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Review paper finds Medieval Warming Period was global and warmer than the present

http://hockeyschtick.blogspot.com/2013/09/review-paper-finds-medieval-warming.html

A new review paper from SPPI and CO2 Science reviews the published literature on the Medieval Warming Period in South America and finds “(1) the Medieval Warm Period was a global phenomenon that was comprised of even warmer intervals than the warmest portion of the Current Warm Period, and that (2) the greater warmth of the Medieval Warm Period occurred when there was far less CO2 in the air than there is nowadays, which facts clearly demonstrate that the planet’s current – but not unprecedented – degree of warmth need not have been CO2-induced.”

For the Full Report in PDF Form, please click here.

[Illustrations, footnotes and references available in PDF version]

Excerpts:

Was there a Medieval Warm Period anywhere in addition to the area surrounding the North Atlantic Ocean, where its occurrence is uncontested? This question is of utmost importance to the ongoing global warming debate, since if there was, and if the locations where it occurred were as warm then as they are currently, there is no need to consider the temperature increase of the past century as anything other than the natural progression of the persistent millennial-scale oscillation of climate that regularly brings the earth several-hundred-year periods of modestly higher and lower temperatures that are totally independent of variations in atmospheric CO2 concentration. Hence, this question is here considered as it applies to South America, a region far removed from where the existence of the Medieval Warm Period was first recognized.

ST data indicate that the current level of warmth in that part of the world still has a long way to go before equaling the warmth experienced there a thousand and more years ago, which suggests that the region’s current level of warmth is neither unprecedented nor unnatural -and therefore need not be CO2-induced – as is also the case for most of the rest of the planet.

This finding of Neukom et al. goes a long ways towards demonstrating that: (1) the Medieval Warm Period was a global phenomenon that was comprised of even warmer intervals than the warmest portion of the Current Warm Period, and that (2) the greater warmth of the Medieval Warm Period occurred when there was far less CO2 in the air than there is nowadays, which facts clearly demonstrate that the planet’s current – but not …

Settled science update: Oceanographers find enormous deep-sea waves that ‘play a crucial role in long-term climate cycles’

http://hockeyschtick.blogspot.com/2013/09/settled-science-update-oceanographers.html

Settled science update: Oceanographers have recorded for the first time, in “a key bottleneck” of the Pacific Ocean, enormous 800-foot-tall deep-sea waves that “play a crucial role in long-term climate cycles.” “Climate models are really sensitive not only to how much turbulence there is in the deep ocean, but to where it is,” for which there is currently little to no data. According to the authors, “The primary importance of understanding deep-ocean turbulence is to get the climate models right on long timescales.” Indeed, natural ocean oscillations can alone explain half of the global warming of the 20th century, and the rest is explainable by global brightening and the sunspot time integral.

The deep-sea waves are 800 feet tall, as high as a skyscraper. (Credit: Tom Peacock, MIT | Wide Eye Productions)

Breaking Deep-Sea Waves, as High as a Skyscraper, Reveal Mechanism for Global Ocean Mixing

Sep. 9, 2013 — Waves breaking over sandy beaches are captured in countless tourist photos. But enormous waves breaking deep in the ocean are seldom seen, although they play a crucial role in long-term climate cycles.
A University of Washington study for the first time recorded such a wave breaking in a key bottleneck for circulation in the world’s largest ocean. The study was published online this month in the journal Geophysical Research Letters.The deep ocean is thought of as dark, cold and still. While this is mostly true, huge waves form between layers of water of different density. These skyscraper-tall waves transport heat, energy, carbon and nutrients around the globe. Where and how they break is important for the planet’s climate.”Climate models are really sensitive not only to how much turbulence there is in the deep ocean, but to where it is,” said lead author Matthew Alford, an oceanographer in the UW Applied Physics Laboratory. He led the expedition to the Samoan Passage, a narrow channel in the South Pacific Ocean that funnels water flowing from Antarctica.”The primary importance of understanding deep-ocean turbulence is to get the climate models right on long timescales,” Alford said.Dense water in Antarctica sinks to the deep Pacific, where it eventually surges through a 25-mile gap in the submarine landscape northeast of Samoa.”Basically the entire South Pacific flow is blocked by this huge submarine ridge,” Alford said. “The amount of …

New paper finds IPCC climate models don’t realistically simulate convection: Published in Geophysical Research Letters finds climate models do not realistically simulate convection, ‘a key element of the weather and climate system for transporting mass, momentum, and thermal energy’

New paper finds IPCC climate models don’t realistically simulate convection

http://hockeyschtick.blogspot.com/2013/09/new-paper-finds-ipcc-climate-models.html

More problems for the models: A paper published today in Geophysical Research Letters finds climate models do not realistically simulate convection, “a key element of the weather and climate system for transporting mass, momentum, and thermal energy,” because of a large gap in the scale or resolution required to simulate convection [1-2 km] compared to global atmospheric motions [on the order of 10,000 km].

According to the authors, “It has been challenging to simulate convection realistically in global atmospheric models, because of the large gap in spatial scales between convection (10^0 km) and global motions (10^4 km).” The authors find “an essential change for convection statistics occurred around 2-km grid spacing. The convection structure, number of convective cells, and distance to the nearest convective cell dramatically changed at this [2 km] resolution,” which is a much, much smaller resolution than used by IPCC climate models.

Skeptics such as Dr. Noor van Andel have previously pointed out that the so-called “human fingerprint” or “hot spot” of global warming [that exists only in climate models] is a consequence of incorrect assumptions regarding convection, and this new paper may shed light on the reasons why.
Deep moist atmospheric convection in a sub-kilometer global simulationYoshiaki Miyamoto, Yoshiyuki Kajikawa, Ryuji Yoshida, Tsuyoshi Yamaura, Hisashi Yashiro, Hirofumi Tomita
Deep moist atmospheric convection is a key element of the weather and climate system for transporting mass, momentum, and thermal energy. It has been challenging to simulate convection realistically in global atmospheric models, because of the large gap in spatial scales between convection (10^0 km) and global motions (10^4 km). We conducted the first ever sub-kilometer global simulation and described the features of convection. Through a series of grid-refinement resolution testing, we found that an essential change for convection statistics occurred around 2-km grid spacing. The convection structure, number of convective cells, and distance to the nearest convective cell dramatically changed at this resolution. The convection core was resolved using multiple grids in simulations with grid spacings less than 2.0 km.

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‘Lack of hurricanes helps climate change skeptics’ – Houston Chronicle

Excerpt: As Thomas Knutson of the National Oceanic and Atmospheric Administration noted recently, “the rising trend in Atlantic tropical storm counts is almost entirely due to increases in short-duration (less than 2-day) storms alone [which were] particularly likely to have been overlooked in the earlier parts of the record, as they would have had less opportunity for chance encounters with ship traffic.” As such, “the historical Atlantic hurricane record does not provide compelling evidence for a substantial greenhouse warming induced long-term increase.”…

AP warmist reporter Seth Borenstein: ‘Where have all the hurricanes (& tornadoes) gone? US gets much needed break from severe weather’

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Arctic Ice Report: Is The Same Thickness It Was 70 Years Ago: ‘In 1940, Arctic sea ice was two metres thick – which is about the same as now’

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Lowest Five Year Count Of US Hurricanes On Record: ‘Over the last five hurricane seasons, the US has had a total of three hurricane strikes – Irene, Issac and Sandy’

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Prof. Roger Pielke Jr.: Updated ‘Remarkable’ Major Hurricane Drought Figure — ‘2,878 days. The US major hurricane drought continues. This length of time is almost exactly twice as long as the previous ‘drought’ since 1915 (which was 1975-1979)’

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Reuters: Hurricane season a record-breaking dud? ‘May even enter the record books as marking the quietest start to any Atlantic hurricane season in decades’

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