Archives de catégorie : climate and geology

Volcanic eruptions drove ancient global warming event

by Marcus Gutjah et al., August 30,  2017 in PhysOrg


A natural global warming event that took place 56 million years ago was triggered almost entirely by volcanic eruptions that occurred as Greenland separated from Europe during the opening of the North Atlantic Ocean,

The amount of carbon released during this time was vast—more than 30 times larger than all the fossil fuels burned to date and equivalent to all the current conventional and unconventional fossil fuel reserves we could feasibly ever extract.” Ridgwell said.

An unexpected finding was that enhanced organic matter burial was important in ultimately sequestering the released carbon and accelerating the recovery of the Earth’s ecosystem without massive extinctions.

See also here

Réchauffement climatique : le CO2 atmosphérique n’a pas toujours été le coupable

by Alex Barral et al., 2017 (U. Lyon-CNRS)


La comparaison des fluctuations du CO2 atmosphérique retracées à partir de ces estimations avec des courbes des changements de température a révélé de fortes baisses du CO2 atmosphérique (200-300 ppm), couplées à de fortes hausses de la température moyenne à la surface du globe (5-8°C) à l’échelle de quelques millions d’années.

Discovery of Additional West Antarctic Volcanoes Furthers Natural over Man-Made Warming

by James E Kamis, August 23, in ClimateChangeDispatch


The now three-year-old Plate Climatology Theory is on the brink of total confirmation. This is the result of two just-released and very telling Antarctic research studies. Combining the results of these two studies with the massive amounts of pre-existing data it is possible to show with very high certainty that melting of West Antarctic glaciers is directly related to bedrock heat flow and chemically charged heated fluid flow from the 5,000-mile-long West Antarctic Rift System (see Figure 1).

Record-shattering 2.7-million-year-old ice core reveals start of the ice ages

by Paul Voosen, August 15, 2017


Scientists announced today that a core drilled in Antarctica has yielded 2.7-million-year-old ice, an astonishing find 1.7 million years older than the previous record-holder

(…)

If the new result holds up, says Yige Zhang, a paleoclimatologist at Texas A&M University in College Station, the proxies will need to be recalibrated. “We have some work to do.”

Geologists warn us about dangerous volcanoes. Will we spend pennies for warnings?

by Larry Kummer, August 15, 2017


While we obsess about climate change and debate if we live in the Anthropocene, we prepare poorly or not at all for natural forces like volcanoes that can level cities. This is folly we can no longer afford. Experts recommend a simple first step to better protect ourselves. Let’s start listening, or nature will teach us an expensive lesson.

California is the State most at risk due to its volcanoes near major cities, as shown in this map from the website of the California Volcano Observatory

35 New Papers Affirm Warmth, Elevated CO2 Are Good For The Earth And Its Inhabitants

by Kenneth Richard, August 14, 2017 in NoTricksZone


Future Global Warming Scenarios ‘Potentially Beneficial’, Cooling May Cause Ecological ‘Declines’ / Human Health Risks ‘Extremely Sensitive’ To Temperature, With Cold Temperatures More Dangerous/Mass Extinctions Caused By Cold Temperatures (Ice Ages), Not Global Warming/ …

Scientists discover 91 volcanoes below Antarctic ice sheet

by Robin McKie, August 12, 2017 The Guardian


The Edinburgh volcano survey, reported in the Geological Society’s special publications series, involved studying the underside of the west Antarctica ice sheet for hidden peaks of basalt rock similar to those produced by the region’s other volcanoes. Their tips actually lie above the ice and have been spotted by polar explorers over the past century.

See also here and here

Des scientifiques découvrent 91 nouveaux volcans sous les glaciers de l’Antarctique

Cooling Deep Oceans – and the Earth’s General Background Temperature

by Wim Röst, August 13, in WUWT (Andy May)


Five million years ago, average temperatures were higher than they are now. During the Pliocene, the era just before the period of the Quaternary Ice Ages, ‘glacials’ did not yet exist because temperatures were too high. As cooling of the deep seas continued, temperatures became that low that large surfaces of the Northern Hemisphere became covered with snow. The earth’s albedo grew fast and large ice sheets started to develop

Underground magma triggered Earth’s worst mass extinction with greenhouse gases

by Howard Lee, geologist, August 9, 2017 in WUWT


Earth’s most severe mass extinction, the “Great Dying,” began 251.94 million years ago at the end of the Permian period, with the loss of more than 90% of marine species. Precise rock dates published in 2014 and 2015 proved that the extinction coincided with the Siberian Traps LIP, an epic outpouring of lava and intrusions of underground magma covering an area of northern Asia the size of Europe.

But those rock dates presented science with a new puzzle: why was the mass extinction event much shorter than the eruptions? And why did the extinction happen some 300,000 years after the lava began to flow?

The Effects of the Bray Climate and Solar Cycle

by Andy May, August 8, 2017 in WUWT


The Bray cycle is about 2450 years from beginning to end and the Bray Lows, which are the coldest portion of the cycle, are the most important events.

The world is currently within the Quaternary Ice Age and nearly as cold as it has ever been. The normal average temperature of the world is around 20°C, some 5°C warmer than today. To keep recent warming in perspective, it is important to understand that even if the worse predictions of the IPCC were to occur, we would only be returning to the average temperature of the last 560 million years

Phanerozoic Global Temperature from Scotese 2015,

link in the post (.pdf)

Paleoclimate Cycles are Key Analogs for Present Day (Holocene) Warm Period

by Renee Hannon, August 4, 2017 in WUWT


Detailed pattern correlation of Earth’s temperature changes during the past 450 kyrs reveals observations about several cyclic climate patterns. The past four glacial cycles are increasing in duration from 89 kyrs to 119 kyrs. Within these glacial cycles, two warm periods occur about 200 kyrs apart and have strikingly similar temperature characteristics.

During the last 450 kyrs, the five major warm onsets with rapidly increasing temperatures are triggered by increases in the eccentricity, obliquity, and precession of Earth’s orbit. The nearly concurrent increase in these three astronomical forces appears a necessary component for a major warm onset. Obliquity is the dominate control for ending these major warm periods and entering a cooling phase. 

Does Belgian Holocene speleothem records solar forcing and cold events?

by M. Allan et al., July 11,  2017, in Climate of the Past


We present a decadal-centennial scale Holocene climate record based on trace elements contents from a 65 cm stalagmite (“Père Noël”) from Belgian Père Noël cave. Père Noël (PN) stalagmite covers the last 12.7 ka according to U/Th dating. High spatial resolution measurements of trace elements (Sr, Ba, Mg and Al) were done by Laser- Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). Trace elements profiles were interpreted as environmental and climate changes in the Han-sur-Lesse region.

See also here

The 2400-year Bray cycle

by Javier, July 11, 2017 in ClimatEtc.


In our attempt to better understand the nature of our planet’s abrupt climate changes I have already reviewed the glacial-interglacial cycle, and the Dansgaard-Oeschger cycle’s that take place during glacial periods. I now start reviewing the millennial climate cycles that abruptly impact the slowly changing Holocene climate. The most significant and regular one is the ~ 2400-year Bray cycle.

The Holocene context for Anthropogenic Global warming

by Ed Hoskins, June1, 2015


When considering the scale of temperature changes that alarmists anticipate because of Man-made Global Warming and their view of the disastrous effects of additional Man-made Carbon Dioxide emissions in this century, it is useful to look at climate change from a longer term, century by century and even on a millennial perspective.

(i) See also here

(ii) See also here

Three New Papers: Greenland 3-5°C Warmer With 40 Kilometers Less Ice Area 4,000-10,000 Years Ago

by Kenneth Richard, July 11, in ClimateChangeDispatch


It’s official. According to a new paper published in the journal Scientific Reports, Greenland has been cooling slightly since 2005.

This trend development may be a harbinger of what may be in store for the coming years.  Shifts in North Atlantic temperatures typically lead changes in the Arctic by a few years.  And throughout the North Atlantic, rapid cooling has been underway since 2005, plunging below the levels reached in the 1950s

Geologic forces fueling West Antarctica’s Larsen Ice Shelf Cracks

by James Kamis, July 4, 2017 in ClimateChangeDispatch


Geological heat flow is fueling bottom melting and associated cracks across West Antarctica’s Larsen Ice Shelf, having little to do with man-made global warming. Significant amounts of high-quality data and relevant geological observations support this revelation, given historical and current geological mapping efforts done in Antarctica.

                                       see here, image credit NASA

See also here (in French)

Life on Earth was nearly doomed by too little CO2

by  Dennis T. Avery, June 30, 2017 in WUWT


Carbon dioxide truly is “the gas of life.” The plants that feed us and wildlife can’t live without inhaling CO2, and then they exhale the oxygen that lets humans and animals keep breathing.

Our crop plants evolved about 400 million years ago, when CO2 in the atmosphere was about 5000 parts per million! Our evergreen trees and shrubs evolved about 360 million years ago, with CO2 levels at about 4,000 ppm. When our deciduous trees evolved about 160 million years ago, the CO2 level was about 2,200 ppm – still five times the current level.

See also here (in French)

COLLAPSE OF THE EUROPEAN ICE SHEET CAUSED CHAOS

by Maja Sojtaric, June 27, 2017


The Eurasian ice sheet was an enormous conveyor of ice that covered most of northern Europe some 23,000 years ago. Its extent was such that one could have skied 4,500 km continuously across it – from the far southwestern isles in Britain to Franz Josef Land in the Siberian Arctic. Suffice to say its existence had a massive and extremely hostile impact on Europe at the time.

This ice sheet alone lowered global sea-level by over 20 meters. As it melted and collapsed, it caused severe flooding across the continent, led to dramatic sea-level rise, and diverted mega-rivers that raged on the continent. A new model, investigating the retreat of this ice sheet and its many impacts has just been published in Quaternary Science Reviews.