TEMPURA: TEMPeratUre Reconstruction At
past rapid climate transitions

TEMPURA proposal is aimed to quantify the temperature change in past rapid climate events in Iberia, focusing on those transitions that represent a large temperature change (above 2°C) in a short time period (decades-centuries) during
glacial terminations and during the Holocene. We are going to apply for the first time in Iberia Peninsula a combination of novel geochemical quantitative proxies in speleothems and lake sediments that, after a robust calibration, will produce temperature estimations for past abrupt changes.

Those indicators are:
(i) the isotopic composition of fluid inclusions,
(ii) the clumped isotopes and
(iii) the composition in branched- glycerol dialkyl glycerol tetraethers (branched-GDGTs).

We are looking for a researcher that brings oceanographic expertise to the application and analysis of the Norwegian Earth System Model (NorESM) in close collaboration with a wide range of earth system modellers at NORCE and the Bjerknes Centre for Climate Research (BCCR) and the national NorESM consortium. The successful candidate is expected to contribute with modelling expertise to a vibrant national paleoclimatic community as well as develop a relevant research agenda.

We offer an exciting job opportunity in the field of global ocean and earth system modelling. The position is full time and permanent, and initially funded for 2 years, primarily through the Research Council of Norway project ABRUPT Arctic Climate Change. By combining reconstructions of Dansgaard-Oeschger (DO) events occurring in the 30-40 ka time interval with multi-model simulations, ABRUPT will chart the distribution of sea ice and ocean states in the Nordic Seas during past abrupt changes to further our understanding of these enigmatic large scale climate shifts. This includes exploring how they might be relevant for future Arctic change.

Smaller involvement in other ongoing projects, with similar competence required, must be expected. The successful candidate is expected to attract own funding through externally funded projects to support his/her position as well as bringing in new junior positions such as PhD students or postdocs. NORCE provides technical support to train its employees to develop and write competitive research proposals.

MARUM is currently searching a highly motivated and excellently qualified postdoctoral scientist with a recent PhD degree and research experience in marine geochemistry and stratigraphy working with scientific ocean drilling data for a project entitled "In2Cretaceous – evaluating the potential of equatorial Pacific Shatsky Rise sedimentary deposits for extending high resolution paleoceanographic reconstructions from the Maastrichtian into the Campanian (72 to 84 Ma)". The project will be conducted within the Priority Programme SPP527 "International Ocean Discovery Program" (IODP) framework of the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation).

Applications are invited for the Arnell Post-Doctoral Research Associate position for a fixed-term of 24 months to work on a project funded by Downing College and in collaboration with the Centre for Climate Repair. The post holder will be based at the Department of Geography and will work under the guidance of Dr Francesco Muschitiello and Dr Matthew Osman.

Searching for a postdoc candidate, ideally an expert in paleoclimatology and statistics to perform statistical reconstructions of regional to global climate variability from paleo-proxy evidence on centennial to millennial timescales. Together, with project partners from the University of Tübingen, you will perform a global characterization of the spectrum of climate variability across spatial scales and climate states from proxy data and PalMod simulations. You will be associated with the AWI research team Earth System Diagnostics (https://www.awi.de/en/science/geosciences/polar-terrestrial-environmental-systems/research-foci/earth-system-diagnostics.html) working on ice-cores, tree rings, corals, sediment cores as well as statistical climate models and proxy forward models.

Small-scale mixing in the ocean interior affects the large-scale global meridional overturning circulation (MOC) and tracer distributions. However, little is known about how and why mixing has changed in the past, nor what the effects of those changes were on circulation, climate and biogeochemical cycles. This project will examine ocean mixing in the modern and last glacial maximum (LGM) ocean using a combination of numerical modeling and existing observations. In the past, only mixing near sources of turbulence have been considered (near-field effects), but mixing more distant from turbulence sources, carried away by internal waves or wave/current/eddy interactions (far field effects) are now possible to include. New parameterization concepts of diapycnal mixing will be explored in the global coarse-resolution ocean component of an intermediate complexity climate model. Parameterizations of mesoscale eddies will also be evaluated. The model will be calibrated for the modern ocean with modern observations including physical and biogeochemical tracer distributions, and microstructure-based diffusivity estimates. Subsequently, it will be applied to the glacial ocean in a suite of experiments that cover uncertainties in forcing, circulation state and tidal energy input to the internal wave field. Glacial sediment data will be used to evaluate the model simulations and test hypotheses regarding effects of stratification, circulation geometry and tides on diapycnal mixing and effects of southern hemisphere wind changes on the carbon cycle and atmospheric carbon dioxide. The project would improve modeling of paleoclimate and future climate, and foster collaborations between physical oceanographers and paleoceanographers. New model code with user guide and documentation will be posted online with a webinar on model use provided. The project will support an early career post-doctoral investigator and a student. Personnel will be involved in outreach activities at a local museum and in public discussion forums.

Mixing and the meridional overturning circulation during the last glacial period remain controversial. Shoaling of the interface between North Atlantic Deep Water and Antarctic Bottom Water and increased stratification are two mechanisms that have been suggested to reduce diapycnal mixing. On the other hand, a shift of tidal energy input from the continental shelves to the deep ocean due to sea level lowering has been hypothesized to increase diapycnal mixing. A parameterization of far field mixing effects will be incorporated into the Oregon State University (OSU) version of the intermediate-complexity University of Victoria (UVic) global climate model. Tuning to modern ocean conditions using modern observations followed by assessment of LGM performance using available paleo observations will permit the examination of these science goals: to investigate how diapycnal mixing in the LGM compares to modern magnitudes; how potential differences may have affected the LGM MOC; and what the consequences of such effects would have been for the global carbon cycle. The parameterizations representing far field effects, tested and tuned in the OSU-UVic model, will also be ported to the newest version of the Modular Ocean Model (MOM6) of the Community Earth System Model (CESM), though extensive tuning, testing and evaluation with CESM is not planned. Abstract at NSF.

We are seeking a Post Doctoral Researcher to work on a Science Foundation Ireland funded project (PCARB: Investigating the past climate influence on the carbon accumulation rates of Irish blanket bogs). This project aims to assess how past changes in climate altered carbon accumulation in Irish blanket bogs, to inform estimates of potential future carbon sequestration. The PCARB team will consist of the P.I. (Dr Lisa Orme), a PhD student researching Holocene variability in carbon accumulation rates (Work Package 1) and the advertised postdoctoral researcher, who will lead Work Packages 2 and 3. Work Package 2 is an extensive assessment of carbon accumulation rates during the last millennium from sites across Ireland. The developed palaeo-environmental dataset, in combination with modelling of future blanket bog extent, will inform estimates of the likely future carbon accumulation by blanket bogs in Ireland (Work Package 3).