Woods Hole embraces the Medieval Warm Period – contradict Mann's proxy data

Hmmm, another installment in the supposedly "settled" science about climate change! From Greenie Watch: A new 2,000 year long reconstruction of sea surface temperatures (SST) from the Indo-Pacific warm pool (IPWP) suggests that temperatures in the region may have been as warm during the Medieval Warm Period as they are today. The IPWP is the largest body of warm water in the world, and, as a result, it is the largest source of heat and moisture to the global atmosphere, and an important component of the planet’s climate. Climate models suggest that global mean temperatures are particularly sensitive to sea surface temperatures in the IPWP. Understanding the past history of the region is of great importance for placing current warming trends in a global context. The study is published in the journal Nature. In a joint project with the Indonesian Ministry of Science and Technology (BPPT), the study’s authors, Delia Oppo, a paleo–oceanographer with the Woods Hole Oceanographic Institution, and her colleagues Yair Rosenthal of Rutgers State University and Braddock K. Linsley of the University at Albany-State University of New York, collected sediment cores along the continental margin of the Indonesian Seas and used chemical analyses to estimate water past temperatures and date the sediment. The cruise included 13 US and 14 Indonesian scientists. “This is the first record from the region that has really modern sediments and a record of the last two millennia, allowing us to place recent trends in a larger framework,” notes Oppo. Global temperature records are predominantly reconstructed from tree rings and ice cores. Very little ocean data are used to generate temperature reconstructions, and very little data from the tropics. “As palaeoclimatologists, we work to generate information from multiple sources to improve confidence in the global temperature reconstructions, and our study contributes to scientists’ efforts towards that goal,” adds Oppo. Temperature reconstructions suggest that the Northern Hemisphere may have been slightly cooler (by about 0.5 degrees Celsius) during the ‘Medieval Warm Period’ (~AD 800-1300) than during the late-20th century. However, these temperature reconstructions are based on, in large part, data compiled from high latitude or high altitude terrestrial proxy records, such as tree rings and ice cores, from the Northern Hemisphere (NH). Little pre-historical temperature data from tropical regions like the IPWP has been incorporated into these analyses, and the global extent of warm temperatures during this interval is unclear. As a result, conclusions regarding past global temperatures still have some uncertainties. More HERE (See the original for links, graphics etc.)

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