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MWP in Europe and Asia

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Dry Hot North German Summers Were More Common 1000 Years Ago, Scientists Report. Dry summers were not rare 1000 years ago. Researchers from the University of Greifswald’s research group ‘Landscape Ecology and Ecosystem Dynamics’ have been able to reconstruct 1000 years of the dry summer period in northern Germany. Beech forest – photo: Dr. Tobias Scharnweber The article ‘Removing the no-analogue bias in modern accelerated tree growth leads to stronger medieval drought’ was published in 2019’s February edition of the journal Scientific Reports. As part of the current collaborative research project BaltRap (The Baltic Sea and its Southern Lowlands: Proxy-Environment interactions in times of rapid changes), the researchers investigated growth rings in nearly 2000 living beech trees – including some from the university’s own Elisenhain forest – and archaeological wood used for construction from around 1000 A.D.

Industry fertilizing trees Trees now grow much faster than in the past. CO2 fertilizing trees Higher levels of CO2 in the air also encourage growth. Prof. Medieval Warm Period confirmed via cave study of 3000 years of climatic variations | Watts Up With That? Remote cave study reveals 3000 years of European climate variation Roaring Cave in Scotland. A study of its limestone has produced a unique 3000-year-long record of climatic variations that may have influenced historical events including the fall of the Roman Empire and the Viking Age of expansion. Credit: Courtesy of UNSW SYDNEY — University of New South Wales Australia-led research on limestone formations in a remote Scottish cave has produced a unique 3000-year-long record of climatic variations that may have influenced historical events including the fall of the Roman Empire and the Viking Age of expansion.

The study of five stalagmites in Roaring Cave north of Ullapool in north-west Scotland is the first to use a compilation of cave measurements to track changes in a climate phenomenon called the North Atlantic Oscillation. The study is published in the journal Scientific Reports. The paper: Abstract: Like this: Historical Grape Harvest Dates Show Modern Temperatures No Warmer Now Than Most Of The Last 1,000 Years. Public domain photo. Source here In a late February (2017) interview on a U.S. news program, mechanical engineer Bill Nye claimed that the settled science says humans have been warming the planet at a rate that is unnaturally and “catastrophically” fast since the year 1750 .

“It’s a settled question. The speed that climate change is happening is caused by humans. When pressed to identify the signature change affirming this rapid human-caused acceleration, Nye immediately cited viticulture evidence, or grape-growing practices in England and France. “Britain would not be very well suited to growing grapes as it is today [if not for human activity]. Apparently Bill Nye believes it is quite unusual to grow grapes in England. In other words, there is nothing unusual, unprecedented, or remarkable — let alone “catastrophically fast” — about either the pace or degree of warmth in the modern climate. Grape Harvesting 500 Kilometers North Of Present From 1100 – 1300 A.D. Easterbrook, 2011 Menzel, 2005.

Another paper refutes the Mann made hockey stick – MWP was ≈1°C warmer than current temperatures | Watts Up With That? This new paper uses a rather unique proxy; high-resolution samples micromilled from archaeological shells of the European limpet, Patella vulgata. Mr. Limpet would be proud. Now, even less credible than before (Photo credit: Wikipedia) A paper published this week in the journal Palaeogeography, Palaeoclimatology, Palaeoecology finds that the Medieval Warming Period “was warmer than the late 20th century by ~1°C.”

The paper adds to the peer-reviewed publications of over 1000 scientists in the Medieval Warm Period Project showing that the global Medieval Warming Period was warmer than the current warming period. Highlights: ► We investigated oxygen isotope ratios of Viking Age limpet shells. ► Seasonal SST was reconstructed for the early MCA (10th-12th centuries). ► Early MCA winters were cooler and summers were warmer than late 20th century. ► MCA seasonality was almost twice that of the late 20th century. The paper is titled: Here’s the Abstract: h/t to “The Hockey Schtick” Like this: Scotland 800-Year Reconstruction Shows Temperatures Were As Warm Or Warmer In The Past!

By P Gosselin on 7. October 2018 Scotland climate over past 800 years: Pre-industrial warm phases provide answers By Dr. Sebastian Lüning and Prof. Fritz Vahrenholt (German text translated/edited by P Gosselin) How do today’s temperatures fit into the climate-historical context? This is one of the main tasks of today’s climate research. Surprisingly, the scientists found that the current level of heat in Scotland had been reached and even exceeded several times in the past.

What follows is the abstract of the study published in November 2017 in the journal Climate Dynamics: Reconstructing 800 years of summer temperatures in Scotland from tree rings This study presents a summer temperature reconstruction using Scots pine tree-ring chronologies for Scotland allowing the placement of current regional temperature changes in a longer-term context. Figure 1: Reconstruction of summertime July-August temperatures in Scotland over the past 800 years, based on tree rings.

Tibetan Temperature Reconstruction Shows Medieval Warm Period Was Warmer Than Today! A team of scientists led by HE YuXin of the Department of Earth Sciences at the University of Hong Kong examined two lake cores extracted from the Tibetan Plateau in order to reconstruct the past temperature development. Source: East_Asia_topographic_map.png: Ksiom, the GNU Free Documentation License, Version 1.2 The two cores coming from two different lakes go back 2600 and 2200 years respectively.

Here’s the paper’s abstract (my emphasis): Considerable efforts have been made to extend temperature records beyond the instrumental period through proxy reconstructions, in order to further understand the mechanisms of past climate variability. Yet, the global coverage of existing temperature records is still limited, especially for some key regions like the Tibetan Plateau and for earlier times including the Medieval Warm Period (MWP).

Here we present decadally-resolved, alkenone-based, temperature records from two lakes on the northern Tibetan Plateau. The paper’s conclusion also adds: Hottest year ever? Giant clam reveals Middle Ages were warmer than today | Watts Up With That? While government science and media begin the ramp-up to claim 2014 as the “hottest year ever” China’s Sea’s biggest bivalve shows that the Middle Ages were warmer than today, when Carbon Dioxide was lower. From the Chinese Academy of Sciences: Two recent papers, one is in Earth-Science Reviews and the other is in Chinese Science Bulletin, have studied key chemical contents in micro-drilled giant clams shells and coral samples to demonstrate that in the South China Sea the warm period of the Middle Ages was warmer than the present.

The scientists examined surveys of the ratio of strontium to calcium content and heavy oxygen isotopes, both are sensitive recorders of sea surface temperatures past and present. The Roman and Mediaeval Warm Periods both showed up prominently in the western Pacific and East Asia. Sea surface temperatures varied considerably over the 2500-year period. Dr. Like this: Like Loading...