º 45 ' W, 1168–1251 m, FV Gudni Olafsson, OBS 1843 /075, bottom longline, 10 Feb 2004; NMNZ P. 041446 (132 mm HL, 625 mm TL), Cosmonaut Sea, 66 º 19 ' S, 33 º 14 ' E, 1317–1334 m, FV Janas, OBS 2068 /033, bottom longline, 26 Mar 2005; NMNZ P. 042222 (147 mm HL, 722 mm TL), Pacific-Antarctic Ridge, 66 º 30 ' S, 176 º 23 ' W, 1660–2080 m, FV Avro Chieftain, OBS 2186 /006, bottom longline, 22 Dec 2005; NMNZ P. 042353 (128 mm HL, 618 mm TL), Ross Sea slope, 72 º 39 ' S, 179 º 35 ' W, 762–793 m, FV Sonrisa, OBS 1311 /001, bottom longline, 30 Jan 2000; NMNZ P. 042587 (123 mm HL, 527 mm TL), South Georgia, 54 º 39 ' S, 39 º 3 ' W, 1260 m,, FV San Aspiring, OBS 2234 / 123, bottom longline, 0 6 Jul 2006; NMNZ P. 042591 (147 mm HL, 720 mm TL), South Georgia, 53 º 13 ' S, 42 º 7 ' W, 1280 m,, FV San Aspiring, OBS 2234 / 236, bottom longline, 27 Aug 2006; NMNZ P.043591 (87 mm HL, 319 mm TL); NMNZ P.043683, (123 mm HL, 598 mm TL), Ross Sea slope, 71 º 56 ' S, 173 º 18 ' E, 1431–1658 m, RV Tangaroa, IPY/ CAML TAN 0802/ 144, bottom trawl, 23 Feb 2008; NMNZ P.043997 (122 mm HL, 573 mm TL), Ross Sea slope, 73 º 15 ' S, 178 º 44 ' E, 760–770 m, RV Tangaroa, IPY/ CAML TAN 0802/ 106, bottom trawl, 19 Feb 2008; NMNZ P.045643 (41 mm HL, 184 mm TL), Scott Island seamounts, 68 º 7 ' S, 179 º 15 ' W, 855–879 m, RV Tangaroa, IPY/ CAML TAN 0802/ 211, bottom trawl, 0 3 Mar 2008; USNM 402714 ex NMNZ P. 040102 (68 mm HL, 321 mm TL), Ross Sea slope, 71 º 30 ' S, 171 º 48 ' E, 540–549 m, RV Tangaroa, TAN 0402/ 172, bottom trawl, 27 Feb 2004. Non-type specimens (28). NMNZ P.038623 (115 mm HL, 405 mm TL), Ross Sea slope, 71 º 48 ' S, 177 º 26 ' W, 757–784 m, FV Janas, OBS 1593 A/034, bottom longline, 26 Jan 2002; NMNZ P. 040263 (10, 38– 50 mm HL, 174–236 mm TL), Balleny Islands, 67 º 15 ' S, 164 º 51 ' E, 348–353 m, RV Tangaroa, TAN 0402/ 218, bottom trawl, 0 3 Mar 2004; NMNZ P. 040322 (7, 26– 59 mm HL, 132–274 mm TL), Balleny Islands, 66 º 33 ' S, 163 º 1 ' E, 550– 574 m, RV Tangaroa, TAN 0402/ 249, bottom trawl, 0 5 Mar 2004; NMNZ P. 040370 (80 mm HL, 360 mm TL), Balleny Islands, 66 º 41 ' S, 162 º 46 ' E, 377–383 m, RV Tangaroa, TAN 0402/ 246, bottom trawl, 0 5 Mar 2004; NMNZ P.043590 (6, 20– 63 mm HL, 108–301 mm TL), Ross Sea slope, 73 º 15 ' S, 178 º 44 ' E, 760–770 m, RV Tangaroa, IPY/ CAML TAN 0802/ 106, bottom trawl, 19 Feb 2008; NMNZ P.043883 (38 mm HL, 170 mm TL), Admiralty seamount, 66 º 59 ' S, 170 º 51 ' E, 445–455 m, RV Tangaroa, IPY/ CAML TAN 0802/ 265, bottom trawl, 10 Mar 2008; NMNZ P.043890 (2, 21– 35 mm HL, 83–160 mm TL), Admiralty seamount, 67 º 7 ' S, 170 º 56 ' E, 543–545 m, RV Tangaroa, IPY/ CAML TAN 0802/ 279, epibenthic sled, 11 Mar 2008. Counts and measurements (Tables 1 –2). Description (Figures 2–4, Tables 1 –2). Head large, length 3.2 to 5.5 into total length. Moderately strong scutes on head ridges, armed with short spinules. Blunt, slightly rounded snout, length less than orbit diameter, tipped with a prominent scute. Upper jaw about same length as orbit diameter, posterior end of premaxilla below or just behind mid-orbit. Chin barbel about one-third of orbit diameter. Teeth in both jaws small, pointed, may be slightly curved inwards. Upper jaw teeth in 3–5 rows with outer teeth not noticeably enlarged relative to those of inner rows. Lower jaw closely spaced with 2–4 rows at tip, reducing to 1–2 rows posteriorly, outer teeth not noticeably enlarged. Origin of pelvic fin slightly in advance of pectoral fin, and both slightly in advance of origin of first dorsal fin. First dorsal height and pectoral fin length relatively large compared to others in genus. Body scales small, deciduous. Those between lateral line and first dorsal fin base with a central long row of enlarged spinules and 3–4 short rows of small spinules on each side. Lower body scales mostly lack a central row of spinules. Dorsal head covered with adherent scales, except for scaleless area around nostrils that extends dorsally to nasal ridge and ventrally to suborbital ridge. Ventral surface of snout anterior to mouth scaleless. Numerous rows of small flat scales lacking spinules at posterior end of ventral surface of head, extending forward to about level with anterior end of orbit and reducing to 1–2 rows anteriorly. Small scales on rear one-third to half of lower jaw in 1–3 rows. Fresh colour of head and body medium to dark brownish or blackish with smaller specimens paler. Sides of head and trunk of large specimens may have greenish iridescence. Bluish abdominal area below about upper edge of pectoral fin base in smaller individuals, but not obvious in larger ones. Lining of mouth and gill cavity greyishblack. Lips brownish. Ventral snout dark brownish with numerous pale pore openings. Fins brownish in smaller and blackish in larger specimens. Preserved specimens brownish or blackish overall. Size. To at least 890 mm TL and about 4.4 kg. Distribution (Figure 5 A). Probably widespread in the Southern Ocean including the Ross Sea, Balleny and Scott Islands slope, Cosmonaut Sea (33 E), south of South Georgia (54 S), at 350–2080 m. Etymology. Named for the Census of Antarctic Marine Life (CAML, pronounced ‘camel’) carried out in International Polar Year (2008). Treated as a noun in apposition to the genus name (International Commission on Zoological Nomenclature, 1999). Comparisons and remarks (Table 3). Previously confused with Macrourus whitsoni. The first author participated in two biodiversity surveys of the Ross Sea (2004 & 2008) but did not recognise the presence of the two species of Macrourus during initial sorting of catches. DNA analysis (C01) of tissue samples collected during the 2008 IPY surveys indicated four clades among the Southern Ocean specimens: M. carinatus, M. holotrachys, M. whitsoni, and an undescribed species (Fig 2, Smith et al. 2011). Meristic and morphometric examination of Te Papa collection specimens resulted in the conclusion that there were two sympatric species. M. whitsoni has more pelvic fin rays (9, rarely 10), usually a single row (may be 2 rows at tip) of long, spaced, teeth in the lower jaw, upper jaw with 3–5 rows of teeth with outer row slightly enlarged relative to inner rows, 15–26 pyloric caeca. M. carinatus has larger body scales with 19–25 in a diagonal row from anal fin origin to lateral line, fewer pyloric caeca 13–20, and upper jaw has an outer row of slightly enlarged teeth. M. berglax from the northern hemisphere and M. holotrachys from the southern hemisphere usually have an almost scaleless ventral surface of the head. Trunov and Konstantinov (1989) reported numerous specimens of what they identified as Macrourus whitsoni from the Southern Ocean. But it is very likely that their material included both M. caml and M. whitsoni because their reported counts of pelvic fin rays, pyloric caeca, and scales from anal fin origin to lateral line mostly straddle the counts made by us for the two separate species (Table 4). Macrourus caml appears to be abundant in the Ross Sea region and there are numerous specimens of the new species in the Te Papa collection. Many were collected by observers from bottom longline vessels fishing for Antarctic and Patagonian toothfish. Both M. caml and M. whitsoni appear to readily take baited hooks and are a substantial part of the fishery bycatch (Hanchet et al. 2008). Both species have been taken on the same bottom longline set and appear to occupy similar depths although M. whitsoni appears to extend to slightly greater depths. The slightly smaller and more subterminal mouth of M. caml suggests a more benthic diet compared to M. whitsoni which has a slightly larger gape, more terminal mouth and longer teeth. The method of capture (bottom longline and trawl) usually results in the expansion of the gas (swim) bladder and an everted stomach, making feeding study difficult.Published as part of Mcmillan, Peter, Iwamoto, Tomio, Stewart, Andrew & Smith, Peter J, 2012, A new species of grenadier, genus Macrourus (Teleostei, Gadiformes, Macrouridae) from the southern hemisphere and a revision of the genus, pp. 1-24 in Zootaxa 3165 on pages 4-9, DOI: 10.5281/zenodo.27973
Preventing induced abortion among urban poor in Fortaleza, Brazil : is post-abortion counselling effective?.
No full textThis thesis reports the results of a randomised controlled intervention study carried out
between May and November 1993 in a major public hospital in the metropolitan area of
Fortaleza City, Ceará, Brazil. The objective was to investigate the impact of post abortion counselling on uptake of contraception and on subsequent pregnancy and
abortion.
The study population was a sample of women hospitalised with complications of
induced abortion which were identified during as larger hospital-based study on abortion.
The intervention was half an hour of contraceptive counselling prior to discharge at the
study site hospital. No contraceptive method was given. A total of 695 women were
enrolled into the study, 345 in the intervention group and 350 in the control group.
They were followed up at home at 2 weeks, 6 weeks, 4 months, 8 months and 1 year
after discharge. Data were collected by trained interviewers using a structured
questionnaire. Outcome measures of interest were; knowledge of contraceptive
methods, seeking contraceptive services, uptake of contraception, having unprotected
sexual intercourse, subsequent pregnancies and subsequent abortion.
The study results show that this particular mode of counselling (single shot hospital-based post-abortion) increased the level of knowledge of some contraceptive methods,
but did not have any effect in changing behaviour such as seeking contraceptive services,
uptake of contraception or having unprotected sexual relationship. As a consequence,
counselling did not show any impact on preventing another unwanted pregnancy and induced abortion. Among 695 women, 165 (23.7%) became pregnant again before the
end of the 1 year follow-up; 81 (23.5%) in the intervention group and 84 (24.0%) in the
control group. Of the 695 women, 42 (6.0%) had another abortion before the end of
the 1 year follow-up; 27 (7.8%) in the intervention group and 15 (4.3%) in the control
group. At 6 weeks visit, of the 662 women interviewed, 345 (52.1%) were using
contraceptive methods; 178 (53.8%) in the intervention group and 167 (50.5%) in the
control group. Women who were not using contraception after abortion tended to be
young, single or without a partner. "Not having sexual intercourse" was the most
frequently cited reason for not using a contraceptive method during the follow-up period.
Suggestions were made on how a more effective intervention that might prove more
successful in responding to these women' s needs for enhanced contraception can be
developed
Abundance of benthic peracarids sampled in the Atlantic Sector of the Southern Ocean and Weddell Sea during expeditions JR15005, JR275, JR17003a, PS118
No full textPeracarid abundance and composition were studied in the Atlantic Sector of the Southern Ocean and the Weddell Sea at a depth range of 403-2021 m. Samples were collected using an epibenthic sledge (EBS) during expeditions on board the RRS James Clarke Ross in the Filchner Trough (JR275), the South Orkney Islands (JR15005), the Prince Gustav Channel (JR17003a) and on board the RV Polarstern in the Eastern Antarctic Peninsula (PS118). Expeditions took place in February-March 2012, 2016, 2018 and 2019 respectively. Since the trawling distance between stations was not always the same, in order to make data comparable between different stations, numbers of individuals were standardized to 1000 m haul distances.
In total 64766 peracarids were found and sorted into five different orders (Amphipoda, Cumacea, Isopoda, Mysidacea and Tanaidacea). Amphipods were the most abundant group representing the 32% of the total abundances. The Filchner Trough had the highest abundance of peracarids, while the South Orkney Islands showed the lowest abundance compared to other areas
Decreased time constant of the pulmonary circulation in chronic thromboembolic pulmonary hypertension
No full textThis study analysed the relationship between pulmonary vascular resistance (PVR) and compliance (Ca) in patients with idiopathic pulmonary arterial hypertension (IPAH) and proximal chronic thromboembolic pulmonary hypertension (CTEPH). It has recently been shown that the time constant of the pulmonary circulation (RC-time), or PVR x Ca, remains unaltered in various forms and severities of PH, with the exception of left heart failure. We reasoned that increased wave reflection in proximal CTEPH would be another cause of decreased RC-time. We conducted a retrospective analysis of invasive pulmonary hemodynamic measurements in IPAH (n=78), proximal CTEPH (n=91) before and after pulmonary endarterectomy (PEA) and distal CTEPH (n=53). Proximal CTEPH was defined by a postoperative mean pulmonary artery pressure (mPAP) ≤ 25 mmHg. Outcome measures were the RC-time, PVR, Ca and the relationship between systolic and mean pulmonary artery pressures. The RC time for Pre-PEA CTEPH was 0.49 ± 0.11s compared with Post PEA-CTEPH 0.37 ± 0.11s (p<0.0001), IPAH 0.63 ± 0.14s (p<0.001) and Distal CTEPH 0.55 ± 0.12s (p<0.05). A shorter RC-time was associated with a disproportionate decrease in systolic PAP with respect to mPAP. We concluded that the pulmonary RC-time is decreased in proximal CTEPH compared to IPAH, before and after PEA, which may be explained by increased wave reflection but also importantly by persistent structural changes after removal of proximal obstructions. A reduced RC-time in CTEPH is in accord with a wider pulse pressure and hence greater RV work for a given mean PA pressure.JOURNAL ARTICLESCOPUS: ar.jinfo:eu-repo/semantics/publishe
Morphological and geological features of Drake Passage, Antarctica, from anew digital bathymetric model
No full textThe Drake Passage is an oceanic gateway of about 850 km width located between South America and the Antarctic Peninsula that connects the southeastern Pacific Ocean with the southwestern Atlantic Ocean. It is an important gateway for mantle flow, oceanographic water masses, and migrations of biota. This sector developed within the framework of the geodynamic evolution of the Scotia Arc, including continental fragmentation processes and oceanic crust creation, since the oblique divergence of the South American plate to the north and the Antarctic plate to the south started in the Eocene. As a consequence of its complex tectonic evolution and subsequent submarine processes, as sedimentary infill and erosion mainly controlled by bottom currents and active tectonics, this region shows a varied physiography. We present a detailed map of the bathymetry and geological setting of the Drake Passage that is mainly founded on a new compilation of precise multibeam bathymetric data obtained on 120 cruises between 1992 and 2015, resulting in a new Digital Bathymetric Model with 200 × 200 m cell spacing. The map covers an area of 1,465,000 km2 between parallels 52°S and 63°S and meridians 70°W and 50°W at scale 1:1,600,000 allowing the identification of the main seafloor features. In addition, the map includes useful geological information related to magnetism, seismicity and tectonics. This work constitutes an international cooperative effort and is part of the International Bathymetric Chart of the Southern Ocean project, under the Scientific Committee on Antarctic Research umbrella. © 2018, © 2018 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group on behalf of Journal of Map.This work was supported through projects CTM2014-60451-C2-02/01, CTM2017-89711-C2-2/1-P and special action CTM2011-13970-E from ?Ministerio de Ciencia, Innovaci?n y Universidades? of Spain. This study is part of the British Antarctic Survey Polar Science for Planet Earth Programme funded by the Natural Environment Research Council. This work was also supported by the Scientific Committee on Antarctic Research. We thank to the crew and technicians of the RRS James Clark Ross, BIO Hesp?rides, RV Polarstern, RVIB Nathaniel B. Palmer, and the RV Araon and RV Onnuri for their support and cooperation in obtaining these data under sometimes severe sea conditions. The Scientific Committee on Antarctic Research (SCAR) is acknowledged for providing the framework that allowed this broad international venture. The production of the map was supported by SCAR
Primed T Cell Responses to Chemokines Are Regulated by the Immunoglobulin-Like Molecule CD31
No full textPMCID: PMC3378580This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Author Correction: A global analysis of terrestrial plant litter dynamics in non-perennial waterways
No full text© 2018 The Author(s) In the version of this Article originally published, the affiliation for M. I. Arce was incorrect; it should have been:5Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB), Berlin, Germany. This has now been corrected in the online versions of the Article
Eddy-induced variability in Southern Ocean abyssal mixing on climatic timescales
No full textPublishedJournal ArticleThis is the author accepted manuscript. The final version is available from Nature Publishing Group via the DOI in this record.The Southern Ocean plays a pivotal role in the global ocean circulation and climate. There, the deep water masses of the world ocean upwell to the surface and subsequently sink to intermediate and abyssal depths, forming two overturning cells that exchange substantial quantities of heat and carbon with the atmosphere. The sensitivity of the upper cell to climatic changes in forcing is relatively well established. However, little is known about how the lower cell responds, and in particular whether small-scale mixing in the abyssal Southern Ocean, an important controlling process of the lower cell, is influenced by atmospheric forcing. Here, we present observational evidence that relates changes in abyssal mixing to oceanic eddy variability on timescales of months to decades. Observational estimates of mixing rates, obtained along a repeat hydrographic transect across Drake Passage, are shown to be dependent on local oceanic eddy energy, derived from moored current meter and altimetric measurements. As the intensity of the regional eddy field is regulated by the Southern Hemisphere westerly winds, our findings suggest that Southern Ocean abyssal mixing and overturning are sensitive to climatic perturbations in wind forcing. © 2014 Macmillan Publishers Limited.The DIMES experiment is supported by the Natural Environment Research Council (NERC) of the UK and the US National Science Foundation. K.L.S. is supported by NERC. We are grateful to J. Ledwell, A. Bogdanoff, P. Courtois, K. Decoteau, D. Evans and X. Liang for their help in data collection and acknowledge the valuable assistance and hard work of the crew and technicians on the RRS James Cook, the RRS James Clark Ross and the RV Thomas G. Thompson. We also thank A. Thompson who provided many helpful comments, and E. Murowinski, R. Lueck and F. Wolk from Rockland Scientific for their support in microstructure data analysis
Exceptionally warm and prolonged flow of warm deep water toward the Filchner-Ronne Ice Shelf in 2017
No full text© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Ryan, S., Hellmer, H. H., Janout, M., Darelius, E., Vignes, L., & Schroeder, M. Exceptionally warm and prolonged flow of warm deep water toward the Filchner-Ronne Ice Shelf in 2017. Geophysical Research Letters, 47(13),(2020): e2020GL088119, doi:10.1029/2020GL088119.The Filchner‐Ronne Ice Shelf, fringing the southern Weddell Sea, is Antarctica's second largest ice shelf. At present, basal melt rates are low due to active dense water formation; however, model projections suggest a drastic increase in the future due to enhanced inflow of open‐ocean warm water. Mooring observations from 2014 to 2016 along the eastern flank of the Filchner Trough (76°S) revealed a distinct seasonal cycle with inflow if Warm Deep Water during summer and autumn. Here we present extended time series showing an exceptionally warm and long inflow in 2017, with maximum temperatures exceeding 0.5°C. Warm temperatures persisted throughout winter, associated with a fresh anomaly, which lead to a change in stratification over the shelf, favoring an earlier inflow in the following summer. We suggest that the fresh anomaly developed upstream after anomalous summer sea ice melting and contributed to a shoaling of the shelf break thermocline.The authors would like to express their gratitude to the officers and crews of RV Polarstern (cruises PS92 [Grant AWI_PS82_02], PS96 [Grant AWI_PS96_01], and PS111 [Grant AWI_PS111_01]), RRS Ernest Shackleton (Cruise ES060), and RSS James Clark Ross (Cruise JR16004) for their efficient assistance. E. D. received funding from the project TOBACO (267660), POLARPROG, Norges Forskningsrd
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