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The Little Ice Age and Medieval Warm Period in Inner Mongolia
Reference
Jin, Z., Wu, J., Cao, J., Wang, S., Shen, J., Gao, N. and Zou, C.  2004.  Holocene chemical weathering and climatic oscillations in north China: evidence from lacustrine sediments.  Boreas 33: 260-266.

What was done
The authors analyzed percent organic carbon and Rb/Sr ratios in a sediment core extracted from the deepest part of Daihai Lake (11232'-11248'E, 4028'-4039'N) in Inner Mongolia, which is described by them as being located "in the transitional zone between semi-arid and semi-humid conditions that is sensitive to East Asian monsoon variability."

What was learned
Jin et al. report that both types of data they obtained "support two distinct Little Ice Age cooling events centered at ~850 yr BP and ~150 yr BP," as well as "the Medieval Warm Period between 1200 and 900 yr BP," which they say "was warmer than the present, with higher chemical weathering than at present," additionally citing the study of Jin et al. (2002) to this effect.

What it means
Once again, we have a study that testifies to the occurrence of the Little Ice Age and Medieval Warm Period in a location far removed from the countries fringing the North Atlantic Ocean, which latter region is the only place on earth where climate alarmists are willing to admit the existence of these multi-century warm and cool periods that result from the millennial-scale oscillation of climate that is a pervasive feature of both glacial and interglacial epochs alike (see Climate Oscillations (Millennial Variability) in our Subject Index).  In addition, we have yet another part of the world where the Medieval Warm Period has been identified by researchers as having been warmer than it is there currently.

Reference
Jin, Z.D., Shen, J., Wang, S. and Zhang, E.  2002.  The Medieval Warm Period in the Daihai area.  Journal of Lake Sciences 14: 216-221.

Reviewed 13 April 2005