Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-27T11:48:24.312Z Has data issue: false hasContentIssue false

Abrupt climate change: An alternative view

Published online by Cambridge University Press:  20 January 2017

Carl Wunsch*
Affiliation:
Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
*
E-mail address:cwunsch@mit.edu

Abstract

Hypotheses and inferences concerning the nature of abrupt climate change, exemplified by the Dansgaard–Oeschger (D–O) events, are reviewed. There is little concrete evidence that these events are more than a regional Greenland phenomenon. The partial coherence of ice core δ18O and CH4 is a possible exception. Claims, however, of D–O presence in most remote locations cannot be distinguished from the hypothesis that many regions are just exhibiting temporal variability in climate proxies with approximately similar frequency content. Further suggestions that D–O events in Greenland are generated by shifts in the North Atlantic ocean circulation seem highly implausible, given the weak contribution of the high latitude ocean to the meridional flux of heat. A more likely scenario is that changes in the ocean circulation are a consequence of wind shifts. The disappearance of D–O events in the Holocene coincides with the disappearance also of the Laurentide and Fennoscandian ice sheets. It is thus suggested that D–O events are a consequence of interactions of the windfield with the continental ice sheets and that better understanding of the wind field in the glacial periods is the highest priority. Wind fields are capable of great volatility and very rapid global-scale teleconnections, and they are efficient generators of oceanic circulation changes and (more speculatively) of multiple states relative to great ice sheets. Connection of D–O events to the possibility of modern abrupt climate change rests on a very weak chain of assumptions.

Type
QR Forum
Copyright
University of Washington

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Alley, R.B., (2005). Abrupt climate changes, oceans, ice, and us. Oceanography 17, 194206.CrossRefGoogle Scholar
Barrow, J.D., Bhavasar, S.P., (1987). Filaments: what the astronomer's eye tells the astronomer's brain. Quarterly Journal of the Royal Astronomical Society 28, 109128.Google Scholar
Bond, G., Broecker, W., Johnsen, S., McManus, J., Labeyrie, L., Jouzel, J., Bonani, G., (1993). Correlations between climate records from North Atlantic sediments and Greenland ice. Nature 365, 143147.CrossRefGoogle Scholar
Boyle, E., (1995). Last-glacial maximum north Atlantic deep water: on, off or somewhere in-between. Philosophical transactions of the Royal Society of London. B 348, 243253.Google Scholar
Broecker, W.S., (1997). Thermohaline circulation, the Achilles heel of our climate system: will man-made C02 upset the current balance?. Science 278, 15821588.CrossRefGoogle Scholar
Broecker, W.S., (2003). Does the trigger for abrupt climate change reside in the ocean or in the atmosphere?. Science 300, 15191522.CrossRefGoogle ScholarPubMed
Buck, C.E., Millard, A.R., (2004). Tools for Constructing Chronologies. Crossing Disciplinary Boundaries. Springer-Verlag, London.257 pp.Google Scholar
Cartwright, D.E., Longuet-Higgins, M.S., (1956). The statistical distributions of the maxima of a random function. Proceedings of the Royal Society, A 237, 212232.Google Scholar
Chappellaz, J.A., Fung, I.Y., Kucsera, T.L., (1993). The atmospheric CH4 increase since the last glacial maximum. Tellus 45B, 228241.CrossRefGoogle Scholar
Cruz, F.W. Jr. (2005). Insolation-driven changes in atmospheric circulation over the past 116,000 years in subtropical Brazil. Nature 434, 6366.CrossRefGoogle Scholar
Curry, W.B., Oppo, D.W., (2005). Glacial water mass geometry and the distribution of VC and TC02 in the western Atlantic Ocean. Paleoceanography 20, PA1017doi:10.1029/2004PA001021.CrossRefGoogle Scholar
Dansgaard, W., (1987). Ice core evidence of abrupt climatic changes. Berger, W.H., Labeyrie, L.D., Abrupt Climatic Change. Evidence and Implications D. Reidel, Dordrecht.223233.CrossRefGoogle Scholar
Diaconis, P., Mosteller, F., (1989). Methods for studying coincidences. Journal of the American Statistical Association 84, 853861.CrossRefGoogle Scholar
Farrell, B.F., loannou, P.J., (2003). Structural stability of turbulent jets. Journal of the Atmospheric Sciences 60, 21012118.2.0.CO;2>CrossRefGoogle Scholar
Fliikiger, T., Blunier, B., Stauffer, J., Chappella, R., Spalini, K., Kawamura, J., Schwander, T., Stocker, F., Dahl-Jensen, D., (2004). N20 and CH4 variations during the last glacial epoch: insight into global processes. Global Biogeochem. Cycles 18, GB1020doi:10.1029/2003GB002122.Google Scholar
Friedman, L., Smith, G.1., Johnson, C.A., Moscati, R.J., (2002). Stable isotope compositions of waters in the Great Basin, United States—2. Modern precipitation. Journal of Geophysical Research, [atmosphere] D19, 107(Article No. 4401)Google Scholar
Ganachaud, A., (1999). Large Scale Oceanic Circulation and Fluxes of Freshwater, Heat, Nutrients and Oxygen. PhD thesis, MIT/WHOI, 266 pp.Google Scholar
Ganachaud, A., Wunsch, C., (2002). Large-scale ocean heat and freshwater transports during the World Ocean Circulation Experiment. Journal of Climate 16, 696705.2.0.CO;2>CrossRefGoogle Scholar
Guardian, The, London, (2005). Hotter World May Freeze Britain. The Guardian, London.2 February 2005 article by P. Brown Guardian, The, LondonGoogle Scholar
Hendy, 1.L., Kennett, J.P., Roark, E.B., Ingrain, B.L., (2002). Apparent synchorneity of submillennial scale climate events between Greenland and Santa Barbara Basin, California from 20–10 ka. Quaternary Science Reviews 21, 11671184.CrossRefGoogle Scholar
Hendy, 1.L., Pedersen, T.F., Kennett, J.P., Tada, R., (2004). Intermittent existence of a southern Californian upwelling cell during submillennial climate change of the last 60 kyr. Paleoceanography 19, doi:10.1029/2003PA000965.CrossRefGoogle Scholar
Huang, R.X., (1993). Real freshwater flux as a natural boundary condition for the salinity balance and thermohaline circulation forced by evaporation and precipitation. Journal of Physical Oceanography 23, 24282446.2.0.CO;2>CrossRefGoogle Scholar
Jackson, C., (2000). Sensitivity of stationary wave amplitude to regional changes in Laurentide ice sheet topography in single-layer models of the atmosphere. Journal of Geophysical Research 105, 24,44324,454.CrossRefGoogle Scholar
Jouzel, J., Alley, R.B., Cuffey, K.M., Dansgaard, W., Grootes, P., Hoffmann, G., Johnsen, S.J., Koster, R.D., Peel, D., Shuman, C.A., Stievenard, M., Stuiver, M., White, J., (1997). Validity of the temperature reconstruction from water isotopes in ice cores. Journal of Geophysical Research 102, 26,47126,487.CrossRefGoogle Scholar
Justino, F., Timmermann, F., Merkel, U., Souza, E.P., (2005). Synoptic reorganization of atmospheric flow during the last glacial maximum. Journal of Climate 18, 28262846.CrossRefGoogle Scholar
Kahneman, D., Slovic, P., Tversky, A., (1982). Judgment Under Uncertainty: Heuristics and Biases. Cambridge Univ. Press, Cambridge.555 pp.CrossRefGoogle Scholar
Kutzbach, J.E., Guetter, P.E., (1986). The influence of changing orbital parameters and surface boundary conditions on climate simulations for the past 18,000 years. Journal of the Atmospheric Sciences 43, 17261759.2.0.CO;2>CrossRefGoogle Scholar
Landais, A., Baxnola, J.M., Masson-Delmotte, V., Jouzel, J., Chappellaz, J., Caillon, N., Huber, C., Leuenberger, M., Johnsen, S.J., (2004). A continuous record of temperature evolution over a sequence of Dansgaard–Oeschger events during Marine Isotope Stage 4 (76 to 62 kyr BP). Geophysical Research Letters 31, doi:10.1029/2004GL021193.CrossRefGoogle Scholar
Large, W.G., McWilliams, J.C., Doney, S.C., (1994). Oceanic vertical mixing: a review and a model with nonlocal boundary layer parameters. Review of Geophysics 32, 363403.CrossRefGoogle Scholar
Larsen, G., Bierbooms, C.W., Hansen, K.S., (2003). Statistics of Local Extremes. Riso/R-1220 (EN) Riso/National Laboratory. Roskilde, Denmark.62 pp.Google Scholar
Li, C., Battisti, D.S., Schrag, D.P., Tziperman, E., (2005). Abrupt climate shifts in Greenland due to displacements of the sea ice edge. Geophysical Research Letters 32, doi:10.1029/2005GL023492.CrossRefGoogle Scholar
Manabe, S., Stouffer, R.J., (1999). Are two modes of thermohaline circulation stable?. Tellus 51A, 400411.CrossRefGoogle Scholar
Moore, M.I., Thomson, P.J., (1991). Impact of jittered sampling on conventional spectral estimates. Journal of Geophysical Research 96, 18,51918,526.CrossRefGoogle Scholar
Munk, W., Wunsch, C., (1998). Abyssal recipes II: energetics of tidal and wind mixing. Deep-sea Research 45, 19762009.CrossRefGoogle Scholar
Neelin, J.D., Battisti, D.S., Hirst, A.C., Jin, F.-F., Wakata, Y., Yamagata, T., Zebiak, S.E., (1998). ENSO theory. Journal of Geophysical Research 103, 14,29014,621.CrossRefGoogle Scholar
Newman, W.L., Haynes, M.P., Terzian, Y., (1994). Redshift data and statistical inference. AP Journal 431, 147155.CrossRefGoogle Scholar
Nilsson, J., Broström, G., Walin, G., (2003). The thermohaline circulation and vertical mixing: does weaker density stratification give stronger overturning?. Journal of Physical Oceanography 33, 27812795.2.0.CO;2>CrossRefGoogle Scholar
Pedlosky, J., (1996). Ocean Circulation Theory. Springer-Verlag, Berlin.450 pp.CrossRefGoogle Scholar
Peltier, W.R., (1994). Ice age paleotopography. Science 265, 195201.CrossRefGoogle ScholarPubMed
Peltier, W.R., (1995). Paleotopography of glacial-age ice sheets—Reply. Science 267, 536538.Google Scholar
Peterson, L.C., Haug, G.H., Hughen, K.A., Rohl, U., (2000). Rapid changes in the hydrologic cycle of the tropical Atlantic during the last glacial. Science 290, 19471951.CrossRefGoogle ScholarPubMed
Price, J.F., Weller, R.A., Pinkel, R., (1986). Diurnal cycling: observations and models of the upper ocean response to diurnal heat, cooling, and wind mixing. Journal of Geophysical Research 91, 84118427.CrossRefGoogle Scholar
Roe, G.H., Lindzen, R.S., (2001). The mutual interaction between continental-scale ice sheets and atmospheric stationary waves. Journal of Climate 14, 14501465.2.0.CO;2>CrossRefGoogle Scholar
Schiermeier, Q., (2004). Gulf Stream probed for early warnings of system failure. Nature 427, 769.CrossRefGoogle ScholarPubMed
Schmittner, A., (2005). Decline of the marine ecosystem caused by a reduction in the Atlantic overturning circulation. Nature 434, 628633.CrossRefGoogle ScholarPubMed
Schulz, H., von Rad, U., Erlenkeuser, H., (1998). Correlation between Arabian Sea and Greenland climate oscillations of the past 110,000 years. Nature 393, 5457.CrossRefGoogle Scholar
Severinghaus, J.P., Brook, E.J., (1999). Abrupt climate change at the end of the last glacial period inferred from trapped air in polar ice. Science 286, 930934.CrossRefGoogle ScholarPubMed
Severinghaus, J.P., Sowers, T., Brook, E.J., Alley, R.B., Bender, M.L., (1998). Timing of abrupt climate change at the end of the Younger Dryas interval from thermally fractionated gases in polar ice. Nature 391, 141146.CrossRefGoogle Scholar
Stone, P.H., (1978). Constraints on dynamical transports of energy on a spherical planet. Dynamics of Atmospheres and Oceans 2, 123139.CrossRefGoogle Scholar
Stuiver, M., Grootes, P.M., (2000). GISP2 oxygen isotope ratios. Quaternary Research 53, 277284.CrossRefGoogle Scholar
Vanmarcke, E., (1983). Random Fields: Analysis and Synthesis. The MIT Press, Cambridge.382 pp.Google Scholar
Wang, Y.J., Cheng, H., Edwards, R.L., An, Z.S., Wun, J.Y., Shen, C.C., Dorale, J.A., (2001). A high-resolution absolute-dated Late Pleistocene monsoon record from Hulu Cave. Science 294, 23452348.CrossRefGoogle ScholarPubMed
Wunsch, C., (2000). On sharp spectral lines in the climate record and the millennial peak. Paleoceanography 15, 417424.CrossRefGoogle Scholar
Wunsch, C., (2002). What is the thermohaline circulation?. Science 298, 11801181.CrossRefGoogle ScholarPubMed
Wunsch, C., (2003a). Greenland-Antarctic phase relations and millennial time-scale fluctuations in the Greenland cores,. Quaternary Science Reviews 22/15–17, 16311646.CrossRefGoogle Scholar
Wunsch, C., (2003b). Determining paleoceanographic circulations, with emphasis on the Last Glacial Maximum. Quaternary Science Reviews 22/2–4, 371385.CrossRefGoogle Scholar
Wunsch, C., (2005). The total meridional heat flux and its oceanic and atmospheric partition. Journal of Climate 18, 43744380.CrossRefGoogle Scholar
Wunsch, C., Ferrari, R., (2004). Vertical mixing, energy, and the general circulation of the oceans. Annual Review of Fluid Mechanics 36, 281314.CrossRefGoogle Scholar
Wunsch, C., Gunn, D.E., (2003). A densely sampled core and climate variable aliasing. Geo-marine Letters 23, 1 6471.CrossRefGoogle Scholar
Yu, E.-F., François, R., Bacon, M.P., (1996). Similar rates of modern and last-glacial ocean thermohaline circulation inferred from radiochemical data. Nature 379, 689694.CrossRefGoogle Scholar