Academia.eduAcademia.edu

Outline

Title
Abstract
Motivation and Findings
References
All Topics
Earth Sciences
Global and Planetary Change

Abrupt changes and the astronomical theory of climate?

Profile image of Michael GhilMichael Ghil

2021

Abstract

The past 3.2 Myr have seen drastic climate changes with the development, waxing and waning of huge continental ice sheets over the Northern Hemisphere. These striking phenomena have been observed in various records from ice cores, as well as marine and terrestrial sediments. These proxy records showed periodicities associated with the three orbital parameters that affect our planet’s insolation, namely eccentricity, obliquity and precession. Until recently, these periodicities were considered as the canonical ones for the Quaternary Period and beyond. However, the improvement of the time resolution of available records has allowed one to describe climate changes occurring abruptly and with periodicities that are not related to those of the orbital parameters. In this paper, we show that, in fact, these abrupt climate changes may still be related, albeit indirectly, to the astronomical theory of climate.

Related papers

Extreme Climate Variations from Milankovitch-like Eccentricity Oscillations in Extrasolar Planetary Systems
Dave Spiegel

2010

Although our solar system features predominantly circular orbits, the exoplanets discovered so far indicate that this is the exception rather than the rule. This could have crucial consequences for exoplanet climates, both because eccentric terrestrial exoplanets could have extreme seasonal variations, and because giant planets on eccentric orbits could excite Milankovitch-like variations of a potentially habitable terrestrial planets eccentricity, on timescales of thousandsto-millions of years. A particularly interesting implication concerns the fact that the Earth is thought to have gone through at least one globally frozen, "snowball" state in the last billion years that it presumably exited after several million years of buildup of greenhouse gases when the ice-cover shut off the carbonatesilicate cycle. Water-rich extrasolar terrestrial planets with the capacity to host life might be at risk of falling into similar snowball states. Here we show that if a terrestrial planet has a giant companion on a sufficiently eccentric orbit, it can undergo Milankovitch-like oscillations of eccentricity of great enough magnitude to melt out of a snowball state. Proceeding Even very mild astronomical forcings can have dramatic influence on the Earth's climate. Although the orbital eccentricity varies between ∼0 and only ∼0.06, and the axial tilt, or obliquity, between ∼22.1 • and 24.5 • , these slight quasi-periodic changes are sufficient to help drive the Earth into ice ages at regular intervals. Milankovitch articulated this possibility in his astronomical theory of climate change. Specifically, Milankovitch posited a causal connection between three astronomical cycles (precession-23 kyr period, and variation of both obliquity and eccentricity-41-kyr and 100-kyr periods, respectively) and the onset of glaciation/deglaciation. Though much remains to be discovered about these cycles, often in the literature referred to as "Milankovitch cycles," 1 they are now generally acknowledged to

View PDFchevron_right
Empirical evidence for a celestial origin of the climate oscillations and its implications
Nicola Scafetta

Journal of Atmospheric and Solar-Terrestrial Physics, 2010

We investigate whether or not the decadal and multi-decadal climate oscillations have an astronomical origin. Several global surface temperature records since 1850 and records deduced from the orbits of the planets present very similar power spectra. Eleven frequencies with period between 5 and 100 years closely correspond in the two records. Among them, large climate oscillations with peak-to-trough amplitude of about 0.1 o C and 0.25 o C, and periods of about 20 and 60 years, respectively, are synchronized to the orbital periods of Jupiter and Saturn. Schwabe and Hale solar cycles are also visible in the temperature records. A 9.1-year cycle is synchronized to the Moon's orbital cycles. A phenomenological model based on these astronomical cycles can be used to well reconstruct the temperature oscillations since 1850 and to make partial forecasts for the 21 st century. It is found that at least 60% of the global warming observed since 1970 has been induced by the combined effect of the above natural climate oscillations. The partial forecast indicates that climate may stabilize or cool until 2030-2040. Possible physical mechanisms are qualitatively discussed with an emphasis on the phenomenon of collective synchronization of coupled oscillators. Please cite this article as: Scafetta, N., Empirical evidence for a celestial origin of the climate oscillations and its implications.

View PDFchevron_right
Astronomical theory of climate change
Andre Berger

Journal de Physique IV (Proceedings), 2004

The tilt of the earth relative to its plane of travel about the sun is what causes seasons. The hemisphere "pointing toward" the sun is in summer, while the opposite hemisphere is in winter. The earth makes one full orbit around the sun each year. The northern hemisphere is in summer in the left image, while 6 months later, the southern hemisphere has summer, as in the center image. If the earth's axis were "straight up and down" relative to the orbital plane, as in the right-hand image, there would be no seasons, since any given point at the top of the atmosphere would receive the same amount of sun each day of the year. Changes in the "tilt" of the earth can change the severity of the seasons-more "tilt" means more severe seasons-warmer summers and colder winters; less "tilt" means less severe seasons-cooler summers and milder winters. The earth wobbles in space so that its tilt changes between about 22 and 25 degrees on a cycle of about 41,000 years. It is the cool summers which are thought to allow snow and ice to last from year to year in high latitudes, eventually building up into massive ice sheets. There are positive feedbacks in the climate system as well, because an earth covered with more snow reflects more of the sun's energy into space, causing additional cooling. In addition, it appears that the amount of Carbon Dioxide in the atmosphere falls as ice sheets grow, also adding to the cooling of the climate.

View PDFchevron_right
Orbital forcing of climate 1.4 billion years ago
Emma Hammarlund

Proceedings of the National Academy of Sciences of the United States of America, 2015

Fluctuating climate is a hallmark of Earth. As one transcends deep into Earth time, however, both the evidence for and the causes of climate change become difficult to establish. We report geochemical and sedimentological evidence for repeated, short-term climate fluctuations from the exceptionally well-preserved ∼1.4-billion-year-old Xiamaling Formation of the North China Craton. We observe two patterns of climate fluctuations: On long time scales, over what amounts to tens of millions of years, sediments of the Xiamaling Formation record changes in geochemistry consistent with long-term changes in the location of the Xiamaling relative to the position of the Intertropical Convergence Zone. On shorter time scales, and within a precisely calibrated stratigraphic framework, cyclicity in sediment geochemical dynamics is consistent with orbital control. In particular, sediment geochemical fluctuations reflect what appear to be orbitally forced changes in wind patterns and ocean circula...

View PDFchevron_right
Viaggi P. (2021) - Quantitative Impact of Astronomical and Sun-related Cycles on the Pleistocene Climate System from Antarctica Records
Paolo Viaggi

Quaternary Science Advances, 2021

We use the benefits of the full-resolution methodology for time-series decomposition singular spectrum analysis to assess the quantitative impact of orbital and, for the first time, millennial-scale Sun-related climate responses from EPICA records. The quantitative impact of the three Sun-related cycles (unnamed ~9.7-kyr; proposed 'Heinrich-Bond' ~6.0-kyr; Hallstatt ~2.5-kyr), cumulatively explain ~4.0% (δD), 2.9% (CO 2), and 6.6% (CH 4) in variance, demonstrating for the first time the minor role of solar activity in the regional budget of Earth's climate forcing. A cycle of ~3.6 kyr, which is little known in literature, results in a mean variance of 0.6% only, does not seem to be Sun-related, although a gravitational origin cannot be ruled out. According to the recurrence analysis of Heinrich events (6.03 ± 1.4 kyr) and their correlation with EPICA stack ~6.0-kyr cycle, it is proposed that this band of solar activity be named the 'Heinrich-Bond cycle'. On these basis, it is deemed that the 'Heinrich-Bond' solar cycle may act on the ice-sheet as an external instability factor both related to excess ice leading to calving process and IRD-layers ('cold-related' Heinrich events), and surface heating with meltwater streams ('warm-related' Heinrich events). The Hallstatt cycle is found in a number of solar proxies, geomagnetic secular variations, paleoclimatic oscillations, combination tones of Milankovitch forcings and resonant planetary beats, indicating an apparent 'multi-forcing' origin possibly related to planetary beat hypothesis. The orbital components consistently reflects the post-Mid-Pleistocene transition nature of the EPICA records in which the short eccentricity results in most of the variance (51.6%), followed by obliquity (19.0%) and precession (8.4%). Beyond the Milankovitch theory, evidence is emerging of a multiple-forcing cosmoclimatic system with stochastic interactions between external (gravitational resonances, orbitals, solar activity) and Earth's internal (geodynamics, atmosphere composition, feedback mechanisms) climate components, each having a strong difference in terms of the relative quantitative impact on Earth's climate.

View PDFchevron_right
Origin of the climatic cycles from orbital to sub-annual scales D.A. Stoykova, Y.Y. Shopov, D. Garbeva, L.T. Tsankov, C.J. Yonge (2008)
D. Garbeva, Yavor Shopov

We have confirmed the solar origin of insolation cycles of 11,500, 4400, 3950, 2770, 2500, 2090, 1960, 1670, 1460, 1280, 1195, 1145, 1034, 935, 835, 750 and 610 yrs found in speleothem luminescence by their presence in other indices of the solar wind. The 11,500-yr solar cycle can produce climatic variations similar to those caused by the orbital variations. We discovered a sub-annual cycle of 27 days in one very high-resolution speleothem proxy paleoclimatic record, attributed to solar rotation, which causes the periodic appearance of active zones on the visible solar surface, which are the major emitters of solar wind. Solar wind modulates cosmic ray flux at the Earth, while cosmic rays influence the atmospheric transparency, thus producing a multiplication of solar variations in insolation. Small variations of the solar activity can produce a measurable influence on insolation.

View PDFchevron_right
MILANKOVITCH CYCLES IN CLIMATE CHANGE, GEOLOGY AND GEOPHYSICS
Don Tarling

Proc. 6th International Symposium on Geophysics, Tanta, Egypt (2010), 1- 8, 2010

The strong correlation of the eccentricity, obliquity and precession changes in the Earth's orbit (Milankovitch cycles) with the proxy temperature indicators (principally δ 18 O) in continuous cores of sediment and ice, accumulated during the last 1-2 Myr, has led to a conclusion that climatic change is entirely a result of the fluctuations in the amount and latitudinal distribution of solar energy reaching the Earth's upper atmosphere, i.e. they are a result of 'solar forcing'. While a very good correlations exists for some Milankovitch spectra, there are misfits that suggest that the observed correlations may not be fully causative, i.e. some other related process is also involved that may be even more important. Furthermore, the temperature changes at the top of the atmosphere are small, relative to those of climatic changes, and so must be amplified by secondary effects, principally albedo changes resulting from changing snow and/or cloud cover. Spectral analyses of geological and geophysical properties in the absence of such secondary albedo processes, such as during the Cretaceous, have shown all Milankovitch periodicities are present in both gravitational and climatically related properties. Identical spectral peaks and ratios are also present in geomagnetic properties and sea-floor spreading rates of the same age. No other spectra are identified, but all Milankovitch frequenies are recorded. Such old seqences suggests that the climatic changes of the last 2 Myr should be similarly controlled by the distance and angular relationship with the Sun and Earth. It is suggested that current attribution of all terrestrial climatic change to only Milankovitch cycles in the Earth's orbit neglects the effects that changing plantetary orbits will have on the activity of the Sun. It is proposeded that dominant 100 kyr climatic cycle during the last 1-2 Myr is due to Jupiter's gravitational influence on the amount and quality of solar radiation being generated. This radiation is then modulated by the Earth's orbital behaviour.

View PDFchevron_right
Orbital tuning, eccentricity, and the frequency modulation of climatic precession
Oded Aharonson

Paleoceanography, 2010

1] The accuracy of geologic chronologies can, in principle, be improved through orbital tuning, the systematic adjustment of a chronology to bring the associated record into greater alignment with an orbitally derived signal. It would be useful to have a general test for the success of orbital tuning, and one proposal has been that eccentricity ought to covary with the amplitude envelope associated with precession variability recorded in tuned geologic records. A common procedure is to filter a tuned geologic record so as to pass precession period variability and compare the amplitude modulation of the resulting signal against eccentricity. There is a reasonable expectation for such a relationship to be found in paleoclimate records because the amplitude of precession forcing depends upon eccentricity. However, there also exists a relationship between eccentricity and the frequency of precession such that orbital tuning generates eccentricity-like amplitude modulation in filtered signals, regardless of the accuracy of the chronology or the actual presence of precession. This relationship results from the celestial mechanics governing eccentricity and precession and from the interaction between frequency modulation and amplitude modulation caused by filtering. When the eccentricity of Earth's orbit is small, the frequency of climatic precession undergoes large variations and less precession energy is passed through a narrow-band filter. Furthermore, eccentricity-like amplitude modulation is routinely obtained from pure noise records that are orbitally tuned to precession and then filtered. We conclude that the presence of eccentricity-like amplitude modulation in precession-filtered records does not support the accuracy of orbitally tuned time scales.

View PDFchevron_right
800,000 Years of Abrupt Climate Variability
Aaron Putnam

Science, 2011

View PDFchevron_right
Abrupt climate fluctuations not directly linked to astronomical causes and attributed to the reorganisation of atmosphere and ocean circulations.
Francesc Burjachs

Services fédéraux des Affaires Scientifiques, Techniques et Culturelles, Belgium., 1995

Final Report, december 1995, Research Contract GC/10/021. Programme d'Impulsion "Global Change" 1990-1996. Repport final / EINDVERSLAG. Programme d'Impulsion / Impulsprogramma / Global Change 1990-1996. Alacant; Elx; La Cruz grafica micrita; La Draga geoquímica ostracodes; Salines. Department of Geology, Université Catholique de Louvain, Louvain-la-Neuve, Belgium; ICTJA-CSIC. Barcelona, Catalonia.

View PDFchevron_right

References (45)

  1. Milankovic, M.: 1920, Théorie mathématique des Phénomènes thermiques produits par la radiation solaire, Académie Yougoslave des Sciences de Zagreb (Ed.), Paris: Gauthier Villars.
  2. Milankovic, M.: 1941, Kanon der Erdbestrahlung und seine Anwendung auf das Eiszeitenproblem, Belgrad:e Royal Serbian Sciences. (English translation Beograd 1998).
  3. Berger, A. L.: 1977, Support for astronomical theory of climatic change, Quat. Res., 269, 44-45.
  4. Berger, A. L.: 1978, Long-term variations of caloric insolation resulting from the Earth's orbital elements., Nature, 9, 139-167.
  5. Varadi, F., Runnegar, B., Ghil, M.: 2003, Successive refinements in long-term integrations of planetary orbits, Astrophys.. J., 592, 620-630 (2003).
  6. Hoffman, P. F., Abbot, D. S., Ashkenazy, Y., Benn, D. I., Brocks, J. J., Cohen, P. A., Cox, G. M., Creveling, J. R., Donnadieu, Y., Erwin, D. H., Fairchild, I. J., Ferreira, D., Goodman, J. C., Halverson, G. P., Jansen, M. F., Le Hir, G., Love, G. D., Macdonald, F. A., Maloof, A. C., Partin, C. A., Ramstein, G., Rose, B. E. J., Rose, C. V., Sadler, P. M., Tziperman, E., Voigt, A., Warren, S. G.: 2017, Snowball Earth climate dynamics and Cryogenian geology-geobiology, Sci. Adv., 3, e1600983.
  7. Hodell, D. A. Channell, J. E. T.: 2016, Mode transitions in Northern Hemisphere glaciation: co- evolution of millennial and orbital variability in Quaternary climate, Clim. Past, 12, 1805-1828.
  8. Ruddiman, W. F.: 1977, Late Quaternary deposition of ice) rafted sand in subpolar North-Atlantic (Lat 40-degrees to 65-degrees-N), Geol. Soc. Am. Bull., 88, 1813-1827.
  9. Broecker, W., Bond, G., Klas, M., Clark, E., McManus, J.: 1992, Origin of the northern Atlantic's Heinrich events. Clim. Dyn., 6, 265-273
  10. Bond, G., Heinrich, H., Broecker, W., Labeyrie, L., McManus, J., Andrews, J., Huon, S., Jantschik, R., Clasen, S., Simet, C., Tedesco, K., Klas, M., Bonani, G., Ivy, S.: 1992, Evidence for massive discharges of icebergs into the North Atlantic Ocean during the last glacial period, Nature, 360, 245- 249.
  11. Rasmussen, S. O., Bigler, M., Blockley, S. P., Blunier, T., Buchardt, S. L., Clausen, H. B., Cvijanovic, I., Dahl-Jensen, D., Johnsen, S. J., Fischer, H., Gkinis, V., Guillevic, M., Hoek, W. Z., Lowe, J. J., Pedro, J. B., Popp, T., Seierstad, I. K., Steffensen, J. P., Svensson, A. M., Vallelonga, P., Vinther, B. M., Walker, M. J. C., Wheatley, J. J., Winstrup, M.: 2à14, A stratigraphic framework for abrupt climatic changes during the Last Glacial period based on three synchronized Greenland ice-core records: refining and extending the INTIMATE event stratigraphy, Quat. Sci. Rev., 106, 14-28.
  12. Clark, P. U., Archer, D., Pollard, D., Blum, J. D., Rial, J. A., Brovkin, V., Mix, A. C., Pisias, N. G., Roy, M.: 2006, The middle Pleistocene transition: characteristics, mechanisms, and implications for long-term changes in atmospheric PCO 2 , Quat. Sci. Rev., 25, 3150-3184.
  13. Muttoni, G., Carcano, C., Garzanti, E., Ghielmi, M., Piccin, A., Pini, R., Rogledi, S., Sciunnach, D.: 2003, Onset of major Pleistocene glaciations in the Alps, Geology, 31, 989-992.
  14. Knudsen, M. F., Norgaard, J., Grischott, R., Kober, F., Egholm, D. L., Hansen, T. M., Jansen, J. D.: 2020, New cosmogenic nuclide burial-dating model indicates onset of major glaciations in the Alps during Middle Pleistocene Transition, Earth Planet. Sci. Lett., 549, 116491.
  15. Broecker, W. S.: 1994, Massive iceberg discharges as triggers for global climate change. Nature, 372, 421-424
  16. Rousseau, D.-D., Bagniewski, W., Ghil, M., 2021, Are abrupt climate changes related to the [Type here] astronomical theory? Clim. Past, submitted.
  17. Dansgaard, W., Johnsen, S. J., Moller, J., Langway, C. C.: 1969, One thousand centuries of climatic record from Camp Century on the Greenland ice sheet. Science, 166, 377-381
  18. Johnsen, S. J., Dansgaard, W., Clausen, H. B., Langway, C. C.: 1972, Oxygen isotope profiles through the Antartic and Greenland ice sheets. Nature, 235, 429-434.
  19. Dansgaard, W., Johnsen, S. J., Clausen, H. B., Dahi-Jensen, D., Gundestrup, N. S., Hammer, C. U., Hvidberg, C. S., Steffensen, J. P., Sveinbjöprnsdottir, A. E., Jouzel, J., Bond, G.: 1993, Evidence for general instability of past climate from a 250-kyr ice-core record. Nature, 364, 218-220
  20. Johnsen, S. J., Dahl-Jensen, D., Gundestrup, N., Steffensen, J. P., Clausen, H. B., Miller, H., Masson-Delmotte, V., Sveinbjörnsdottir, A. E., White, J.: 2001, Oxygen isotope and palaeotemperature records from six Greenland ice-core stations: Camp Century, Dye-3, GRIP, GISP2, Renland and NorthGRIP, J. Quat. Sci., 16, 299-307.
  21. Kindler, P., Guillevic, M., Baumgartner, M., Schwander, J., Landais, A., Leuenberger, M.: 2014, Temperature reconstruction from 10 to 120 kyr b2k from the NGRIP ice core, Clim. Past, 10, 887- 902.
  22. Wolff, E. W., Chappellaz, J., Blunier, T., Rasmussen, S. O., Svensson, A.: 2010, Millennial-scale variability during the last glacial: The ice core record, Quat. Sci. Rev., 29, 2828-2838.
  23. Rousseau, D.-D., Boers, N., Sima, A., Svensson, A., Bigler, M., Lagroix, F., Taylor, S., Antoine, P.: 2017, (MIS3 & 2) millennial oscillations in Greenland dust and Eurasian aeolian records -A paleosol perspective, Quat. Sci. Rev., 169, 99-113.
  24. Fletcher, W. J., Goni, M. F. S., Allen, J. R. M., Cheddadi, R., Combourieu-Nebout, N., Huntley, B., Lawson, I., Londeix, L., Magri, D., Margari, V., Mueller, U. C., Naughton, F., Novenko, E., Roucoux, K., and Tzedakis, P. C.: 2010, Millennial-scale variability during the last glacial in vegetation records from Europe, Quat. Sci. Rev., 29, 2839-2864.
  25. Henry, L. G., McManus, J. F., Curry, W. B., Roberts, N. L., Piotrowski, A. M., Keigwin, L. D.: 2016, North Atlantic ocean circulation and abrupt climate change during the last glaciation, Science, 353, 470-474.
  26. 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, 143-147.
  27. Sanchez-Goni, M. F., Turon, J. L., Eynaud, F., Gendreau, S.: 2000, European climatic response to millennial-scale changes in the atmosphere-ocean system during the last glacial period, Quat. Res., 54, 394-403.
  28. Sanchez-Goni, M. F., Cacho, I., Turon, J. L., Guiot, J., Sierro, F. J., Peypouquet, J. P., Grimalt, J. O., Shackleton, N. J.: 2002, Synchroneity between marine and terrestrial responses to millennial scale climatic variability during the last glacial period in the Mediterranean region, Clim. Dyn., 19, 95-105.
  29. Rousseau, D.-D., Antoine, P., Hatté, C., Lang, A., Zöller, L., Fontugne, M., Ben Othman, D., Luck, J. M., Moine, O., Labonne, M., Bentaleb, I., Jolly, D.: 2002, Abrupt millennial climatic changes from Nussloch (Germany) Upper Weichselian eolian records during the Last Glaciation, Quat. Sci. Rev., 21, 1577-1582.
  30. Rousseau, D.-D., Svensson, A., Bigler, M., Sima, A., Steffensen, J. P., Boers, N.: 2017, Eurasian contribution to the last glacial dust cycle: how are loess sequences built? Clim. Past, 13, 1181-1197.
  31. Rousseau, D.-D., Antoine, P., Sun, Y.: 2021, How dusty was the last glacial maximum over Europe? Quat. Sci. Rev., 254, 6775-6775.
  32. Waelbroeck, C., Labeyrie, L., Michel, E., Duplessy, J. C., McManus, J. F., Lambeck, K., Balbon, E., Labracherie, M.: 2002, Sea-level and deep water temperatures changes derived from benthic foraminifera isotopic records, Quat. Sci. Rev., 21, 295-305.
  33. MacAyeal, D. R.: 1993, Binge/Purge oscillations of the Laurentide ice-sheet as a cause of the North-Atlantics Heinrich events, Paleoceanography, 8, 775-784.
  34. Barker, S., Knorr, G., Edwards, R. L., Parrenin, F., Putnam, A. E., Skinner, L. C., Wolff, E., Ziegler, M.: 2011, 800,000 Years of Abrupt Climate Variability, Science, 334, 347-351.
  35. Wang, Y. J., Cheng, H., Edwards, R.L., An, Z.S., Wu, J.Y., Shen, C.C., Dorale, J.A.: 2001, A high- resolution absolute-dated Late Pleistocene monsoon record from Hulu Cave, China, Science. 294, 2345-2348 (2001).
  36. Rahmstorf, S.: 2002, Ocean circulation and climate during the past 120,000 years, Nature. 419, 207-214.
  37. Clark, P. U., Hostetler, S. W., Pisias, N. G., Schmittner, A., Meissner, K. J.: 2007, Mechanisms for an ~7-kyr climate and sea-level oscillation during marine isotope stage 3. in Ocean circulation: Mechanism and Impacts-Past and Future changes of Meridional Overturning, Eds. A. Schmittner, Chiang, J. C. H., and S. R. Hemming, AGU Monograph 173, 209-246.
  38. Blunier, T., Brook, E. J.: 2001, Timing of millennial-scale climate change in Antarctica and Greenland during the last glacial period, Science, 291, 109-112.
  39. Buizert, C., Adrian, B., Ahn, J., Albert, M., Alley, R. B., Baggenstos, D., Bauska, T. K., Bay, R. C., Bencivengo, B. B., Bentley, C. R., Brook, E. J., Chellman, N. J., Clow, G. D., Cole-Dai, J., Conway, H., Cravens, E., Cuffey, K. M., Dunbar, N. W., Edwards, J. S., Fegyveresi, J. M., Ferris, D. G., Fitzpatrick, J. J., Fudge, T. J., Gibson, C. J., Gkinis, V., Goetz, J. J., Gregory, S., Hargreaves, G. M., Iverson, N., Johnson, J. A., Jones, T. R., Kalk, M. L., Kippenhan, M. J., Koffman, B. G., Kreutz, K., Kuhl, T. W., Lebar, D. A., Lee, J. E., Marcott, S. A., Markle, B. R., Maselli, O. J., McConnell, J. R., McGwire, K. C., Mitchell, L. E., Mortensen, N. B., Neff, P. D., Nishiizumi, K., Nunn, R. M., Orsi, A. J., Pasteris, B., Pettit, E. C., Price, P. B., Priscu, J. C., Rhodes, R. H., Rosen, J. L., Schauer, A. J., Schoenemann, S. W., Sendelbach, P. J., Severinghaus, J. P., Shturmakov, A. J., Sigl, M., Slawny, K. R., Souney, J. M., Sowers, T. A., Spencer, M. K., Steig, E. J., Taylor, K. C., Twickler, M. S., Vaughn, B. H., Voigt, D. E., Waddington, E. D., Welten, K. C., Wendricks, A. W., White, J. W. C., Winstrup, M., Wong, G. J., Woodruff, T. E., Wais Divide Project Members: 2015, Precise interpolar phasing of abrupt climate change during the last ice age, Nature, 520, 661-665.
  40. Alley, R. B.: 1998, Palaeoclimatology -Icing the north Atlantic, Nature, 392, 336-337.
  41. Alley, R. B., Clark, P. U., Keigwin, L. D., Webb, R. S.: 1999, Making sense of millenial-scale climate change. in Mechanisms of global climate change at millenial time scales", Eds. P. U. Clark, R. Webb, et L. D. Keigwin, Geophysical Monograph. AGU, 385-394.
  42. Ghil, M., Childress, S.: 1987, Topics in Geophysical Fluid Dynamics: Atmospheric Dynamics, Dynamo Theory and Climate Dynamics, Springer-Verlag, New-York.
  43. Ghil, M., 1994, Cryothermodynamics: The chaotic dynamics of paleoclimate, Phys. D, 77, 130- 159.
  44. Ghil, M., Lucarini, V., 2020: The physics of climate variability and climate change, Rev. Mod. Phys., 92, 035002.
  45. Ghil, M. : 2021, Orbital insolation variations, intrinsic climate variability, and Quaternary glaciations. in One Hundred Years of Milanković's Theory of Climate Change, Proceedings of the Workshop Honoring the Milutin Milanković Jubilee, Ed. S. Maksimović, Milutin Milanković Association, Belgrade, in press.

Related papers

Abrupt climate changes and the astronomical theory
Michael Ghil

2021

Abrupt climate changes constitute a relatively new field of research, which addresses variations occurring in a relatively short time interval of tens to a hundred years. Such time scales do not correspond to the tens or hundreds of thousands of years that the astronomical theory of climate addresses. The latter theory involves parameters that are external to the climate system and whose multi-periodic variations are reliably known and 15 almost constant for a large extent of Earth history. Abrupt changes, conversely, appear to involve fast processes that are internal to the climate system; these processes varied considerably during the past 2.6 Myr, and yielded more irregular fluctuations. In this paper, we reexamine the main climate variations determined from the U1308 North Atlantic marine record, which yields a detailed calving history of the Northern Hemisphere ice sheets over the past 3.2 Myr. The magnitude and periodicity of the ice-rafted debris (IRD) 20 events observed in the U1308 record allow one to determine the timing of several abrupt climate changes, the larger ones corresponding to the massive iceberg discharges labeled Heinrich events (HEs). In parallel, abrupt warmings, called Dansgaard-Oeschger (DO) events, have been identified in the Greenland records of the last glaciation cycle. Combining the HE and DO observations, we study a complex mechanism that may lead to the observed millennial-scale variability corresponding to the abrupt climate changes of last 0.9 Myr. This 25 mechanism relies on amended Bond cycles, which group DO events and the associated Greenland stadials into a trend of increased cooling, with IRD events embedded into every stadial, the latest of these being an HE. These Bond cycles may have occurred during the last 0.9 Ma when Northern Hemisphere ice sheets reached their maximum extent and volume, thus becoming a major player in this time interval's climate dynamics. Since the waxing and waning of ice sheets during the Quaternary period are orbitally paced, we conclude that the 30 abrupt climate changes observed during the Mid and Upper Pleistocene are therewith indirectly linked to the astronomical theory of climate.

View PDFchevron_right
Astronomical theory of Paleoclimates and the last glacial-interglacial cycle☆
Andre Berger

Quaternary Science Reviews, 1992

In the 19th century, Croll and Pilgrim stressed the importance of severe winters as a cause of Quaternary ice ages. Later on, mainly during the first half of the 20th century, Kfppen, Spitaler and Milankovitch regarded high winter and low summer insolation as favoring glaciation. After Kfppen and Wegener related the Milankovitch new radiation curve to Penck and Briickner's subdivision of the Quaternary, there was a long lasting debate whether or not such changes in the insolation can explain the Quaternary glacial-interglacial cycles. In the 1970s, with the improvements of radiometric dating, and of acquiring and interpreting the long continuous geological records, with the advent of computers and with the development of more sophisticated astronomical and climate models, the astronomical theory and in particular its Milankovitch version were revived. Over the last 5 years, most geological, astronomical and climatological obstacles have been overcome and the causal role of the orbital variations in long-term variation of climate is taken almost universally for granted. Models of different categories of complexity, from conceptual ones to 3-D atmospheric general circulation models and 2-D time-dependent models of the whole climate system have now been astronomically forced in order to test the physical reality of the astronomical theory. For example, experiments with both low-and high-resolution GCMs show that the increased seasonality at 9,000 BP, leads to intensified summer monsoon circulation of Africa and southern Asia. On the other hand, seasonal models for simulating the transient response of the climate system to astronomical forcing are also developed and the output of these most recent modeling efforts compares favorably with data of the past 400,000 years. Accordingly, the model predictions for the next 100,000 years are used as a basis for forecasting how climate would evolve when forced by orbital variations in the absence of anthropogenic disturbances: the long-term cooling trend which began some 6,000 years ago will continue for the next 5,000 years, this first temperature minimum will be followed by an amelioration around 15,000 AP (after present), by a cold interval centered at 23,000 AP, and by a major glaciation at around 60,000 AP.

View PDFchevron_right
The Climate Response to the Astronomical Forcing
Andre Berger

Space Science Reviews, 2007

Links between climate and Earth's orbit have been proposed for about 160 years. Two decisive advances towards an astronomical theory of palaeoclimates were Milankovitch's theory of insolation (1941) and independent findings, in 1976, of a double precession frequency peak in marine sediment data and from celestial mechanics calculations. The present chapter reviews three essential elements of any astronomical theory of climate: (1) to calculate the orbital elements, (2) to infer insolation changes from climatic precession, obliquity and eccentricity, and (3) to estimate the impact of these variations on climate. The Louvain-la-Neuve climate-ice sheet model has been an important instrument for confirming the relevance of Milankovitch's theory, but it also evidences the critical role played by greenhouse gases during periods of low eccentricity. It is recognised today that climatic interactions at the global scale were involved in the processes of glacial inception and deglaciation. Three examples are given, related to the responses of the carbon cycle, hydrological cycle, and the terrestrial biosphere, respectively. The chapter concludes on an outlook on future research directions on this topic.

View PDFchevron_right
Variations in the Earth's Orbit: Pacemaker of the Ice Ages
James Hays

Science, 1976

For more than a century the cause of fluctuations in the Pleistocene ice sheets has remained an intriguing and unsolved scientific mystery. Interest in this problem has generated a number of possible explanations (1, 2). One group of theories invokes factors external to the climate system, including variations in the output of the sun, or the amount of solar energy reaching the earth caused by changing concentrations of interstellar dust (3); the seasonal and latitudinal distribution of incoming radiation caused by changes in the earth's orbital geometry (4); the volcanic dust content of the atmosphere (5); and the earth's magnetic field (6). Other theories are based on internal elements of the system believed to have response times sufficiently long to yield fluctuations in the range 104 to 106 years. Such features include the growth and decay of ice sheets (7), the surging of the Antarctic ice sheet (8); the ice cover of the Arctic Ocean (9); the distribution of carbon dioxide between atmosphere and ocean (10); and the deep circulation of the ocean (11). Additionally, it has been argued that as an almost intransitive system, climate could alternate between different states on an appropriate time scale without the intervention of any external stimulus or internal time constant (12). Among these ideas, only the orbital 10 DECEMBER 1976 SC:I E:NC E the last interglacial on the basis of these curves have ranged from 80,000 to 180,000 years ago (22). The second and more critical problem in testing the orbital theory has been the uncertainty of geological chronology. Until recently the inaccuracy of dating methods limited the interval over which a meaningful test could be made to the last 150,000 years. Hence the most convincing arguments advanced in support of the orbital theory to date have beenbased on the ages of 80,000, 105,000, and 125,000 years obtained for coral terraces first on Barbados (15) and later on New Guinea (23) and Hawaii (24). These structures record episodes of high sea level (and therefore low ice volume) at times predicted by the Milankovitch theory. Unfortunately, dates for older terraces are too uncertain to yield a definitive test (25). More climatic information is provided by the continuous records from deep-sea cores, especially the oxygen isotope record obtained by Emiliani (26). However, the quasi-periodic nature of both the isotopic and insolation curves, and the uncertain chronology of the older geologic records, have combined to render plausible different astronomical interpretations of the same geologic data (13, 14, 17, 27). Strategy All versions of the orbital hypothesis of climatic change predict that the obliquity of the earth's axis (with a period of about 41,000 years) and the precession of the equinoxes (period of about 21,000 years) are the underlying, controlling variables that influence climate through their impact on planetary insolation. Most of these hypotheses single out The authors are all members of the CLIMAP project. J.

View PDFchevron_right
Astronomical forcing of sub-Milankovitch climate oscillations during the late Quaternary
Alison Kelsey

A climate signal of ~1500-yr quasi-periodicity (e.g., Bond events) has been found from the Arctic to Antarctica, in palaeoclimatic data derived from a range of environmental proxy records. Solar and lunar forcing have individually been suggested as the cause of this millennial-scale signal, although some contend that it is little more than stochastic resonance within the climate system. Also debated is whether this climate signal is forced by the ocean-atmosphere dynamics of the North Atlantic or the tropical Pacific, as well as relevant climatic teleconnections. The cause of this cycle is elusive as no known solar cycle of this length exists, whilst forcing due to lunar gravitation has been dismissed as being too weak. The most likely cause of any periodic climate signal is an astronomical one, as demonstrated in Milankovitch cycles. This thesis explores a potential astronomical cause of millennial-and centennial-scale periodicities and variability, based on a combination of solar and lunar forcing. Conceptual and trigonometric models, physical models of insolation, solar irradiance, and gravitation, and astronomical data were used in this exploration. Identified as a possible cause of the ~1500-yr climate cycle is precession. Precession changes the timing of Earth's seasons relative to our calendar and external reference points, such as the fixed stars and the closest point in Earth's orbit to the Sun (the perihelion). The primary actors in precession are the Sun and Moon through their gravitational influence on the rotating Earth. Significant climatic impacts of precession are seen in the ~21-ky Milankovitch precessional cycle, the result of two interacting precessional cycles: equinoctial (associated with the seasonal/tropical year) and apsidal (associated the perihelion and anomalistic year). This thesis investigates precession at a high-frequency scale, enabling a more detailed tracking of the moving seasons relative to the moving perihelion at sub-Milankovitch scales throughout the last 5,500 yrs. This research found a statistically-significant, strong positive correlation between solar insolation reconstruction derived from Antarctic 10 Be ice-core data and a normalised, chronologically-anchored model of superimposed astronomical cycles that emulates the ~1500-yr climate cycle. Pronounced millennial-scale signals were observed in Earth-Moon distances and gravitation data. Maximum forcing occurs at perihelion, close to lunar perigee and Bond events occur at these points during the range of the astronomical data. Previously identified potential components of the ~1500-yr climate signal, viz the 209-yr Suess de Vries cycle and a 133-yr cycle, can be clearly seen in the astronomical and physical data. Modelled, highfrequency, perigee-perihelion interaction by this research reinforces these results, reproducing and explaining the variability of millennial-scale climate signals. Such variability is also supported through the movement relative to the tropical year, in conjunction with mapping of Metonic lunation and perihelion positions. iii Supported by multiple lines of evidence, the results of this thesis suggest that the Sun and Moon act together through gravitation and insolation to produce millennial-, centennial-and decadal-scale climate signals through tidal forcing of Earth's atmosphere and ocean. Key mechanisms and components are precession, perihelion, perigee, lunation, and nutation (wobble of Earth's axis). Key inferences from these results are that astronomical forcing influences radiocarbon chronological variability, such as marine reservoir values, variability and time lag in radiocarbon data, and also suggest that the 209-yr SdV cycle is caused by combined solar and lunar forcing rather than previously inferred solar variability.

View PDFchevron_right

Related topics

  • Dansgaard-Oeschger events
  • Ice Sheets
    • 580 California St., Suite 400
    San Francisco, CA, 94104
    © 2025 Academia. All rights reserved