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The Medieval Warm Period and Little Ice Age in the Eastern Mediterranean
Schilman, B., Bar-Matthews, M., Almogi-Labin, A. and Luz, B.  2001.  Global climate instability reflected by Eastern Mediterranean marine records during the late Holocene.  Palaeogeography, Palaeoclimatology, Palaeoecology 176: 157-176.

What was done
The authors analyzed foraminiferal oxygen and carbon isotopes and the physical and geochemical properties of sediments contained in two cores extracted from the bed of the southeastern Mediterranean Sea off the coast of Israel.

What was learned
The authors note that "late Holocene climatic instability was clearly demonstrated" by their high-resolution study.  Over the past millennium, they make particular mention of two extreme climatic events: one centered at about1200 AD, which they describe as "the Medieval Warm Period (MWP) global climatic event," and one centered at about 1730, which they describe as "the cooling global event known as the Little Ice Age."

What it means
In discussing their findings, the authors note there is an abundance of other evidence for the existence of the Medieval Warm Period in the Eastern Mediterranean, including "high Saharan lake levels (Schoell, 1978; Nicholson, 1980), high Dead Sea levels (Issar et al., 1989, 1991; Issar, 1990, 1998; Issar and Makover-Levin, 1996), and high levels of the Sea of Galilee (Frumkin et al., 1991; Issar and Makover-Levin, 1996)," as well as "a precipitation maximum at the Nile headwaters (Bell and Menzel, 1972; Hassan, 1981; Ambrose and DeNiro, 1989) and in the northeastern Arabian Sea (von Rad et al., 1999)."  In addition, they remark that their Little Ice Age data paint a picture of "the coldest conditions prevailing in the SE Mediterranean during the past 3.6 ka [3600 years]."

The evidence for a global Medieval Warm Period and a global Little Ice Age keeps getting stronger by the day (see both headings in our Subject Index).  Clearly, the Intergovernmental Panel on Climate Change should never have abandoned their original climate history of the world - which accurately depicted these significant climatic excursions (Houghton et al., 1990) - in favor of the flawed "hockey stick" plot of Mann et al. (1998, 1999).

Ambrose, S.H. and DeNiro, M.J.  1989.  Climate and habitat reconstruction using stable carbon and nitrogen isotope ratios of collagen in prehistoric herbivore teeth from Kenya.  Quaternary Research 31: 407-422.

Bell, B. and Menzel, D.H.  1972.  Toward the observation and interpretation of solar phenomena.  AFCRL F19628-69-C-0077 and AFCRL-TR-74-0357, Air Force Cambridge Research Laboratories, Bedford, MA, pp. 8-12.

Frumkin, A., Magaritz, M., Carmi, I. and Zak, I.  1991.  The Holocene climatic record of the salt caves of Mount Sedom, Israel.  Holocene 1, 191-200.

Hassan, F.A.  1981.  Historical Nile floods and their implications for climatic change.  Science 212: 1142-1145.

Houghton, J.T., Jenkins, G.J. and Ephraums, J.J. (Eds.)  1990.  Climate Change: The IPCC Scientific Assessment.  Cambridge University Press, Cambridge, UK.

Issar, A.S.  1990.  Water Shall Flow from the Rock.  Springer, Heidelberg, Germany.

Issar, A.S.  1998.  Climate change and history during the Holocene in the eastern Mediterranean region.  In: Issar, A.S. and Brown, N. (Eds.), Water, Environment and Society in Times of Climate Change, Kluwer Academic Publishers, Dordrecht, The Netherlands, pp. 113-128.

Issar, A.S. and Makover-Levin, D.  1996.  Climate changes during the Holocene in the Mediterranean region.  In: Angelakis, A.A. and Issar, A.S. (Eds.), Diachronic Climatic Impacts on Water Resources with Emphasis on the Mediterranean Region, NATO ASI Series, Vol. I, 36, Springer, Heidelberg, Germany, pp. 55-75.

Issar, A.S., Tsoar, H. and Levin, D.  1989.  Climatic changes in Israel during historical times and their impact on hydrological, pedological and socio-economic systems.  In: Leinen, M. and Sarnthein, M. (Eds.), Paleoclimatology and Paleometeorology: Modern and Past Patterns of Global Atmospheric Transport, Kluwer Academic Publishers, Dordrecht, The Netherlands, pp. 535-541.

Issar, A.S., Govrin, Y., Geyh, M.A., Wakshal, E. and Wolf, M.  1991.  Climate changes during the Upper Holocene in Israel.  Israel Journal of Earth-Science 40: 219-223.

Mann, M.E., Bradley, R.S. and Hughes, M.K.  1998.  Global-scale temperature patterns and climate forcing over the past six centuries.  Nature 392: 779-787.

Mann, M.E., Bradley, R.S. and Hughes, M.K.  1999.  Northern Hemisphere temperatures during the past millennium: Inferences, uncertainties, and limitations.  Geophysical Research Letters 26: 759-762.

Nicholson, S.E.  1980.  Saharan climates in historic times.  In: Williams, M.A.J. and Faure, H. (Eds.), The Sahara and the Nile, Balkema, Rotterdam, The Netherlands, pp. 173-200.

Schoell, M.  1978.  Oxygen isotope analysis on authigenic carbonates from Lake Van sediments and their possible bearing on the climate of the past 10,000 years.  In: Degens, E.T. (Ed.), The Geology of Lake Van, Kurtman.  The Mineral Research and Exploration Institute of Turkey, Ankara, Turkey, pp. 92-97.

von Rad, U., Schulz, H., Riech, V., den Dulk, M., Berner, U. and Sirocko, F.  1999.  Multiple monsoon-controlled breakdown of oxygen-minimum conditions during the past 30,000 years documented in laminated sediments off Pakistan.  Palaeogeography, Palaeoclimatology, Palaeoecology 152: 129-161.

Reviewed 20 March 2002