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Dynamic behaviour of the West Antarctic ice sheet in the Amundsen Sea Embayment during the later quaternary climatic cycles, pliocene to quaternary palaeoceanography in the Southwest Pacific, and holocene climate history of Maxwell Bay, King George Island.

De satte seg nesten uvirkelige mål. De skulle erobre de siste uoppdagede steder på kloden. Kan deres egenskaper og lederstil fortelle oss hvorfor noen lyktes bedre enn andre? Nansen var først ute. Skituren over Grønland hadde gitt ham ukuelig vågemot: Nå var målet Nordpolen. Siden ville Amundsen samme vei. Britene festet blikket på Antarktis. Først Schackleton, så Scott. Fire menn med store drømmer, sterk vilje, kraftig ego. Som vi vet, skulle ekspedisjonene føre til triumf . og tragedie. I sin nye bok skildrer Ragnar Kvam jr. noen av polarhistoriens mest dramatiske kapitler. Han setter søkelyset på hvem de er, disse fire lederskikkelsene. Hva var det som drev dem? Hvordan ledet de sine menn? Kan deres egenskaper og lederstil fortelle oss hvorfor noen lyktes bedre enn andre? Gjennom fire fortellinger får leseren et fascinerende portrett av "de fire store", av deres evne til å skape motivasjon og lagånd, av deres psykiske utrustning og evne til å takle ekstreme situasjoner. Kvams mål er å kaste nytt lys over det som i siste instans virkelig bestemmer deres måte å lede på deres personlighet.

The termination of the last ice age (Termination 1; T1) is crucial for our understanding of global climate change and for the validation of climate models. There are still a number of open questions regarding for example the exact timing and the mechanisms involved in the initiation of deglaciation and the subsequent interhemispheric pattern of the warming. Our study is based on a well-dated and high-resolution alkenone-based sea surface temperature (SST) record from the SE-Pacific off southern Chile (Ocean Drilling Project Site 1233) showing that deglacial warming at the northern margin of the Antarctic Circumpolar Current system (ACC) began shortly after 19,000 years BP (19 kyr BP). The timing is largely consistent with Antarctic ice-core records but the initial warming in the SE-Pacific is more abrupt suggesting a direct and immediate response to the slowdown of the Atlantic thermohaline circulation through the bipolar seesaw mechanism. This response requires a rapid transfer of the Atlantic signal to the SE-Pacific without involving the thermal inertia of the Southern Ocean that may contribute to the substantially more gradual deglacial temperature rise seen in Antarctic ice-cores. A very plausible mechanism for this rapid transfer is a seesaw-induced change of the coupled ocean–atmosphere system of the ACC and the southern westerly wind belt. In addition, modelling results suggest that insolation changes and the deglacial CO2 rise induced a substantial SST increase at our site location but with a gradual warming structure. The similarity of the two-step rise in our proxy SSTs and CO2 over T1 strongly demands for a forcing mechanism influencing both, temperature and CO2. As SSTs at our coring site are particularly sensitive to latitudinal shifts of the ACC/southern westerly wind belt system, we conclude that such latitudinal shifts may substantially affect the upwelling of deepwater masses in the Southern Ocean and thus the release of CO2 to the atmosphere as suggested by the conceptual model of [Toggweiler, J.R., Rusell, J.L., Carson, S.R., 2006. Midlatitude westerlies, atmospheric CO2, and climate change during ice ages. Paleoceanography 21. doi:10.1029/2005PA001154].

The most frequent way of summarizing the story of the NBSX may be illustrated by the following few paragraphs. Shortly after the Second World War had ended Norway took a leading role in organising the first international expedition to Antarctica. Norway was in charge of meteorology and surveying, Great Britain was responsible for geology and Sweden was entrusted with glaciology. The British RAF assisted in air operations 1949/50 with five officers (in finding a landing place for the expedition as well as for meteorological investigations, one officer remained as radio operator), the Norwegian Wideröe Company assisted in 1950/51 (air surveying) and the Swedish Air Force in 1951/52, with 6 officers (originally for reconnaissance of ice conditions as well as being prepared for emptying the base). The Norwegian sealer Norsel landed the party and the whaler Thorshövdi assisted as well for transport of dogs aircraft and weasels. For general overviews and details of the scientific achievements, logistics and perspectives of international cooperation there are several works available.

As a result of intensive field activities carried out by several nations over the past 15 years, a set of accumulation measurements for western Dronning Maud Land, Antarctica, was collected, based on firn-core drilling and snow-pit sampling. This new information was supplemented by earlier data taken from the literature, resulting in 111 accumulation values. Using Geographical Information Systems software, a first region-wide mean annual snow-accumulation field was derived. In order to define suitable interpolation criteria, the accumulation records were analyzed with respect to their spatial autocorrelation and statistical properties. The resulting accumulation pattern resembles well- known characteristics such as a relatively wet coastal area with a sharp transition to the dry interior, but also reveals complex topographic effects. Furthermore, this work identifies new high-return shallowdrilling sites by uncovering areas of insufficient sampling density.

Siste halvdel av 1950-tallet var en viktig periode i norsk hvalfangst. Norge, som tidligere hadde vært den dominerende hvalfangstnasjonen, var som resultat av hard konkurranse kommet på defensiven i forhold til de andre hvalfangstnasjonene. Den høye hvaloljeprisen, som blant annet var forårsaket av Europas fettbehov i kjølvannet av den andre verdenskrig, resulterte i at nye nasjoner etter krigen engasjerte seg i hvalfangst. For å sikre seg en størst mulig andel av totalkvoten ønsket Sovjetunionen og Japan nå å foreta en kraftig utbygging av sine fangstflåter, noe som ville gjøre situasjonen enda vanskeligere for den norske hvalfangstnæringen. Det var av største viktighet at denne ekspansjonen ble stoppet, siden dette spørsmålet i norske hvalfangstkretser ble oppfattet som et være eller ikke være for norsk hvalfangst. De norske hvalfangstselskapene startet derfor en kampanje for å få regjeringen til å stanse de to landenes utbyggingsplaner. Mitt hovedfokus i denne oppgaven vil være å belyse hvalfangstnæringens rolle i utformingen av den norske hvalfangstpolitikken på 1950-tallet. For å kunne gi et svar på dette spørsmålet har jeg tatt for meg to av hvalfangstpolitikkens viktigste saker dette tiåret. Den første dreier seg om den nevnte kampen for å stanse Sovjetunionens og Japans ekspansjonsplaner, mens den andre dreier seg om kampen for en ordning med nasjonale kvoter. En studie av disse to sakene gir også innsyn i næringen som helhet. I tillegg til å kartlegge hvalfangstnæringens politiske innflytelse vil det også være viktig å gi en fremstilling av utviklingen innen hvalfangstreguleringen i denne perioden, altså siste halvdel av 1950-tallet. Med begrepet norsk hvalfangstpolitikk, mener jeg den politikken regjeringen utformet og som blant annet ble presentert på de årlige møtene i Den internasjonale hvalfangskommisjonen (IWC). For å kunne gi et godt svar på problemstillingen er det nødvendig å besvare flere underliggende spørsmål. Hvalfangstselskapene organiserte seg tidlig gjennom dannelsen av Norges Hvalfangstforbund. Dette var en organisasjon som kjempet for at hvalfangstredernes interesser ble ivaretatt. Hvalfangstrederne var i tillegg representert i Hvalrådet. Dette var et statlig organ som hadde en rådgivende funksjon i regjeringens utarbeidelse av den norske hvalfangstpolitikken. Følgende spørsmål blir derfor viktige i mitt arbeid: Hvilken rolle spilte Norges Hvalfangstforbund i utformingen av den norske hvalfangstpolitikken? Hvordan opererte næringens representanter for å få gjennomslag for sine interesser i Hvalrådet? Det vil også være nødvendig å kartlegge sammenhengen mellom Hvalrådet og regjeringen. I hvilken grad var Hvalrådets uttalelser utslagsgivende for den endelige norske hvalfangstpolitikken? Bortsett fra tiden da Norge stod utenfor Den internasjonale hvalfangstkonvensjonen, sendte landet hvert år en delegasjon til kommisjonens årlige møter. Det vil være viktig å undersøke i hvilken grad næringen var representert i disse delegasjonene. Møtte den norske delegasjonen med bundet mandat, eller hadde den en viss frihet til å forhandle? Mot slutten av oppgaven ønsker jeg å se komparativt på hvalfangstnæringens politiske innflytelse i forhold til landbruket og fiskerinæringen i den samme perioden. Oppnådde hvalfangstnæringen større politisk innflytelse sammenliknet med disse næringene, og hva skyldtes i tilfelle dette?

Macrobenthic soft-bottom molluscs were sampled in 30 stations located in the Bellingshausen Sea at depths ranging from 90 to 3304 m. The samples were collected using a quantitative grab box-corer during the cruises BENTART 03, from 24 January to 3 March 2003, and BENTART 06, from 2 January to 16 February 2006. Molluscs represent 1074 specimens belonging to 62 species of Polyplacophora, Gastropoda, Bivalvia and Scaphopoda. The bivalve Cyamiocardium denticulatum was the most abundant species (448 specimens). The abundance per station varied between 1 and 446 specimens. The Shannon–Wiener diversity index ranged between one specimen and 2.36, the Pielou evenness index ranged between 0.00 and 1 and species richness ranged from 1 to 14 species. Diversity showed great variations at different stations. After multivariate analysis (cluster analysis and nonmetrical multidimensional scaling) based on Bray–Curtis similarities, we were able to separate two principal clusters. The first cluster groups together species from shallower bottoms near Peter I Island and the Antarctic Peninsula, and the second cluster groups together species from deeper bottoms in the Bellingshausen Sea. The combination of environmental variables with the highest correlations with faunistic data was that of depth and coarse sand at the surface.

This review concerns crustaceans that associate with sea ice. Particular emphasis is placed on comparing and contrasting the Arctic and Antarctic sea ice habitats, and the subsequent influence of these environments on the life history strategies of the crustacean fauna. Sea ice is the dominant feature of both polar marine ecosystems, playing a central role in physical processes and providing an essential habitat for organisms ranging in size from viruses to whales. Similarities between the Arctic and Antarctic marine ecosystems include variable cover of sea ice over an annual cycle, a light regimen that can extend from months of total darkness to months of continuous light and a pronounced seasonality in primary production. Although there are many similarities, there are also major differences between the two regions: The Antarctic experiences greater seasonal change in its sea ice extent, much of the ice is over very deep water and more than 80% breaks out each year. In contrast, Arctic sea ice often covers comparatively shallow water, doubles in its extent on an annual cycle and the ice may persist for several decades. Crustaceans, particularly copepods and amphipods, are abundant in the sea ice zone at both poles, either living within the brine channel system of the ice‐crystal matrix or inhabiting the ice–water interface. Many species associate with ice for only a part of their life cycle, while others appear entirely dependent upon it for reproduction and development. Although similarities exist between the two faunas, many differences are emerging. Most notable are the much higher abundance and biomass of Antarctic copepods, the dominance of the Antarctic sea ice copepod fauna by calanoids, the high euphausiid biomass in Southern Ocean waters and the lack of any species that appear fully dependent on the ice. In the Arctic, the ice‐associated fauna is dominated by amphipods. Calanoid copepods are not tightly associated with the ice, while harpacticoids and cyclopoids are abundant. Euphausiids are nearly absent from the high Arctic. Life history strategies are variable, although reproductive cycles and life spans are generally longer than those for temperate congeners. Species at both poles tend to be opportunistic feeders and periods of diapause or other reductions in metabolic expenditure are not uncommon.