polar ice cores; climate dynamics and modelling; paleoclimate; groundwater; stable isotopes in the environment; water cycle; greenhouse gases; radionuclides
Stocker Benjamin David, Yu Zicheng, Massa Charly, Joos Fortunat (2017), Holocene peatland and ice-core data constraints on the timing and magnitude of CO 2 emissions from past land use, in Proceedings of the National Academy of Sciences
, 114(7), 1492-1497.
Battaglia Gianna, Steinacher Marco, Joos Fortunat (2016), A probabilistic assessment of calcium carbonate export and dissolution in the modern ocean, in Biogeosciences
, 13(9), 2823-2848.
Neff Basil, Born Andreas, Stocker Thomas F. (2016), An ice sheet model of reduced complexity for paleoclimate studies, in Earth System Dynamics
, 7(2), 397-418.
Legrand Michel, McConnell Joseph, Fischer Hubertus, Wolff Eric W., Preunkert Susanne, Arienzo Monica, Chellman Nathan, Leuenberger Daiana, Maselli Olivia, Place Philip, Sigl Michael, Schüpbach Simon, Flannigan Mike (2016), Boreal fire records in Northern Hemisphere ice cores: a review, in Climate of the Past
, 12(10), 2033-2059.
Brovkin Victor, Brücher Tim, Kleinen Thomas, Zaehle Sönke, Joos Fortunat, Roth Raphael, Spahni Renato, Schmitt Jochen, Fischer Hubertus, Leuenberger Markus, Stone Emma J., Ridgwell Andy, Chappellaz Jérôme, Kehrwald Natalie, Barbante Carlo, Blunier Thomas, Dahl Jensen Dorthe (2016), Comparative carbon cycle dynamics of the present and last interglacial, in Quaternary Science Reviews
, 137, 15-32.
Clark Peter U., Shakun Jeremy D., Marcott Shaun A., Mix Alan C., Eby Michael, Kulp Scott, Levermann Anders, Milne Glenn A., Pfister Patrik L., Santer Benjamin D., Schrag Daniel P., Solomon Susan, Stocker Thomas F., Strauss Benjamin H., Weaver Andrew J., Winkelmann Ricarda, Archer David, Bard Edouard, Goldner Aaron, Lambeck Kurt, Pierrehumbert Raymond T., Plattner Gian-Kasper (2016), Consequences of twenty-first-century policy for multi-millennial climate and sea-level change, in Nature Climate Change
, 6(4), 360-369.
Pfister Patrik L, Stocker Thomas F (2016), Earth system commitments due to delayed mitigation, in Environmental Research Letters
, 11(1), 014010-014010.
Eggleston S., Schmitt J., Bereiter B., Schneider R., Fischer H. (2016), Evolution of the stable carbon isotope composition of atmospheric CO2 over the last glacial cycle, in Paleoceanography
, 31(3), 434-452.
Landais Amaelle, Masson-Delmotte Valérie, Capron Emilie, Langebroek Petra M., Bakker Pepijn, Stone Emma J., Merz Niklaus, Raible Christoph C., Fischer Hubertus, Orsi Anaïs, Prié Frédéric, Vinther Bo, Dahl-Jensen Dorthe (2016), How warm was Greenland during the last interglacial period?, in Climate of the Past
, 12(9), 1933-1948.
Magnan Alexandre K., Colombier Michel, Billé Raphaël, Joos Fortunat, Hoegh-Guldberg Ove, Pörtner Hans-Otto, Waisman Henri, Spencer Thomas, Gattuso Jean-Pierre (2016), Implications of the Paris agreement for the ocean, in Nature Climate Change
, 6(8), 732-735.
Chikamoto Megumi O., Timmermann Axel, Yoshimori Masakazu, Lehner Flavio, Laurian Audine, Abe-Ouchi Ayako, Mouchet Anne, Joos Fortunat, Raible Christoph C., Cobb Kim M. (2016), Intensification of tropical Pacific biological productivity due to volcanic eruptions, in Geophysical Research Letters
, 43(3), 1184-1192.
Lionello Piero, Trigo Isabel F., Gil Victoria, Liberato Margarida L. R., Nissen Katrin M., Pinto Joaquim G., Raible Christoph C., Reale Marco, Tanzarella Annalisa, Trigo Ricardo M., Ulbrich Sven, Ulbrich Uwe (2016), Objective climatology of cyclones in the Mediterranean region: a consensus view among methods with different system identification and tracking criteria, in Tellus A: Dynamic Meteorology and Oceanography
, 68(1), 29391-29391.
Ruosch Melanie, Spahni Renato, Joos Fortunat, Henne Paul D., van der Knaap Willem O., Tinner Willy (2016), Past and future evolution of Abies alba forests in Europe - comparison of a dynamic vegetation model with palaeo data and observations, in Global Change Biology
, 22(2), 727-740.
Muthers Stefan, Raible Christoph C., Rozanov Eugene, Stocker Thomas F. (2016), Response of the AMOC to reduced solar radiation; the modulating role of atmospheric chemistry, in Earth System Dynamics
, 7(4), 877-892.
Keel Sonja G., Joos Fortunat, Spahni Renato, Saurer Matthias, Weigt Rosemarie B., Klesse Stefan (2016), Simulating oxygen isotope ratios in tree ring cellulose using a dynamic global vegetation model, in Biogeosciences
, 13(13), 3869-3886.
Camenisch Chantal, Keller Kathrin M., Salvisberg Melanie, Amann Benjamin, Bauch Martin, Blumer Sandro, Brázdil Rudolf, Brönnimann Stefan, Büntgen Ulf, Campbell Bruce M. S., Fernández-Donado Laura, Fleitmann Dominik, Glaser Rüdiger, González-Rouco Fidel, Grosjean Martin, Hoffmann Richard C., Huhtamaa Heli, Joos Fortunat, Kiss Andrea, Kotyza Oldřich, Lehner Flavio, Luterbacher Jürg, Maughan Nicolas, Neukom Raphael, et al. (2016), The 1430s: a cold period of extraordinary internal climate variability during the early Spörer Minimum with social and economic impacts in north-western and central Europe, in Climate of the Past
, 12(11), 2107-2126.
Saunois Marielle, Bousquet Philippe, Poulter Ben, Peregon Anna, Ciais Philippe, Canadell Josep G., Dlugokencky Edward J., Etiope Giuseppe, Bastviken David, Houweling Sander, Janssens-Maenhout Greet, Tubiello Francesco N., Castaldi Simona, Jackson Robert B., Alexe Mihai, Arora Vivek K., Beerling David J., Bergamaschi Peter, Blake Donald R., Brailsford Gordon, Brovkin Victor, Bruhwiler Lori, Crevoisier Cyril, Crill Patrick, et al. (2016), The global methane budget 2000–2012, in Earth System Science Data
, 8(2), 697-751.
Steinacher M., Joos F. (2016), Transient Earth system responses to cumulative carbon dioxide emissions: linearities, uncertainties, and probabilities in an observation-constrained model ensemble, in Biogeosciences
, 13(4), 1071-1103.
Gerber C., Vaikmäe R., Aeschbach W., Babre A., Jiang W., Leuenberger M., Lu Z.-T., Mokrik R., Müller P., Raidla V., Saks T., Waber H. N., Weissbach T., Zappala J. C., Purtschert R. (2016), Transport of salt and freshwater in the Atlantic Subpolar Gyre, in Geochimica et Cosmochimica Acta
, 205, 187-210.
Merz Niklaus, Born Andreas, Raible Christoph C., Stocker Thomas F. (2016), Warm Greenland during the last interglacial: the role of regional changes in sea ice cover, in Climate of the Past
, 12(10), 2011-2031.
Howes Ella L., Joos Fortunat, Eakin C. Mark, Gattuso Jean-Pierre (2015), An updated synthesis of the observed and projected impacts of climate change on the chemical, physical and biological processes in the oceans, in Frontiers in Marine Science
, 2, 1-27.
Oyabu Ikumi, Iizuka Yoshinori, Fischer Hubertus, Schüpbach Simon, Gfeller Gideon, Svensson Anders, Fukui Manabu, Steffensen Jørgen Peder, Hansson Margareta (2015), Chemical compositions of solid particles present in the Greenland NEEM ice core over the last 110,000 years, in Journal of Geophysical Research: Atmospheres
, 120(18), 9789-9813.
Allin S. J., Laube J. C., Witrant E., Kaiser J., McKenna E., Dennis P., Mulvaney R., Capron E., Martinerie P., Roeckmann T., Blunier T., Schwander J., Fraser P. J., Langenfelds R. L., Sturges W. T. (2015), Chlorine isotope composition in chlorofluorocarbons CFC-11, CFC-12 and CFC-113 in firn, stratospheric and tropospheric air, in Atmospheric Chemistry and Physics
, 15(12), 6867-6877.
Eicher O., Baumgartner M., Schilt A., Schmitt J., Schwander J., Stocker T. F., Fischer H. (2015), Climatic and insolation control on the high-resolution total air content in the NGRIP ice core, in Climate of the Past Discussions
, 11(6), 5509-5548.
(2015), Continental-scale temperature variability in PMIP3 simulations and PAGES 2k regional temperature reconstructions over the past millennium, in Climate of the Past
, 11, 1673-1699.
van der Wel G., Fischer H., Oerter H., Meyer H., Meijer H. A. J. (2015), Estimation and calibration of the water isotope differential diffusion length in ice core records, in The Cryosphere
, 9(4), 1601-1616.
Grams Christian M., Blumer Sandro R. (2015), European high-impact weather caused by the downstream response to the extratropical transition of North Atlantic Hurricane Katia (2011), in Geophysical Research Letters
, 42(20), 8738-8748.
Zennaro P., Kehrwald N., McConnell J. R., Schüpbach S., Maselli O. J., Marlon J., Vallelonga P., Leuenberger D., Zangrando R., Spolaor A., Borrotti M., Barbaro E., Gambaro A., Barbante C. (2015), Fire in ice: two millennia of boreal forest fire history from the Greenland NEEM ice core, in Climate of the Past
, 10(5), 1905-1924.
Lehner Flavio, Stocker Thomas F. (2015), From local perception to global perspective, in Nature Climate Change
, 5(8), 731-734.
Miteva Vanya, Sowers Todd, Schüpbach Simon, Fischer Hubertus, Brenchley Jean (2015), Geochemical and Microbiological Studies of Nitrous Oxide Variations within the New NEEM Greenland Ice Core during the Last Glacial Period, in Geomicrobiology Journal
, 33(8), 647-660.
Fischer Hubertus, Schüpbach Simon, Gfeller Gideon, Bigler Matthias, Röthlisberger Regine, Erhardt Tobias, Stocker Thomas F., Mulvaney Robert, Wolff Eric W. (2015), Millennial changes in North American wildfire and soil activity over the last glacial cycle, in Nature Geoscience
, 8(9), 723-727.
Kobashi T., Box J. E., Vinther B. M., Goto-Azuma K., Blunier T., White J. W. C., Nakaegawa T., Andresen C. S. (2015), Modern solar maximum forced late twentieth century Greenland cooling, in Geophysical Research Letters
, 42(14), 5992-5999.
Stocker B. D., Joos F. (2015), Quantifying differences in land use emission estimates implied by definition discrepancies, in Earth System Dynamics
, 6(2), 731-744.
Zanchettin D., Bothe O., Lehner F., Ortega P., Raible C. C., Swingedouw D. (2015), Reconciling reconstructed and simulated features of the winter Pacific/North American pattern in the early 19th century, in Climate of the Past
, 11(6), 939-958.
Tison J.-L., de Angelis M., Littot G., Wolff E., Fischer H., Hansson M., Bigler M., Udisti R., Wegner A., Jouzel J., Stenni B., Johnsen S., Masson-Delmotte V., Landais A., Lipenkov V., Loulergue L., Barnola J.-M., Petit J.-R., Delmonte B., Dreyfus G., Dahl-Jensen D., Durand G., Bereiter B., Schilt A., et al. (2015), Retrieving the paleoclimatic signal from the deeper part of the EPICA Dome C ice core, in The Cryosphere
, 9(4), 1633-1648.
Wegner Anna, Fischer Hubertus, Delmonte Barbara, Petit Jean-Robert, Erhardt Tobias, Ruth Urs, Svensson Anders, Vinther Bo, Miller Heinrich (2015), The role of seasonality of mineral dust concentration and size on glacial/interglacial dust changes in the EPICA Dronning Maud Land ice core, in Journal of Geophysical Research: Atmospheres
, 120(19), 9916-9931.
Sigl M., Winstrup M., McConnell J. R., Welten K. C., Plunkett G., Ludlow F., Büntgen U., Caffee M., Chellman N., Dahl-Jensen D., Fischer H., Kipfstuhl S., Kostick C., Maselli O. J., Mekhaldi F., Mulvaney R., Muscheler R., Pasteris D. R., Pilcher J. R., Salzer M., Schüpbach S., Steffensen J. P., Vinther B. M., Woodruff T. E. (2015), Timing and climate forcing of volcanic eruptions for the past 2,500 years, in Nature
, 523(7562), 543-549.
Bohn T. J., Melton J. R., Ito A., Kleinen T., Spahni R., Stocker B. D., Zhang B., Zhu X., Schroeder R., Glagolev M. V., Maksyutov S., Brovkin V., Chen G., Denisov S. N., Eliseev A. V., Gallego-Sala A., McDonald K. C., Rawlins M.A., Riley W. J., Subin Z. M., Tian H., Zhuang Q., Kaplan J. O. (2015), WETCHIMP-WSL: intercomparison of wetland methane emissions models over West Siberia, in Biogeosciences
, 12(11), 3321-3349.
Earth System models, ranging from reduced-complexity to comprehensive, are developed and used to address questions of past and future climate change. Reduced-complexity models are coupled to dynamical carbon cycle modules, water mass tracers for paleoceanographic studies, and a dynamic vegetation model with peat and wetland processes for CH4 and N2O budgets. For the comprehensive model we will complete the development of a carbon isotope module for the land processes. In the coming funding period we will employ these models to investigate new paleoceanographic tracers (9Be, 10Be) and perform joint simulations with the entire water mass tracers over glacial-interglacial cycles before and after the Mid-Pleistocene Revolution, and through a series abrupt climate events typical of the last ice age. Simulations will include the noble gas tracers in the ocean and the results will be applied to emerging new ice core data from our division for whole-ocean temperature reconstructions. Fully coupled climate-carbon cycle model experiments address the question of climate-carbon sensitivity and transient carbon budgets in peat and wetland areas. They will also provide the basis for consistent interpretation of novel isotopic data from polar ice cores. Comprehensive models will also be used to investigate atmospheric dynamics and their role during the past millennium for specific climate periods. Finally, we will perform ensemble simulations for future climate change to investigate mitigation delay sensitivities of the climate system.Reconstructing past climate change will be based primarily on comprehensive measurements of greenhouse gas concentrations and air components, including most of their stable isotopes, and the palette of high-resolution chemical compounds in ice cores from Greenland and Antarctica. Interpretations of these measurements will be facilitated, where possible, with dedicated climate-carbon cycle models to constrain the history of exchange fluxes of carbon. In the coming two years we will close the low-resolution gap in CO2 measurements between 150 and 450,000 years. ?13CO2 measurements will focus on one entire glacial cycle and on milder interglacials before 450,000 years before present. The continuous flow analyses (CFA) will be used to unravel past atmospheric dynamics and modes of variability on the Greenland and Antarctic ice sheets. The focus will lie on a high-resolution comparison of Eemian and Holocene records to gain further insight into the characteristic differences of these warm phases. This study will be enabled by simulations using a comprehensive climate model. A deep ice core drilling in the Neumayer Hinterland, Antarctica, is projected for the austral season 2015/16 in a German-Swiss cooperation. If successful we will obtain new ice which will provide unique access to Holocene greenhouse gas concentrations and Antarctic climate variability in high resolution.Isotope analyses is a state-of-the-art tool in environmental physics. They provide independent constraints of fluxes, permit the estimate of reservoir sizes, and the determination of age or renewal times of constituents. We utilize our unique palette of natural radio-nuclides (14C, 81Kr, 85Kr, 37Ar, 39Ar) to date groundwaters and to estimate underground production, both natural and anthropogenic. In the coming two years we will investigate the contamination of aquifers by the industrial use of salt on roads during winter time and the dynamics of arsenic pollution. Such studies require a reliable dating of the aquifer which is enabled by our radionuclide concentrations. Very old waters are dated using 81Kr, which requires a complex purification step prior to atom trap trace analysis. The very old waters also contain climate information through concentrations of noble gases. In the coming two years we strengthen the new collaborations with the ice core community to date very old ice from blue ice zones in Antarctica.Innovation of the experimental infrastructure will be continued. For the CFA device we are developing a new dust size sensor. This important quantity provides a wealth of information regarding atmospheric flow, precipitation origin and deposition history. Dust concentration and size will be determined by the classical Coulter Counter principle adjusted to the specific CFA setup. In the next two years we will complete our new ice drilling equipment for field testing in Greenland. The goal is to drill within a few days a thin hole down to bedrock using a small-diameter hydro-powered drill. Such a hole will provide rapid access to temperature and dust profile measurements and recovery of deep ice samples to aid site selection in the "Oldest Ice" project.