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The Medieval Warm Period in China's Tarim Basin
Reference
Ma, C-M., Wang, F-B., Cao, Q-Y., Xia, X-C., Li, S-F. and Li, X-S. 2008. Climate and environment reconstruction during the Medieval Warm Period in Lop Nur of Xinjiang, China. Chinese Science Bulletin 53: 3016-3027.

What was done
The authors analyzed multi-proxy data, including, in their words, "14C, grain size, microfossil, plant seeds, and geochemical elements" -- which they obtained from sediment retrieved from excavations made in the dry lake bed of Lop Nur China's West Lake (4027'129" N, 9020'083" E) -- in order "to amply discuss," as they describe it, "the climate and environment changes during the MWP," or Medieval Warm Period, which they identified as occurring between AD 900 and 1300.

What was learned
The six scientists report that the "sedimentary environment was stable around the MWP, with weak storm effect," while "the upper and lower sediments showed frequent strong storm effect." They also report that "microfossils and plant seeds were abundant in this stage [MWP], which indicated a warm and humid fresh or brackish lake environment." Thereafter, they say that "in the late period [AD 1300 to 1650], the environment turned worse, storm effect was intensified ... and the climate began to dry, leading to shriveling and death of many plants such as red willows."

What it means
Over the period AD 1100 to 1300, Ma et al. conclude that "the environment was the best," stating that "temperature was almost the same [as] or a little higher than [our italics] nowadays." Hence, we have another example of the widespread occurrence of the Medieval Warm Period and its equivalent or higher temperatures, relative to those of the Current Warm Period. For more on the significance of this and similar findings from around the world, see our Medieval Warm Period Project, which is dedicated to studying what is described by the Chinese researchers as "one of the most significant climate episodes in the world."

Reviewed 7 January 2009