How does rising atmospheric CO2 affect marine organisms?

Click to locate material archived on our website by topic

A Late-Holocene Palaeoclimate Record from the Higher Himalaya of India
Phadtare, N.R. and Pant, R.K. 2006. A century-scale pollen record of vegetation and climate history during the past 3500 years in the Pinder Valley, Kumaon Higher Himalaya, India. Journal of the Geological Society of India 68: 495-506.

What was done
Based on a study of the pollen and organic matter content and the magnetic susceptibility of radiocarbon-dated samples from a peat deposit in the Kumaon Higher Himalaya of India (303'N, 7056'E), the authors developed a 3500-year palaeoclimate record of the Late Holocene.

What was learned
"With an abrupt rise in temperature as well as moisture at ~AD 400," according to Phadtare and Pant, "the climate suddenly turned warm and moist and remained so until ~AD 1260," which time interval, in their words, is "generally referred to as the Medieval Warm Period in the Northern Hemisphere." Over the ensuing century, they report that the climate turned cold and dry, but then warm and wet again, before turning "cold and moist during ~AD 1540-1730," which latter climate episode is said by them to "represent the Little Ice Age event in the Garhwal-Kumaon Himalaya."

Subsequently, the Indian researchers say "the climate has been persistently wet with relatively higher temperatures until ca. AD 1940, followed by a cooling trend that continued till the present," which dramatic modern cooling is also observed in the regional tree-ring record of Yadav et al. (2004).

What it means
The results of this study provide yet another example of the now-quite-obvious fact that the Medieval Warm Period and Little Ice Age were global phenomena and not just regional anomalies confined to lands adjacent to the North Atlantic Ocean, as climate alarmists have long claimed.

Yadav, R.R., Park, W.K., Singh, J. and Dubey, B. 2004. Do the western Himalayas defy global warming? Geophysical Research Letters 31: 10.1029/2004GL020201.

Reviewed 2 May 2007