The top 10 volcanic explosions in history: Sulfate deposits reveal the most destructive eruptions of the last 2,000 years


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Following powerful volcanic eruptions, large amounts of sulfur dioxide deposit themselves in ice cores buried deep within the Antarctic.

By studying these deposits, researchers from Nevada have been able to accurately plot the most explosive of these events during the past 2,000 years.

Topping the list was the eruption at Samalas, Indonesia in 1257, followed by the Kuwae event of 1452, and Tambora in 1815.

Although the study plots earlier events, the researchers don't know exactly what these explosions were.

Researchers studied records of global ice core sulfate data collected from Antarctica. In total, the study looked at 26 ice core records collected in an array of 19 sites from across Antarctica. Samalas was the most explosive eruption, and it took place in 1257 in Indonesia's Mount Rinjani's (pictured)

Researchers studied records of global ice core sulfate data collected from Antarctica. In total, the study looked at 26 ice core records collected in an array of 19 sites from across Antarctica. Samalas was the most explosive eruption, and it took place in 1257 in Indonesia's Mount Rinjani's (pictured)

The scientists, led by Michael Sigl and Joe McConnell of Nevada's Desert Research Institute (DRI), studied 26 ice core records from 19 sites across Antarctica.

It is the most accurate and precise reconstruction to date of historic volcanic sulfate emissions in the Southern Hemisphere, and is the first annually resolved record extending through the Common Era - the last 2,000 years of human history.

 

Powerful volcanic eruptions are one of the most significant causes of climate variability in the past due to the large amounts of sulfur dioxide they emit.

This leads to the formation of microscopic particles known as volcanic sulfate aerosols.

These aerosols reflect more of the sun's radiation back to space and ultimately cool the Earth's temperature.

THE TOP 10 MOST POWERFUL EXPLOSIONS OF ALL TIME

During the research, the scientists discovered evidence of 116 events - and the top ten are pictured in red. Topping the list was Samalas, Indonesia in 1257, followed by Kuwae in 1458, and Tambora in 1815. The researchers are unsure exactly what the earlier explosions were but have been able to plot the years for the fourth, fifth and sixth

During the research, the scientists discovered evidence of 116 events - and the top ten are pictured in red. Topping the list was Samalas, Indonesia in 1257, followed by Kuwae in 1458, and Tambora in 1815. The researchers are unsure exactly what the earlier explosions were but have been able to plot the years for the fourth, fifth and sixth

Topping the list was the eruption at Samalas, Indonesia in 1257, followed by the Kuwae event of 1452, and Tambora, also in Indonesia,  in 1815. 

Although the study plots earlier events, the researchers don't know exactly what these explosions were.

Based on the timeline, however, it's possible to estimate what these events may have been.

For example, the fourth most powerful eruption took place in around 674 AD, which could have been the Pago event in Bismarck or the eastern Alaskan eruption in Mount Churchill of 700.

Fifth and sixth place occurred between 531 to 566 AD and could be the Rabaul Caldera explosions in Papua New Guinea that took place in 535 and 536.

The seventh most powerful explosion happened shortly after Samalas, and may have been Quilatoa in the Andes in 1280.

Based on the 450 AD date of the eighth place event suggests it was Ilopango in Central America, ninth appears to have been the Grímsvötn and Laki eruptions in Iceland around 1785.

While tenth place happened shortly before Samalas and could have been an earlier eruption of Mount Rinjani, Indonesia.

Past volcanic events are measured using sulfate deposition records found in ice cores, and have been linked to short-term global and regional cooling.

The latest research brought together an array of ice core sulfate data in the world, including the West Antarctic Ice Sheet (WAIS) Divide ice core - said to be the most detailed record of volcanic sulfate in the Southern Hemisphere.

By studying the levels of sulphate deposits, the team were able to construct a timeline that shows when the largest eruptions took place, based on the level of sulphate found, and which were the most destructive.

A Desert Research Institute scientist examines a freshly drilled ice core in the field before ice cores are analysed in DRI's ultra-trace ice core analytical laboratory (left). Locations of Antarctic ice core sites used for volcanic sulfate aerosol deposition reconstruction are pictured right

A Desert Research Institute scientist examines a freshly drilled ice core in the field before ice cores are analysed in DRI's ultra-trace ice core analytical laboratory (left). Locations of Antarctic ice core sites used for volcanic sulfate aerosol deposition reconstruction are pictured right

Topping the list was the eruption at Samalas, Indonesia in 1257, followed by the Kuwae event of 1452, and Tambora in 1815. 

Most notably, the research found that the two largest volcanic eruptions in recent Earth history deposited 30 to 35 percent less sulfate in Antarctica, suggesting that these events had a weaker cooling effect on global climate than previously thought.

STUDYING ICE CORE RECORDS

Powerful volcanic eruptions are one of the most significant causes of climate variability in the past due to the large amounts of sulfur dioxide they emit.

This leads to the formation of microscopic particles known as volcanic sulfate aerosols.

These aerosols reflect more of the sun's radiation back to space and ultimately cool the Earth's temperature.

Past volcanic events are measured using sulfate deposition records found in ice cores, and have been linked to short-term global and regional cooling.

These reconstructions are critical to accurate model simulations used to assess past natural and anthropogenic climate changes.

Such model simulations underpin environmental policy decisions including those aimed at regulating greenhouse gas and aerosol emissions to curb projected global warming.

Although the study plots earlier events, it is unclear what these explosions were.

Based on the timeline, however, it's possible to hypothesise what these events may have been.

For example, the fourth most powerful eruption took place in around 674 AD, which could be the Pago event in Bismarck in 710, or the eastern Alaskan eruption in Mount Churchill of 700.

Fifth and sixth place occurred between 500 to 600 AD and could be the Rabaul Caldera explosions that took place in 535 and 536.

The seventh most powerful explosion happened shortly after Samalas, and may have been Quilatoa in the Andes in 1280.

Based on the 450 AD date of the eighth place event suggests it was Ilopango in Central America, and tenth place happened shortly before Samalas and could have been an earlier eruption of Mount Rinjani.

'This record provides the basis for a dramatic improvement in existing reconstructions of volcanic emissions during recent centuries and millennia,' said the report's lead author Michael Sigl, a postdoctoral fellow and specialist in DRI's unique ultra-trace ice core analytical laboratory, located on the Institute's campus in Reno, Nevada.

These reconstructions are critical to accurate model simulations used to assess past natural and anthropogenic climate changes.

Such model simulations underpin environmental policy decisions including those aimed at regulating greenhouse gas and aerosol emissions to curb projected global warming.

'This work is the culmination of more than a decade of collaborative ice core collection and analysis in our lab here at DRI,' said Joe McConnell, a DRI research professor who developed the continuous-flow analysis system used to analyze the ice cores.

An ice core section (picutred) is simultaneously analysed for a variety of elements and chemical species in DRI's ultra-trace ice core laboratory while slowly melting the ice on a heated melter plate

An ice core section (picutred) is simultaneously analysed for a variety of elements and chemical species in DRI's ultra-trace ice core laboratory while slowly melting the ice on a heated melter plate

McConnell, a member of several research teams that collected the cores, including the 2007 to 2009 Norwegian-American Scientific Traverse of East Antarctica and the WAIS Divide project that reached a depth of 3,405 meters in 2011, added, 'The new record identifies 116 individual volcanic events during the last 2000 years.'

'Our new record completes the period from years 1 to 500 AD, for which there were no reconstructions previously, and significantly improves the record for years 500 to 1500 AD,' Sigl added.

This new record also builds on DRI's previous work as part of the international Past Global Changes (PAGES) effort to help reconstruct an accurate 2,000-year-long global temperature for individual continents.

Simulations of volcanic sulfate transport performed with a coupled aerosol-climate model were compared to the ice core observations and used to investigate spatial patterns of sulfate deposition to Antarctica. The third most explosive event took place at Tombora in Indonesia (pictured) in 1815

Simulations of volcanic sulfate transport performed with a coupled aerosol-climate model were compared to the ice core observations and used to investigate spatial patterns of sulfate deposition to Antarctica. The third most explosive event took place at Tombora in Indonesia (pictured) in 1815

Simulations of volcanic sulfate transport performed with a coupled aerosol-climate model were compared to the ice core observations and used to investigate spatial patterns of sulfate deposition to Antarctica.

'Both observations and model results show that not all eruptions lead to the same spatial pattern of sulfate deposition,' said Matthew Toohey from the German institute GEOMAR Helmholtz Centre for Ocean Research Kiel. He added,

'Spatial variability in sulfate deposition means that the accuracy of volcanic sulfate reconstructions depends strongly on having a sufficient number of ice core records from as many different regions of Antarctica as possible.'

The findings are published in Nature Climate Change journal.


 



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