And, if it happened today, a similar explosive eruption could do the same, releasing more than twice the amount of ozone-depleting halogen gases currently in stratosphere due to manmade emissions.
Bromine and chlorine are gases that “love to react — especially with ozone,” said Kirstin Krüger, a meteorologist with GEOMAR in Kiel, Germany. “If they reach the upper levels of the atmosphere, they have a high potential of depleting the ozone layer.”
New research by Krüger and her colleagues, which she presented today at a scientific conference in Selfoss, Iceland, combined a mixture of field work, geochemistry and existing atmospheric models to look at the previous Nicaraguan eruptions. And the scientists found that the eruptions were explosive enough to reach the stratosphere, and spewed out enough bromine and chlorine in those eruptions, to have an effect on the protective ozone layer. Krüger’s talk was at the American Geophysical Union’s Chapman Conference on Volcanism and the Atmosphere.
Steffen Kutterolf, a chemical volcanologist with GEOMAR and one of Krüger’s colleagues, tackled the question of how much gas was released during the eruptions. He analyzed gases that were trapped by minerals crystallizing in the magma chambers, and applied a novel method that involves using the high-energy radiation from the German Electron Synchrotron in Hamburg to detect trace elements, including bromine. From that, Kutterolf estimated the amount of gas within magma before the eruptions, as well as the gas content in the lava rocks post-eruption. The difference, combined with existing field data about the size of the eruption, allowed the scientists to calculate how much bromine and chlorine are released.
Previous studies have estimated that in large, explosive eruptions — the type that sends mushroom clouds of ash kilometers high — up to 25 percent of the halogens ejected can make it to the stratosphere. For this study, the research team used a more conservative estimate of 10 percent reaching the stratosphere, to calculate the potential ozone layer depletion.
Taking an average from 14 Nicaraguan eruptions, the scientists found bromine and chlorine concentrations in the stratosphere jumped to levels that are equivalent to 200 percent to 300 percent of the 2011 concentrations of those gases. The Upper Apoyo eruption 24,500 years ago, for example, released 120 megatons of chlorine and 600 kilotons of bromine into the stratosphere.
Volcanic sulfate aerosols alone can lead to an ozone increase — if chlorine levels are at low, pre-industrial levels, Krüger said. But bromine and chlorine are halogens, gases whose atoms have seven electrons in the outer ring. To reach a stable, eight-electron configuration, these atoms will rip electrons off of passing molecules, like ozone. So when an eruption also pumps bromine and chlorine levels into the stratosphere, the ozone-depleting properties of the gases together with aerosols is expected to thin the protective layer.
“As we have bromine and chlorine together, we believe that this can lead to substantial depletion,” she said. “And this is from one single eruption.”
Because the effects are in the stratosphere, where the volcanic gases can be carried across the globe, eruptions of tropical volcanoes could lead to ozone depletion over a large area, Krüger said, potentially even impacting the ozone over polar regions. However, that’s a question for future research to address. Some volcanic gases can last in the stratosphere up to six years, she added, although the most significant impacts from eruptions like Mount Pinatubo were within the first two years.
The next step in the research, Krüger said, is to investigate how much damage to the ozone layer the volcanic gases caused in the past — and what the damage could be from future volcanic eruptions in the active Central American region.
Kate Ramsayer | American Geophysical Union
Fast rising bedrock below West Antarctica reveals an extremely fluid Earth mantle
22.06.2018 | Technical University of Denmark
Polar ice may be softer than we thought
22.06.2018 | Eberhard Karls Universität Tübingen
In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.
Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
22.06.2018 | Materials Sciences
22.06.2018 | Earth Sciences
22.06.2018 | Life Sciences