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A 1300-Year Record of Climate Change in Northern India
Chauhan, M.S. 2006. Late Holocene vegetation and climate change in the alpine belt of Himachal Pradesh. Current Science 91: 1562-1567.

What was done
Working with a one-meter-deep sediment core retrieved from the Naychhudwari Bog (7743'E, 3230'N) of Himachal Pradesh, northern India, the author derived abundance distributions of the various types of pollen deposited in the sediments of this alpine-region bog over the past 1300 years.

What was learned
Chauhan's pollen analysis revealed the existence of two broad climatic episodes of warm-moist and cold-dry conditions, the first covering the period AD 650 to 1200 and the second from AD 1500 onwards. "In the global perspective," as the Indian scientist describes it, the first period "is equivalent to the Medieval Warm Period, which has been witnessed in most parts of the world [our italics]," while the second period "falls within the time-limit of [the] Little Ice Age."

Of the first of these two periods, Chauhan remarks that "the alpine belt of this region experienced warm and moist climate [and that] the glaciers receded and the tree-line ascended to higher elevations," which suggests the existence of a prior cooler and drier climate that we would equate with the Dark Ages Cold Period. Then, from AD 1500 "onwards," Chauhan writes that "the glaciers advanced and consequently the tree-line descended under the impact of [the] cold and dry climate in the region," which suggests that (1) the region has not yet become as warm as it was during medieval times, or (2) if such a level of warmth has been achieved, its temporal existence falls far short of that of the much longer Medieval Warm Period, or (3) both of the above.

What it means
In spite of climate-alarmist attempts to pretend that the Medieval Warm Period was a myth, real-world data from all around the globe continue to testify - almost weekly, as it were (see our Medieval Warm Period Project) - that the MWP was likely both longer and stronger than the Current Warm Period has been to date. This fact thus demonstrates that it is possible to have a globally-warmer earth than that of the present with much less CO2 in the air than there is currently, which in turn suggests that a return of whatever was responsible for the significant warmth of the Medieval Warm Period could be responsible for the warmth of today.

Reviewed 30 May 2007