Nick Shackleton the Passing of a Giant
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Success and Failure of Milankovitch Theory
UC San Diego Scripps Institution of Oceanography Technical Report Title Miklankovitch Theory - Hits and Misses Permalink https://escholarship.org/uc/item/95m6h5b9 Author Berger, W H Publication Date 2012-01-16 eScholarship.org Powered by the California Digital Library University of California MILANKOVITCH THEORY – HITS AND MISSES W.H. Berger, Scripps Institution of Oceanography, UCSD, La Jolla, Calif. Abstract Milankovitch Theory has become an important tool in geologic practice and thought, and is sufficiently conspicuous to provide a rewarding target for criticism. The chief problem arising has to do with the prominence of a cycle near 100,000 years, whose origin is not clear. Most practitioners, presumably, would accept a close relationship of that cycle to precession of the equinoxes (that is, cyclic changes in seasonality), along with dynamical properties of the system that enhance the amplitude of the 100-kyr cycle at the expense of others. In any case, Milankovitch Theory has proved useful, both for age assignments and for stimulating thought about relationships between climate change and sedimentation, as is readily evident from the relevant literature. It would be difficult to replace. Neither does it seem desirable to do so: the chief problem noted in regard of the theory (the 100-kyr problem) is not necessarily a part of the theory, which is concerned with change rather than with condition. The 100-kyr cycle is linked to condition. The problem raised by critics seems to be the time scale of integration of change, a problem not addressed in Milankovitch Theory. A necessity for additional processes and mechanisms not considered in Milankovitch Theory cannot be excluded. -
Milankovitch's Other Unsolved Mystery
PALEOCEANOGRAPHY, VOL. 18, NO. 1, 1011, doi:10.1029/2002PA000791, 2003 The 41 kyr world: Milankovitch’s other unsolved mystery Maureen E. Raymo Department of Earth Sciences, Boston University, Boston, Massachusetts, USA Kerim Nisancioglu Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA Received 26 March 2002; revised 5 September 2002; accepted 19 September 2002; published 6 March 2003. [1] For most of the Northern Hemisphere Ice Ages, from 3.0 to 0.8 m.y., global ice volume varied predominantly at the 41,000 year period of Earth’s orbital obliquity. However, summer (or summer caloric half year) insolation at high latitudes, which is widely believed to be the major influence on high-latitude climate and ice volume, is dominated by the 23,000 year precessional period. Thus the geologic record poses a challenge to our understanding of climate dynamics. Here we propose that variations in the insolation gradient between high and low latitudes control high-latitude climate and ice volume during the late Pliocene and early Pleistocene. The differential heating between high and low latitudes, driven by obliquity, controls the atmospheric meridional flux of heat, moisture, and latent energy, which may exert the dominant control on high-latitude climate on Milankovitch timescales. In the two-dimensional zonal energy balance models typically used to study the long- term evolution of climate, the meridional atmospheric moisture flux is usually kept fixed. The hypothesis that insolation gradients control the poleward energy fluxes, precipitation, and ice volume at high latitudes has never been directly examined within the context of an ice sheet model. -
Curriculum Vitae Warren L
1 BROWN UNIVERSITY CURRICULUM VITAE WARREN L. PRELL Henry L. Doherty Professor Department of Geological Sciences Brown University 1. Warren L Prell Henry L. Doherty Professor of Oceanography Department of Geological Sciences, Box 1846 Brown University, Providence, RI 02912 (401) 863-3221 3. EDUCATION B.A. Hanover College, 1966 Honors: Department Honors in Geology, Hanover College, Alumni Award, Phi Eta Sigma (Scholastic Honor) Ph.D. Columbia University, 1974 Topic: Late Pleistocene Sedimentary, Faunal and Temperature History of the Colombia Basin, Caribbean Sea M.A. Brown University (ad eundem), 1981 4. PROFESSIONAL APPOINTMENTS 2005-2008 Chair, Department of Geological Sciences 1990- Henry L. Doherty Chair in Oceanography, Department of Geological Sciences, Brown University, Providence, RI 1989- Professor, Department of Geological Sciences, Brown University 1989-1993 Chair, Department of Geological Sciences 1982-1989 Associate Professor, Department of Geological Sciences 1980-1981 Associate Professor (Research), Department of Geological Sciences 1975-1980 Assistant Professor (Research), Department of Geological Sciences 1973-1975 Director of Oceanographic and Geologic Programs, New York State Energy Research and Development Authority, New York City: Related Professional Experience 2002-2004 Chair of US Science Advisory Committee to the Joint Oceanographic Incorporated and US Science Support Program. 1999 Co-Chief Scientist, Ocean Drilling Program Leg 184 (South China Sea) 1995 Co-Chief Scientist, TN 047 JGOFS Arabian Sea Process Study, RV T. Thompson, Arabian Sea, May, Muscat-Muscat 1994 Co-Chief Scientist, TN 041 JGOFS Arabian Sea Process Study, RV T. Thompson, Arabian Sea, October, Muscat-Muscat 1993-94 Visiting Professor, College of Oceanic and Atmospheric Sciences, Oregon State University 1987 Chief Scientist, NSF Ocean Drilling Program Leg 117, Arabian Sea, Indian Ocean 1986 Chief Scientist, Arabian Sea Monsoon Expedition, on R/V Robert C. -
Tying Celestial Mechanics to Earth's Ice Ages
Tying celestial mechanics to Earth’s ice ages Mark Maslin Citation: Physics Today 73, 5, 48 (2020); doi: 10.1063/PT.3.4474 View online: https://doi.org/10.1063/PT.3.4474 View Table of Contents: https://physicstoday.scitation.org/toc/pto/73/5 Published by the American Institute of Physics ARTICLES YOU MAY BE INTERESTED IN Negative carbon dioxide emissions Physics Today 73, 44 (2020); https://doi.org/10.1063/PT.3.4389 Gravitational-lensing measurements push Hubble-constant discrepancy past 5σ Physics Today 73, 14 (2020); https://doi.org/10.1063/PT.3.4424 John Wheeler’s H-bomb blues Physics Today 72, 42 (2019); https://doi.org/10.1063/PT.3.4364 Between complacency and panic Physics Today 73, 40 (2020); https://doi.org/10.1063/PT.3.4453 The speedy secret of shark skin Physics Today 73, 58 (2020); https://doi.org/10.1063/PT.3.4460 Particle beams behind physics discoveries Physics Today 73, 32 (2020); https://doi.org/10.1063/PT.3.4452 Uganda‘s Margherita glacier, in the Rwenzori Mountains, provides the Nile River with some of its water. (Morgan Trimble/Alamy Stock Photo.) 48 PHYSICS TODAY | MAY 2020 Mark Maslin is a professor of Earth system science in the department of geography at University College London. Tying celestial mechanics to Earth’s ice ages Gradual falls and sharp rises in temperature for millions of years have profoundly affected living conditions on the planet and, consequently, our own evolution. Mark Maslin ilutin Milanković, a brilliant Serbian mathematician and climatologist, postulated in 1941 that variations in Earth’s orbit could push the planet’s climate in or out of an ice age.1 Vital to that idea is the amount of insolation—incoming Msolar radiation—at 65°N, a bit south of the Arctic Circle. -
The Earth's Glacial Cycles
Math and Climate Seminar IMA Glacial Cycles Last Week’s News Joint MCRN/IMA Math and Climate Seminar Tuesdays 11:15 – 12:05 streaming video available at www.ima.umn.edu http://nsidc.org/arcticseaicenews/ Glacial Cycles The Earth’s Glacial Cycles Last Week’s News Richard McGehee Seminar on the Mathematics of Climate IMA, MCRN, School of Mathematics September 25, 2012 http://www.nytimes.com/2012/09/19/science/earth/arctic-resources-exposed-by-warming-set-off-competition.html Glacial Cycles Glacial Cycles 18O as a Climate Proxy Temperatures in the Cenozoic Era The isotope 16O preferentially evaporates from the ocean and is sequestered in glaciers, leaving the heavier isotope 18O more highly concentrated in the ocean. Thus oceanic concentration of the isotope 18O is higher during glacial periods. Foraminifera absorb more 18O into their skeletons when the water temperature is lower and when more 18O is in the water. Thus higher concentrations of 18O in foraminifera fossils indicate lower ocean temperatures and higher glacier volume. Hansen, et al, Target atmospheric CO2: Where should humanity aim? Open Atmos. Sci. J. 2 (2008) 1 Glacial Cycles Glacial Cycles 18O in Foraminifera Fossils During the Past 4.5 Myr 18O in Foraminifera Fossils During the Past 1.0 Myr 2.5 2.5 3 3 3.5 18O) 3.5 δ 18O) ( δ ( 4 Data 4 Data 4.5 4.5 Benthic Benthic 5 5 5.5 5.5 ‐4500 ‐4000 ‐3500 ‐3000 ‐2500 ‐2000 ‐1500 ‐1000 ‐500 0 ‐1000 ‐900 ‐800 ‐700 ‐600 ‐500 ‐400 ‐300 ‐200 ‐100 0 time (Kyr) time (Kyr) Lisiecki, L. -
Last Interglacial Climates
University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln USGS Staff -- Published Research US Geological Survey 2002 Last Interglacial Climates George J. Kukla Lamont-Doherty Earth Observatory Michael L. Bender Princeton University Jacques-Louis de Beaulieu Faculte des Sciences et Techniques St. Jerome Gerard Bond Lamont-Doherty Earth Observatory Wallace S. Broecker Lamont-Doherty Earth Observatory See next page for additional authors Follow this and additional works at: https://digitalcommons.unl.edu/usgsstaffpub Part of the Earth Sciences Commons Kukla, George J.; Bender, Michael L.; de Beaulieu, Jacques-Louis; Bond, Gerard; Broecker, Wallace S.; Cleveringa, Piet; Gavin, Joyce E.; Herbert, Timothy D.; Imbrie, John; Jouzel, Jean; Keigwin, Lloyd D.; Knudsen, Karen-Luise; McManus, Jerry F.; Merkt, Josef; Muhs, Daniel R.; Muller, Helmut; Poore, Richard Z.; Porter, Stephen C.; Seret, Guy; Shackleton, Nicholas J.; Turner, Charles; Tzedakis, Polychronis C.; and Winograd, Isaac J., "Last Interglacial Climates" (2002). USGS Staff -- Published Research. 174. https://digitalcommons.unl.edu/usgsstaffpub/174 This Article is brought to you for free and open access by the US Geological Survey at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in USGS Staff -- Published Research by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. Authors George J. Kukla, Michael L. Bender, Jacques-Louis de Beaulieu, Gerard Bond, Wallace S. Broecker, Piet Cleveringa, Joyce E. Gavin, Timothy D. Herbert, John Imbrie, Jean Jouzel, Lloyd D. Keigwin, Karen-Luise Knudsen, Jerry F. McManus, Josef Merkt, Daniel R. Muhs, Helmut Muller, Richard Z. Poore, Stephen C. Porter, Guy Seret, Nicholas J. Shackleton, Charles Turner, Polychronis C. Tzedakis, and Isaac J.