«Changing Polar Regions 25th International Congress on Polar Research March 17-22, 2013, Hamburg, Germany German Society for Polar Research Edited by ...»
"Changing Polar Regions" - 25th International Congress on Polar Research 2013 THE FUTURE OF POLAR SCIENCE
The International Polar Year has been a great boost to polar science. International coordination, collection of valuable data sets, intensified outreach to the public and education has created increased awareness for polar issues in society. A major new development of the IPY is the inclusion of the Humanities. Efforts are now underway to maintain the high level of polar research as we are all aware that climate change will affect the high North and parts of Antarctica more severely than the rest of the world. In many countries strategic plans for polar science are being developed and SCAR initiates a “Horizon Scan Activity” to capture the vision for future polar science.
In Germany the Ministry for Science and Education (BMBF) jointly with the German SCAR/IASC Committee published a strategic plan for Arctic research focusing on 6 major topics. Antarctic research in Germany is so far only supported via the German Science Foundation (DFG) and the AWI, but should also be underpinned by an Antarctic science strategy. Ideally, a new Polar Research Strategy of the German Government should be developed encompassing the bipolar approach of German polar science.
A way into the future of polar science should focus on some new aspects: a) Natural science and humanities need to collaborate on an equal footing as the research questions gain more and more socio-economic relevance. Fields of science outside the ‘normal’ polar science need to be explored. b) Observations of both Polar Regions have to be improved by new technologies in order to provide much needed data for model development. It should include year round, automated observations in the sea and on the ground to complement satellite measurements. These data need to be easily accessible. c) International coordination of polar infrastructure is required to improve access to the remote Polar Regions for all scientists and to use the available infrastructure most effectively. It is suggested that this is a task for the Horizon 2020 programme of the EU.
"Changing Polar Regions" - 25th International Congress on Polar Research 2013 FROM BASIN TO MOUNTAINS: THE UPLIFT OF THE SHACKLETON RANGE
The Shackleton Range is situated between 80° – 81°S and 19° – 31°W where it forms the continuation of the Transantarctic Mountains to the Weddell Sea sector.
Regional geological architecture comprises Precambrian igneous and (meta-) sedimentary rocks of an Early Paleozoic nappe stack and post-orogenic red beds.
The nappe stacking was a consequence of the collision of East and West Gondwana.
The uplift and exhumation history of the Shackleton Range has been analysed via thermochronological methods, especially fission track analysis. Fission track data refer to cooling temperatures of 230° – 350°C (zircons) and 60° – 110°C (apatites), respectively. Zircon ages from vertical sample profiles in the Shackleton Range vary between ~160 to 210 Ma, while apatite ages range from ~95 to ~170 Ma (Schäfer, 1998; Lisker et al., 1999). Originally, these data and associated proxies have been interpreted qualitatively in terms of two cooling/ exhumation stages during Jurassic and mid-Cretaceous times.
However, the recognition of volcanoclastic rocks associated with the ~180 Ma Ferrar event in the vicinity of the sample locations (Buggisch et al., 1994) challenges this exhumation concept. The superficial position of these sediments in Jurassic times and the accumulation of much younger fission track ages is in rigorous contradiction within a continuous cooling concept.
New fission track proxy data and first apatite (U-Th-Sm)/He ages (referring to cooling to temperatures of 40° – 80°C) were generated within DFG grant LI 745/15-1 to develop a new exhumation scenario. (U-Th-Sm)/He ages of 88 – 171 Ma are only little younger than fission track ages of the same samples. Tentative thermal history modelling of the combined thermochronological data suggests early Mesozoic cooling followed by (post) Jurassic re-heating. Final cooling to surface temperatures occurred since the Late Cretaceous. This scenario requires burial of the Shackleton Range region, and thus the existence of a sedimentary basin. Subsequent basin inversion then triggered isostatic compensation associated with uplift. The thickness of the now vanished sedimentary strata did unlikely exceed 2 – 3 km. Future work includes additional apatite fission track analyses to quantify geometry, depth and timing of this depocentre and the evaluation of potential links with the coeval basin (system) along the Transantarctic Mountains and/ or similar settings in Dronning Maud Land (e.g., the Heimefrontfjella).
"Changing Polar Regions" - 25th International Congress on Polar Research 2013 ADOLPH ERMAN UND SEIN BEITRAG ZUR ERFORSCHUNG DES
ERDMAGNETISMUS DER ERDE
Adolph Erman (1806–1877), der in den Jahren 1828–1830 eine Umsegelung der Welt unternommen hatte, ist heute wenig bekannt. Seine wissenschaftliche Tätigkeit war in großem Maße mit Russland verbunden. Die von ihm gesammelten Angaben über den Geomagnetismus, die Geologie, die Geografie und die Meteorologie OstSibiriens sowie seine ethnografischen Untersuchungen wurden seinerzeit zum wichtigsten Grundlagenmaterial über die Naturverhältnisse und das Leben der Menschen in Ost-Sibirien. Die größte Bedeutung für die Russlandkunde hatten jedoch Ermans astronomische Ortsbestimmungen an vielen Punkten Sibiriens, die wesentlich zu einer ersten genauen Kartographie Sibiriens beitrugen.
Während seiner Weltreise hatte Erman an insgesamt 350 Punkten nicht nur die Abweichung und Neigung, sondern auch die Intensität der magnetischen Kraft gemessen. Diese Angaben wurden in der Folgezeit häufig genutzt und von vielen Wissenschaftlern wie z. B. Carl Friedrich Gauss (für seine Theorie des Erdmagnetismus), Edward Sabine und Christopher Hansteen hoch geschätzt.
Heinrich Berghaus und Alexander von Humboldt verwendeten Ermans geomagnetischen Beobachtungen auf ihren Kartendarstellungen. In der zweiten Auflage des „Berghaus' Physikalischen Atlasses“ hatte Erman eine vollständige Karte der Deklinationsbeobachtungen aus den Jahren 1827 bis 1831 zusammengestellt.
Seine Angaben fanden auch Eingang in die Atlas-Karten über Meeresströmungen und die magnetische Intensität. In den 1860er Jahren reduzierten Erman zusammen mit dem englischen Wissenschaftler Heinrich Petersen nach der Gauss'schen Theorie des Erdmagnetismus mittels der angenommenen Säkular-Änderung alle bis 1870 vorhandenen magnetischen Beobachtungen auf 1829 und berechneten nun auf 10 Breitenparallele gleichweit voneinander abstehende Meridianpunkte. Diese Angaben wurden im Jahre 1874 im Werk "Die Grundlagen der Gaussischen Theorie und die Erscheinungen des Erdmagnetismus im Jahre 1829" publiziert und im Jahre 1891 vom Direktor der Seewarte in Hamburg, Georg Neumayer, in der IV. Abteilung des "Berghaus' Physikalischer Atlasses" unter dem Titel "Atlas des Erdmagnetismus" auf die Karte übertragen.
Im Vortrag soll gezeigt werden, warum Ermans Name in Vergessenheit geraten ist.
"Changing Polar Regions" - 25th International Congress on Polar Research 2013 WHERE ARE RELATIVES OF TINY DEEP-SEA ANTARCTIC ISOPOD
MICROCOPE DENTICULATE FROM?
The genus of deep-sea minute isopods of the family Munnopsidae, Microcope Malyutina, 2008 is an example of taxa with not clear taxonomic position into the family and interesting distribution. It was described for three species: two new species from the Southern Ocean and southern Atlantic and known species, Eurycope ovatum Birstein, 1970 from the north-western Pacific. The genus is considered as an intermediate between three subfamilies of Munnopsidae as it combines characters common for some genera of Eurycopinae, Betamorphinae and Syneurycopinae, but cannot be related to any known genus of the existing subfamilies. Microcope species can be distingueshed by minute seed-like broad oval body with fused pereonites 5–7, the short, not visible head hidden under the anterior flange of pereonite 1, with narrow mouthfield protruded ventrally.
Microcope denticulate Malyutina, 2008 from the Scotia and Bellingshausen seas, another southern Atlantic species, M. levissima Malyutina, 2008 from the Cape Basin and M. ovata (Birstein, 1970) from the Kurile-Kamchatka Trench were recorded mainly from abyssal depths down to 5054 m. Recently a new species of Microcope was found from the Chatham Rise near the New Zealand on a shelf depths around 300 m. This finding extended the range of geographical and vertical distribution of the genus, making this group even more interesting for future phylogenetic analysis.
"Changing Polar Regions" - 25th International Congress on Polar Research 2013 THE DFG PRIORITY PROGRAM 1158 "ANTARCTIC RESEARCH
WITH COMPARATIVE INVESTIGATIONS IN GLACIATED AREAS OFTHE ARCTIC"
Since more than 30 years the German Research Foundation (DFG) provides substantial funding of polar research in coordinated and priority programs (Schwerpunktprogramm, SPP), starting with Antarctica and later expanded to the Arctic. Major motivation for this coordinated funding is to support German scientists to use a variety of polar research platforms, such as the RV “Polarstern”, polar research stations, or polar planes, provided by the Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung (AWI) in Bremerhaven and the Federal Institute for Geosciences and National Resources (Bundesanstalt für Geowissenschaften und Rohstoffe, BGR) in Hannover.
In 2012, the DFG Priority Program 1158 (Antarctic research with comparative investigations in glaciated areas of the Arctic) was extended by 6 years (for the period 2013 - 2018). For this funding phase, the SPP has reduced and reoriented its major research topics. The topics no longer are disciplinary in nature. Instead, they aim on providing important contributions to the role of Antarctica in the Earth System by focusing on the four overarching, interdisciplinary research topics “Development of the Continent“, “Gateways to Lower Latitudes”, “Dynamics of Climate Sys-tem Components”, and Response to Environmental Change”.
This talk provides an introduction into the SPP 1158, with its importance for German polar research and its development during the past years. The talk introduces a total of 18 succeeding scientific talks, in which significant findings concerning our interdisciplinary research topics, funded by the SPP, are presented in four scientific sessions on Tuesday afternoon and Wednesday morning. These presentations function as a public Report Colloquium of the SPP, but also intent to present and discuss major scientific results with polar researchers and interested scientists not involved in the SPP.
"Changing Polar Regions" - 25th International Congress on Polar Research 2013 SOUNDSCAPES OF THE SOUTHERN OCEAN: PASSIVE ACOUSTIC
MONITORING IN THE WEDDELL SEA
The Southern Ocean provides an important habitat for marine mammals, both residential and migratory, yet long term studies of their habitat usage are hampered by the region’s seasonal inaccessibility. To overcome this problem, two autonomous underwater passive acoustic recorders were deployed in the Weddell Sea in 2008 to collect multiyear passive acoustic data. The recorders were retrieved in 2010 and the acoustic recordings were analyzed in terms of broad- and narrow-band noise. Noise in this context is defined as the acoustic energy not assignable to a specific singular source. It comprises both biotic as well as abiotic components. Noise levels were determined by selecting the quietest 10 s of each 5 min recording to exclude energetic contributions from nearby singular acoustic sources. The respective sound pressure levels (SPL) and spectra were correlated with time series of environmental covariates.
The ambient noise levels of both recorders were found to be highly variable in time, ranging from 102 to 115 dB re 1 μPa (broadband SPL 5th and 95th percentile), and were correlated with the sea ice cover and wind speed. The annual variation of the ice cover caused a bimodal distribution of broadband SPL. In winter the SPL mode was 106 dB re 1 μPa. By contrast, storms over the open ocean in summer resulted in an SPL mode of 111 dB dB re 1 μPa. Variation in the ambient noise spectra could be correlated to wind speed and ice coverage. The acoustic presence of several mysticete (Antarctic blue whale, Balaenoptera musculus intermedia, fin whale, Balaenoptera physalus) and pinniped (leopard seal, Hydrurga leptonyx, crabeater seal, Lobodon carcinophaga) species created distinct bands in the spectra that contributed considerably to ambient noise levels. Comparison of the timing of these noise bands between the two acoustic data sets revealed offsets in the occurrence of acoustic activity between both recorders, suggestive of marine mammal latitudinal migration. At 66°S (the northern recorder position) fin whales were acoustically present earlier and longer in summer than at 69°S. Similarly, the blue whale chorus was more intense at 66°S than at 69°S. This might be related to the response of these species to the seasonal variation in the extension and density of sea ice.
Seasonal cycles were also detected in the noise band attributed to crabeater seal vocalisations. They were annually present in September and November, followed by the leopard seals noise band, which is discernible between December and January.
Results from this latitudinal recorder pair give a first impression on possible marine mammal migration patterns as well as the spatial and temporal distribution of marine "Changing Polar Regions" - 25th International Congress on Polar Research 2013 mammal acoustic presence in the Southern Ocean. Additional recorders deployed in the basin wide HAFOS array will expand the spatial and temporal resolution of the acoustic dataset and allow conducting detailed multiyear studies of marine mammal acoustic presence and behavior throughout the Weddell Sea.
"Changing Polar Regions" - 25th International Congress on Polar Research 2013 THE KOHNEN LINEAMENT – A PROMINENT MAGNETIC ANOMALY