By Jim Le Maistre

300 kilometers off the coast of Oregon there is an undersea volcano, The Axial Seamount. It erupted in 1982, 1998, 2011 and 2015. New Scientist July 9 th , 2007 suggests that there are roughly 3 million volcanoes under the oceans of the world, this one is the only under sea volcano ever, regularly, studied. It is estimated that about 80 % of all volcanic activity on Earth occurs under the oceans. Almost nothing is known about these volcanoes. Scientists do not even have a scale by which to measure volcanoes that erupt under the sea. No system has ever been developed to describe or rate their magnitude like the systems rating Volcanoes above land.

Environment Canada – August 2015 . . . arrow pointing to ’Axial Seamount’- by author

Read the whole article: https://carbon-sense.com/wp-content/uploads/2022/07/axial-sea-mount.pdf [PDF, 881 KB]

By Alvin Wong and Wyss Yim. Volcanoes Study Group, Hong Kong.

Summary

During late 2021, the Hunga Tonga-Hunga Ha’apai submarine volcano erupted creating a new island which erupted sub-aerially on 15^th January, 2022 sending a plume 58 km above sea level penetrating the mesosphere. The study of observation records including satellite data has revealed warming of the ocean-surface layer followed by atmospheric cooling caused by the release of geothermal heat and volcanic materials entering the atmosphere respectively. Environmental factors influencing weather include the development of a relatively ‘short’ life-span South Pacific Blob; the transfer of large quantities of water vapour from the ocean into the atmosphere; the low-pressure condition on the ocean surface; the formation of clouds; the reduction of solar radiation caused by volcanic materials in the atmosphere; the strengthening of trade winds; the meandering of jet streams; the development of atmospheric rivers, the additional cooling effect of torrential rainfall, and, the switch to La Niña conditions. The record rainfall in eastern Australia and New Zealand and Tropical Cyclone Dovi occurring in February 2022 were both outcomes of atmospheric cooling following the sub-aerial eruption. (more…)