Archives par mot-clé : Volcanism

Volcanoes fed by ‘mush’ reservoirs rather than molten magma chambers

by Imperial College London, December 4, 2018 in ScienceDaily


Volcanoes are not fed by molten magma formed in large chambers finds a new study, overturning classic ideas about volcanic eruptions.

Instead, the study suggests that volcanoes are fed by so-called ‘mush reservoirs’ — areas of mostly solid crystals with magma in the small spaces between the crystals.

Our understanding of volcanic processes, including those leading to the largest eruptions, has been based on magma being stored in liquid-filled ‘magma’ chambers — large, underground caves full of liquid magma. However, these have never been observed.

The new study, by researchers at Imperial College London and the University of Bristol and published today in Nature, suggests the fundamental assumption of a magma chamber needs a re-think.

Volcanoes and glaciers combine as powerful methane producers

by Lancaster University, November 20, 2018 in ScienceDaily


The Lancaster university-led research, which is featured in Scientific Reports, is the first published field study to show methane release from glaciers on this scale.

“This is a huge amount of methane lost from the glacial meltwater stream into the atmosphere,” said Dr Peter Wynn, a glacial biogeochemist from the Lancaster Environment Centre and corresponding author of the study. “It greatly exceeds average methane loss from non-glacial rivers to the atmosphere reported in the scientific literature. It rivals some of the world’s most methane-producing wetlands; and represents more than twenty times the known methane emissions of all Europe’s other volcanoes put together.”

Discovery Of Massive Volcanic CO2 Emissions Puts Damper On Global Warming Theory

by J.E. Kamis, November 6, 2018 in ClimateChangeDispatch


Recent research shows that the volume of volcanic CO2 currently being emitted into Earth’s atmosphere is far greater than previously calculated, challenging the validity of the man-made global warming theory.

he cornerstone principle of the global warming theory, anthropogenic global warming (AGW), is built on the premise that significant increases of modern era human-induced CO2 emissions have acted to unnaturally warm Earth’s atmosphere.

A warmed atmosphere that directly, or in some cases indirectly fuels anomalous environmental disasters such as ocean warming, alteration of ocean chemistry, polar ice sheet melting, global sea level rise, coral bleaching and most importantly dramatic changes in climate.

There are numerous major problems with the AGW principle.

Identification of Volcanic vs. Man-made CO2

USGS issues first USA Volcano Threat Assessment in over a decade

by Anthony Watts, October 24, 2018 in WUWT


18 volcanoes in the USA are classified as “very high threat”, many are in the Pacific Northwest.

Here the .pdf (USGS, 2018)

The United States has 161 young, active volcanoes within its borders. Since 1980, there have been 120 eruptions and 52 episodes of notable volcanic unrest at 44 U.S. volcanoes.

The U.S. Geological Survey systematically assesses U.S. volcanoes considered to be active or potentially active, and publishes a volcanic threat assessment that ranks the volcanoes based on 24 hazard and exposure factors. Last published in 2005, this 2018 update considers (1) field and laboratory research that adds or removes volcanoes from the list of potentially active volcanoes, and (2) updates the hazard and exposure factors used to produce a relative threat ranking of volcanoes.

Addressing on Abrupt Global Warming, Warming Trend Slowdown and Related Features in Recent Decades

by Indriani Roy, September28,  2018 in FrontiersinEarthScience


  • College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, United Kingdom

The puzzle of recent global warming trend slowdown has captured enough attention, though the underlying cause is still unexplained. This study addresses that area segregating the role of natural factors (the sun and volcano) to that from CO2 led linear anthropogenic contributions. It separates out a period 1976–1996 that covers two full solar cycles, where two explosive volcanos erupted during active phases of strong solar cycles. The similar period also matched the duration of abrupt global warming. It identifies that dominance of Central Pacific (CP) ENSO and associated water vapor feedback during that period play an important role. The possible mechanism could be initiated via a preferential alignment of NAO phase, generated by explosive volcanos. Inciting extratropical Rossby wave to influence the Aleutian Low, it has a modulating effect on CP ENSO. Disruption of Indian Summer Monsoon and ENSO during the abrupt warming period and a subsequent recovery thereafter can also be explained from that angle. Interestingly, CMIP5 model ensemble, and also individual models, fails to comply with such observation. It also explores possible areas where models miss important contributions due to natural drivers.

Iceland’s monster volcano charging up for eruption

by Anthony Watts, September 20, 2018 in WUWT


The Katla volcano, hidden beneath the ice cap of Mýrdalsjökull glacier in Iceland, has historically erupted violently once every 40-80 years.  In-as-much as it’s last such eruption took place one hundred years ago, in 1918, Katla’s next eruption is long overdue.

An eruption in Katla would dwarf the 2010 Eyjafjallajökull eruption, scientists have warned.

A new study by Icelandic and British geologists showed that Katla is emitting enormous quantities of CO2 – at least 20 kilotons of CO2 every day. Only two volcanoes worldwide are known to emit more CO2, Evgenia Ilyinskaya a volcanologist with the University of Leeds told the Icelandic National Broadcasting Service RÚV.

N ICE CAULDRON IN MÝRDALSJÖKULL Geothermal activity in the volcano’s caldera melts the glacier, creating cauldrons in the ice. Photo/Fréttablaðið

Napoleon at Waterloo versus the volcano – Napoleon lost

by Anthony Watts, August 23, 2018 in WUWT


Napoleon’s defeat at Waterloo caused in part by Indonesian volcanic eruption

Electrically charged volcanic ash short-circuited Earth’s atmosphere in 1815, causing global poor weather and Napoleon’s defeat, says new research.

Historians know that rainy and muddy conditions helped the Allied army defeat the French Emperor Napoleon Bonaparte at the Battle of Waterloo. The June 1815 event changed the course of European history.

Two months prior, a volcano named Mount Tambora erupted on the Indonesian island of Sumbawa, killing 100,000 people and plunging the Earth into a ‘year without a summer’ in 1816.

Now, Dr Matthew Genge from Imperial College London has discovered that electrified volcanic ash from eruptions can ‘short-circuit’ the electrical current of the ionosphere – the upper level of the atmosphere that is responsible for cloud formation.

The findings, published today in Geology, could confirm the suggested link between the eruption and Napoleon’s defeat.

A new volcanic province: an inventory of subglacial volcanoes in West Antarctica

by M. Van Wyk De Vries et al., August 16, 2018 in Geol.Soc.London


Abstract: The West Antarctic Ice Sheet overlies the West Antarctic Rift System about which, due to the comprehensive ice cover, we have only limited and sporadic knowledge of volcanic activity and its extent. Improving our understanding of subglacial volcanic activity across the province is important both for helping to constrain how volcanism and rifting may have influenced ice-sheet growth and decay over previous glacial cycles, and in light of concerns over whether enhanced geo- thermal heat fluxes and subglacial melting may contribute to instability of the West Antarctic Ice Sheet. Here, we use ice-sheet bed-elevation data to locate individual conical edifices protruding upwards into the ice across West Antarctica, and we propose that these edifices represent subglacial volcanoes. We used aeromagnetic, aerogravity, satellite imagery and databases of confirmed volca- noes to support this interpretation. The overall result presented here constitutes a first inventory of West Antarctica’s subglacial volcanism. We identified 138 volcanoes, 91 of which have not previously been identified, and which are widely distributed throughout the deep basins of West Antartica, but are especially concentrated and orientated along the >3000 km central axis of the West Antarctic Rift System.

Multiple NASA Studies Confirm Bedrock Heat Flow Behind Melting Polar Ice, Not Global Warming

by James E. Kamis, August 7, 2018 in ClimateChangeDisatch


In what amounts to dissension from National Aeronautics and Space Administration (NASA) climate change policy, a series of just-released studies by working-level scientists prove that geological and not atmospheric forces are responsible for melting of Earth’s polar ice sheets.

Volcanic Heat Found Under Antarctica’s Fastest-Melting Glacier

by M.  Bastach, June 28, 2018 in ClimateChangeDispatch


A group of scientists at the University of Rhode Island stumbled on something unexpected when analyzing data brought back from a 2014 expedition to western Antarctica.

Scientists found an abundance of the noble gas Helium-3, indicating there is a volcanic heat source beneath the Pine Island glacier — the fastest melting glacier in the South Pole. The findings were published in a study in the journal Nature Communications.

“When you find helium-3, it’s like a fingerprint for volcanism. We found that it is relatively abundant in the seawater at the Pine Island shelf,” chemical oceanographer Brice Loose, the study’s lead author, said in a statement.

See also here (National Science Foundation) and here

 

Stacking Up Volcanoes

by Willis Eschenbach, June 25, 2018 in WUWT


As readers of my posts know, I’ve held for many years that there are a variety of emergent phenomena that regulate the earth’s temperature. See my posts The Thermostat Hypothesisand Emergent Climate Phenomena for an overview of my hypothesis.

One of the predictions derivable from my hypothesis is that the earth should be relatively insensitive to small changes in forcing. According to my hypothesis, if the total energy entering the system changes in such a manner that the global temperatures start to drop, inter alia the system responds through changes in the time and strength of the daily emergence of the tropical cumulus field and the associated thunderstorms. This allows more sunlight to enter the system and decreases the thunderstorm-caused surface heat losses, balancing out the energy lost elsewhere and maintaining the temperature.

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Antarctic Ice Loss Tripled, from near zero to an extremely tiny number! (Nobody mention those volcanoes)

by JoNova, June 15, 2018


Quick — tax the magma

It’s another round of Antarctic Doom about next to nothing. In April Antarctica’s ice was melting five times faster than usual. Now it’s losing ice three times faster in the last five years than the 15 before that! What you won’t hear is how the Antarctic ice cap has 29 million cubic kilometers of ice and has been there for 30 million, mostly warmer, years. You also won’t hear how Antarctica was warmer in Roman Times, or that the  Antarctic Peninsula has cooled by almost 1 degree.

You also won’t hear a word about any volcanoes

The new paper has zero mentions of the word. But other scientists have published plenty of papers describing how the West Antarctic zone is being warmed from below by 1200 degrees of magma. According to scientist Dustin Schroeder and co,  it is as if the Thwaites Glacier in West Antarctic is sitting on a “stovetop burner”.[1]  His words. Thwaites Glacier,, smack in the middle of the warming is being melted from below by geothermal heat. Then there is the large blob of superheated rock 60 miles below West Antarctica. The researchers use the phrase “like a blow-torch”….  Capping it off, only last year 91 new volcanoes were discovered 2km underneath the West Antarctic Rift. That’s new, as in, we didn’t know they were there.

Follow the reasoning, either a trace gas 10 kilometers up is causing some spots of Antarctica to warm and other parts to cool, or hot magma at 1,200C is. What’s more likely?

When Eruptions Don’t

by Willis Essenbach, May 29, 2018 in WUWT


Inspired by Richard Keen’s interesting WUWT post on using eclipses to determine the clarity of the atmosphere, I went to the website of the Hawaiian Mauna Loa Observatory. They have some very fascinating datasets. One of them is a measurement of direct solar radiation, minute by minute, since about 1980.

I thought that I could use that dataset to determine the clarity of the atmosphere by looking at the maximum downwelling solar energy on a month by month basis. I’ve described my method of extracting the maximum solar energy from the minute by minute data in the appendix for those interested.

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60,000 gallons of Flammable Liquid Removed From Volcano Risk Hawaii Geothermal Plant

by Eric Worrall, May 12, 2018 in WUWT


Puna Geothermal Venture has removed 60,000 gallons of flammable Pentane from a geothermal plant in the path of the Hawaii volcanic eruption. But concerns remain that if the geothermal wells break, they could flood the neighbourhood with toxic volcanic gasses.

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Kilauea eastern rift zone fissure eruption May 2018. By United States Geological Survey [Public domain], via Wikimedia Commons

West Antarctic Volcano and Fault Belt Part of ‘Pacific Ring of Fire’

by J.E. Kamis, May 7, 2018 in ClimateChangeDispatch


The inclusion of the here-termed West Antarctic Volcano and Fault Belt into the Pacific Ring of Fire will raise scientific awareness concerning the idea, as per the Plate Climatology Theory, that geologically induced heat flow is the root cause of many anomalous changes in Antarctica’s ecosystems, oceans, climate, and ice masses.