Fon: +49-421-218-65444
Fax: +49-421-218-65454
E-Mail: mschulz@marum.de

For further information on our research see:

Geosystem Modeling Group Homepage
DFG-Research Center / Excellence Cluster The Ocean in the Earth System - Research Area Ocean and Climate

Research Interests:

1. Using numerical models of varying complexity to study

- the origin of climate variations at millennial-to-interdecadal timescales,
- marine ecosystems and global biogeochemical cycles during the Neogene,
- the role of oceanic gateways in Neogene climate evolution and
- Milankovitch climate variations in icehouse and greenhouse worlds.

2. Software development for time-series analysis of unevenly spaced data.

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Publications:

2010  2009  2008  2007  2006  2005  2004  2003  2002  2001  2000 and before

2010

Merkel, U., Prange, M. and Schulz, M. (2010): ENSO variability and teleconnections during glacial climates. Quaternary Science Reviews, 29, 86-100. Reprint

Timmermann, A., Menviel, L., Okumura, Y., Schilla, A., Merkel, U., Timm, O., Hu, A., Otto-Bliesner, B. and Schulz, M. (2010): The bipolar seesaw revisited. Quaternary Science Reviews, 29, 74-85. Reprint

Prange, M., J. Jongma, and M. Schulz (2010): Centennial-to-millennial-scale Holocene climate variability in the North Atlantic region induced by noise. In: Stochastic Physics and Climate Modelling, edited by: Palmer, T. and Williams, P., Cambridge University Press, 307-326. Reprint

2009

Niedermeyer, E. M., Prange, M., Mulitza, S., Mollenhauer, G., Schefuß, E. and Schulz, M. (2009): Extratropical forcing of Sahel aridity during Heinrich stadials. Geophys. Res. Lett., 36, L20707, doi:10.1029/2009GL039687. Reprint

Langebroek, P., A. Paul, and M. Schulz (2009): Antarctic ice-sheet response to atmospheric CO₂ and insolation in the Middle Miocene. Climate of the Past, 5, 633-646. Reprint

Fraile, I., Schulz, M., Mulitza, S., Merkel, U., Prange, M. and Paul, A. (2009): Modeling the seasonal distribution of planktonic foraminifera during the Last Glacial Maximum. Paleoeceanography, 24, PA2216, doi:10.1029/2008PA001686. Reprint

Fraile, I., S. Mulitza, and M. Schulz (2009): Modeling planktonic foraminiferal seasonality: Implications for sea-surface temperature reconstructions. Marine Micropaleontology, 72, 1-9. Reprint

Jones, P. D., K. R. Briffa, T. J. Osborn, J. M. Lough, T. D. v. Ommen, B. M. Vinther, J. Luterbacher, E. R. Wahl, F. W. Zwiers, M. E. Mann, G. A. Schmidt, C. M. Ammann, B. M. Buckley, K. M. Cobb, J. Esper, H. Goosse, N. Graham, E. Jansen, T. Kiefer, C. Kull, M. Küttel, E. Mosley-Thompson, J. T. Overpeck, N. Riedwyl, M. Schulz, A. W. Tudhope, R. Villalba, H. Wanner, E. Wolff, and E. Xoplaki (2009): High-resolution paleoclimatology of the last millennium: a review of current status and future prospects. The Holocene, 19, 3-49. Reprint

2008

Mulitza, S., M. Prange, J.-B. W. Stuut, M. Zabel, T. von Dobeneck, A. C. Itambi, J. Nizou, M. Schulz, and G. Wefer (2008): Sahel megadroughts triggered by glacial slowdowns of Atlantic meridional overturning. Paleoceanography, 23, PA4206, doi:10.1029/2008PA001637. Reprint

Franke, J., M. Schulz, A. Paul, and J. Adkins (2008): Assessing the Ability of the ¹⁴C Projection-Age Method to Constrain the Circulation of the Past in a 3D Ocean Model. Geochem. Geophys. Geosys., 9, Q08003, doi:10.1029/2008GC001943. Reprint

Franke, J., A. Paul, and M. Schulz (2008): Modeling variations of marine reservoir ages during the last 45,000 years. Clim. Past, 4, 125-136. Reprint / Supplementary Material / Online Reservoirage Database

Fraile, I., M. Schulz, S. Mulitza, and M. Kucera (2008): Predicting the global distribution of planktonic foraminifera using a dynamic ecosystem model. Biogeosciences, 5, 891-911. Reprint

2007

Holbourn, A., W. Kuhnt, M. Schulz, J.-A. Flores and N. Andersen (2007): Orbitally-paced climate evolution during the middle Miocene "Monterey" carbon-isotope excursion. Earth Planet. Sci. Lett., 261, 534-550. Reprint

Jongma, J. I., M. Prange, H. Renssen, and M. Schulz (2007): Amplification of Holocene multicentennial climate forcing by mode transitions in North Atlantic overturning circulation. Geophysical Res. Lett., 34, L15706, doi:10.1029/2007GL030642. Reprint / Supplementary Material

Schulz, M., Prange, M., and A. Klocker (2007): Low-frequency oscillations of the Atlantic Ocean meridional overturning circulation in a coupled climate model. Climate of the Past, 3, 97-107. Reprint

2006

Steph, S., R. Tiedemann, M. Prange, J. Groeneveld, D. Nürnberg, L. Reuning, M. Schulz, and G. Haug (2006): Changes in Caribbean surface hydrography during the Pliocene shoaling of the Central American Seaway. Paleoceanography, 21, PA4221, doi:10.1029/2004PA001092. Reprint

Sima, A., A. Paul, M. Schulz and H. Oerlemans (2006): Modeling the oxygen-isotopic composition of the North American Ice Sheet and its effect on the isotopic composition of the ocean during the last glacial cycle. Geophys. Res. Lett., 33, L15706, doi:10.1029/2006GL026923. Reprint / Supplementary Material

Zaric, S., Schulz, M. and Mulitza, S. (2006): Global prediction of planktic foraminiferal fluxes from hydrographic and productivity data. Biogeosciences, 3, 187-207. Reprint

2005

Holbourn, A., Kuhnt, W., Schulz, M. and Erlenkeuser, E. (2005): Impacts of orbital forcing and atmospheric carbon dioxide on Miocene ice-sheet expansion. Nature, 438, 483-487. Reprint / Supplementary Material

Beckmann, B., Flögel, S., Hofmann, P., Schulz, M. and Wagner, T. (2005): Orbital forcing of Cretaceous river discharge in tropical Africa and ocean response. Nature, 437, 241-244. Reprint / Supplementary Material

Klocker, A., M. Prange and M. Schulz (2005): Testing the influence of the Central American Seaway on orbitally forced northern hemisphere glaciation. Geophys. Res. Lett., 32(3), L03703, 10.1029/2004GL021564. Reprint

Jiang, H., J. Eiriksson, M. Schulz, K.-L. Knudsen and M. S. Seidenkrantz (2005): Evidence for solar forcing of sea-surface temperature on the North Icelandic shelf during the late Holocene. Geology, 33, 73-76. Reprint

2004

Holbourn, A., W. Kuhnt, and M. Schulz (2004): Orbitally paced climate variability during the middle Miocene: High-resolution benthic stable isotope records from the tropical western Pacific. In Continent-ocean interactions within east Asian marginal seas, edited by Clift, P., W. Kuhnt, P. Wang and D. Hayes, pp. 321-337, American Geophysical Union, Washington DC. Reprint

Schulz, M., Paul, A. and Timmermann, A. (2004): Glacial-Interglacial Contrast in Climate Variability at Centennial-to-Millennial Timescales: Observations and Conceptual Model. Quat. Sci. Rev., 23, 2219-2230. Reprint

Prange, M. and M. Schulz (2004): A coastal upwelling-seesaw in the Atlantic Ocean as a result of the closure of the Central American Seaway. Geophys. Res. Lett., 31(17), L17207, 10.1029/2004GL020073. Reprint / Accompanying Pages Newsletter Article

Sima, A., A. Paul and M. Schulz (2004): The Younger Dryas -- an intrinsic feature of late Pleistocene climate change at millennial timescales. Earth Planet. Sci. Lett., 222, 741-750. Reprint

Schulz, M. and Paul, A. (2004): Sensitivity of the ocean-atmosphere carbon cycle to ice-covered and ice-free conditions in the Nordic Seas during the Last Glacial Maximum. Palaeogeography, Palaeoclimatology, Palaeoecology, 207,127-141. Reprint

2003

Sarnthein, M., van Kreveld, S., Erlenkeuser, H., Grootes, P.M., Kucera, M., Pflaumann, U. and Schulz, M. (2003): Centennial-to-millennial-scale periodicities of Holocene climate and sediment injections off the western Barents shelf, 75°N. Boreas, 32, 447-461. Reprint

Pahnke, K., R. Zahn, H. Elderfield and M. Schulz (2003): 340,000 Year centennial-scale marine record of southern hemisphere climatic oscillation. Science, 301, 948-952. Reprint / Supplementary Material

Timmermann, A., Gildor, H., Schulz, M. and Tziperman, E. (2003): Coherent resonant millennial-scale climate oscillations triggered by massive meltwater pulses. Journal of Climate, 16, 2569-2585. Reprint

2002

Schulz, M., Paul, A. and Timmermann, A. (2002): Relaxation oscillators in concert: A framework for climate change at millennial timescales during the late Pleistocene. Geophys. Res. Lett., 29 (24), 10.1029/2002GL016144. Reprint

Kiefer, T., Lorenz, S., Schulz, M., Lohmann, G., Sarnthein, M. and Elderfield, H. (2002): Response of precipitation over Greenland and the adjacent ocean to North Pacific warm spells during Dansgaard-Oeschger stadials. Terra Nova, 14, 295-300. Reprint

Schulz, M. (2002): On the 1470-year pacing of Dansgaard-Oeschger warm events. Paleoceanogr., 17 (3), 10.1029/2000PA000571. Reprint

Schulz, M. and Mudelsee, M. (2002): REDFIT: estimating red-noise spectra directly from unevenly spaced paleoclimatic time series. Comput. Geosci., 28, 421-426. Reprint / download programm

Schulz, M. (2002): The tempo of climate change during Dansgaard-Oeschger interstadials and its potential to affect the manifestation of the 1470-year climate cycle. Geophys. Res. Lett., 29 (1), 10.1029/2001GL013277. Reprint

Schulz, M. and Paul, A. (2002): Holocene climate variability on centennial-to-millennial time scales: 1. Climate records from the North-Atlantic realm. In: Wefer, G., Berger, W. H., Behre, K.-E. and Jansen, E. (eds.), Climate development and history of the North Atlantic Realm. Springer Verlag, Berlin, 41-54. Reprint

Paul, A. and Schulz, M. (2002): Holocene climate variability on centennial-to-millennial time scales: 2. Internal feedbacks and external forcings as possible causes. In: Wefer, G., Berger, W. H., Behre, K.-E. and Jansen, E. (eds.), Climate development and history of the North Atlantic Realm. Springer Verlag, Berlin, 55-73. Reprint

Schulz, M., Berger, W. H., Baillie, M., Luterbacher, J., Meincke, J., Negendank, J. F. W., Paul, A. and Ramseier, R. O. (2002): Tracing climate-variability: the search for climate dynamics on decadal to millennial time scales. In: Wefer, G., Berger, W. H., Behre, K.-E. and Jansen, E. (eds.), Climate development and history of the North Atlantic Realm. Springer Verlag, Berlin, 125-148. Reprint

Hinnov, L. A., Schulz, M. and Yiou, P. (2002): Interhemispheric space-time attributes of the Dansgaard-Oeschger oscillations between 100 and 0 ka. Quat. Sci. Rev., 21, 1213-1228. Reprint / Supplementary Material

Helmke, J. P., Schulz, M. and Bauch, H. A. (2002): Sediment-color record from the northeast Atlantic reveals patterns of millennial-scale climate variability during the past 500,000 years. Quat. Res., 57, 49-57. Reprint

2001

Sarnthein, M., Stattegger, K., Dreger, D., Erlenkeuser, H., Grootes, P., Haupt, B. J., Jung, S., Kiefer, T., Kuhnt, W., Pflaumann, U., Schäfer-Neth, C., Schulz, H., Schulz, M., Seidov, D., Simstich, J., van Kreveld, S., Vogelsang, E., Völker, A. and Weinelt, M. (2001): Fundamental modes and abrupt changes in North Atlantic circulation and climate over the last 60 ky - Concepts, reconstructions and numerical modeling. In: Schäfer, P., Ritzrau, W., Schlüter, M. and Thiede, J. (eds.), The Northern North Atlantic: A changing environment. Springer Verlag, Berlin, 365-410. Reprint

Schulz, M., Seidov, D., Sarnthein, M. and Stattegger, K. (2001): Modeling ocean-atmosphere carbon budgets during the Last Glacial Maximum - Heinrich 1 Meltwater Event - Bølling transition. Int. Journ. Earth Sciences, 90, 412-425. Reprint

2000 and before

Lohmann, G. and Schulz, M. (2000): Reconciling Bølling warmth with peak deglacial meltwater discharge. Paleoceanogr., 15, 537-540. Reprint

Hay, W. W., DeConto, R. M., Wold, C. N., Wilson, K. M., Voigt, S., Schulz, M., Rossby-Wold, A., Dullo, W.-C., Ronov, A. B., Balukhovsky, A. N. and Söding, E. (1999): Alternative global Cretaceous paleogeography. In: Barrera, E. and Johnson, C. C. (eds.), Evolution of the Cretaceous ocean-climate system, Special Paper, 332. Geol. Soc. Amer., Boulder, 1-47. Reprint

Schulz, M., Berger, W. H., Sarnthein, M. and Grootes, P. M. (1999): Amplitude variations of 1470-year climate oscillations during the last 100,000 years linked to fluctuations of continental ice mass. Geophys. Res. Lett., 26, 3385-3388. Reprint

Mudelsee, M. and Schulz, M. (1997): The Mid-Pleistocene climate transition: onset of 100 ka cycle lags ice volume build-up by 280 ka. Earth Planet. Sci. Lett., 151, 117-123. Reprint

Schulz, M. and Stattegger, K. (1997): SPECTRUM: Spectral analysis of unevenly spaced paleoclimatic time series. Comput. Geosci., 23, 929-945. Reprint / download program

Schulz, M. and Schäfer-Neth, C. (1997): Translating Milankovitch climate forcing into eustatic fluctuations via thermal deep water expansion: a conceptual link. Terra Nova, 9, 228-231. Reprint

Schulz, M., Wold, C. N., Ronov, A. B. and Hay, W. W. (1995): A forward and inverse transformation program for the 'Atlas of Lithological-Palaeogeographical Maps of the World'. Comput. Geosci, 21, 907-911. Reprint / download program

Schulz, M., Mudelsee, M. and Wolf-Welling, T. C. W. (1994): Fractal analyses of Pleistocene marine oxygen isotope records. In: Kruhl, J. H. (ed.), Fractals and dynamic systems in geosciences. Springer Verlag, Berlin, 307-317. Reprint

Pollard, D. and Schulz, M. (1994): A model for the potential locations of Triassic evaporite basins driven by paleoclimatic GCM simulations. Glob. Planet. Change, 9, 233-249. Reprint

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Articles in press/submitted:

Steph, S., R. Tiedemann, M. Prange, J. Groeneveld, M. Schulz, A. Timmermann, D. Nürnberg, C. Saukel, and G. H. Haug (in press): Early Pliocene increase in thermohaline overturning preconditioned the development of the modern equatorial Pacific cold tongue. Paleoceanography.

Langebroek, P., A. Paul, A. and M. Schulz (submitted): Simulating the sea-level imprint on marine oxygen-isotope records during the Middle Miocene using an ice sheet-climate model.

Prange, M., S. Steph, M. Schulz, and L. Keigwin (submitted): Inferring moisture transport across Central America: Can modern analogs of climate variability help reconcile paleosalinity records?

Johnstone, H. J. H., M. Schulz, J. Yu, and H. Elderfield (submitted): Inside story: An X-ray microtomography method for assessing dissolution in foraminifera tests.

Johnstone, H. J. H., J. Yu, H. Elderfield, and M. Schulz (submitted): Calibrating X-ray computed tomography based dissolution index (XDX) to dissolution bias of Mg/Ca in planktonic foraminifera.

Johnstone, H. J. H., W. Lee, T. Kiefer, M. Schulz, and H. Elderfield (submitted): Effect of preservation state of planktonic foraminifera tests on the decrease in Mg/Ca due to reductive cleaning and on analytical yield.

Felis, T., U. Merkel, R. Asami, P. Deschamps, E. C. Hathorne, M. Kölling, E. Bard, G. Cabioch, N. Durand, M. Prange, M. Schulz, S. Y. Cahyarini, and M. Pfeiffer (submitted): Enhanced El Niño-Southern Oscillation variability at the end of the last glacial.

Berger, W. H., Schulz, M. and Wefer, G. (submitted): Quaternary Oceans and Climate Change: Lessons for the Future?

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Software:

SPECTRUM: Spectral analysis of unevenly spaced time series

A menu-driven PC program that allows the analysis of unevenly spaced time series in the frequency domain. The program is based on the Lomb-Scargle Fourier transform for unevenly spaced data in combination with the Welch-Overlapped-Segment-Averaging procedure. SPECTRUM can perform: 1) harmonic analysis (detection of periodic signal components), 2) spectral analysis of single time series and 3) cross-spectral analysis (cross-amplitude-, coherency- and phase-spectrum). Cross-spectral analysis does not require a common time axis of the two processed time series. 4) Analytical results are supplemented by statistical parameters that allow the evaluation of the results. During the analysis a user is guided by a variety of messages. 5) Results are displayed graphically and can be saved as plain ASCII or PCX files. 6) Additional tools for visualizing time series data and sampling intervals, integrating spectra and measuring phase angles facilitate the analysis. Compared to the widely used Blackman-Tukey approach for spectral analysis of paleoclimatic data, the advantage of SPECTRUM is the avoidance of any interpolation of the time series.

Version 2.2: Binaries for DOS/Win9x,

       Borland Pascal source code
      (Make sure to keep the directory structure when unzipping.)
       Documentation as pdf

 REDFIT: Red-noise spectra directly from unevenly spaced time series

Paleoclimatic time series are commonly unevenly spaced in time, making it difficult to obtain an accurate estimate of their typical red-noise spectrum. This Fortran 90 program overcomes this problem by fitting a first-order autoregressive (AR1) process, being characteristic for many climatic processes, directly to unevenly spaced time series. Hence, interpolation in the time domain and its inevitable bias can be avoided. The program can be used to test if peaks in the spectrum of a time series are significant against the red-noise background from an AR1 process.

Version 3.8c (August 2009) : Binaries for Win2000/XP/Win7, Fortran 90 source code and documentation (Make sure to keep the directory structure when unzipping.)

New in version 3.8: Rare crashes for time series with near-zero persistence fixed.
New in version 3.7: Automatic check of input data added. If the program encounters decreasing ages it will stop. Identical age entries and the corresponding data values are automatically averaged.

A graphical user interface is now available for REDFIT. It was developed by Boris Priehs (Univ. Bremen) and uses the commercial software MATLAB (Version 7 or above) to easily control the settings of REDFIT and to visualize the results: MATLAB script files and documentation.

ENVELOPE: Envelope estimation from unevenly spaced time series

This program estimates temporal changes in amplitude (= signal envelope) and phase of a signal component of given period in a time series. The program can process unevenly spaced input data directly, that is, without the requirement of interpolation.

Version 5.3 (September 2004): Binaries for DOS/Win9x/NT/2000 and documentation.

New in version 5.3: Automatic check of input data added. If the program encounters decreasing ages it will stop. Identical age entries and the corresponding data values are automatically averaged.

TIMEFRQ: Time-frequency analysis of unevenly spaced time series

This program estimates temporal amplitude changes of sinusoidal signal components in a given time series over a prescribed frequency range (spectrogram). The program can process unevenly spaced input data directly, that is, without the requirement of interpolation.

Version 4.3 (July 2004): Binaries for DOS/Win9x/NT/2000 and documentation.

New in version 4.3: Automatic check of input data added. If the program encounters decreasing ages it will stop. Identical age entries and the corresponding data values are automatically averaged.