Volcanic Eruptions: A Global Threat with Local Impact
The recent study from the University of St Andrews has shed light on the far-reaching consequences of volcanic eruptions, specifically the Newberry Pumice eruption in Oregon, USA. This eruption, which occurred in 686 AD, sent ash particles across the globe, reaching as far as Greenland, a distance of over 5000 km. This discovery challenges previous assumptions about the reach of volcanic ash and highlights the potential for even minor eruptions to cause significant global disruption.
What makes this finding particularly intriguing is the size of the eruption. Categorized as a VEI 4 event, it was relatively small compared to the Mount St Helens eruption in 1980 (VEI 5) but still managed to spread ash across the North Atlantic. This raises a critical question: how do we prepare for the risks posed by these relatively frequent eruptions when they can have such a global impact?
The study's lead author, Dr Helen Innes, emphasizes the challenge of tracing ash fragments to their source, especially those as tiny as 0.02 mm. The discovery of the Newberry Pumice eruption in a Greenland ice core, dated to within two years of 686 AD, was a significant breakthrough. This precision in dating allows researchers to better understand the eruption's timing and its potential hazards.
Dr William Hutchison, a co-author, points out the often-overlooked volcanic activity in North America, Russia, and Japan. These regions, he notes, can produce vast amounts of ash that spread across the Northern Hemisphere. The North Atlantic, a busy flight route, is particularly vulnerable to such eruptions, as evidenced by the large quantities of ash found in Greenland.
The Newberry volcano, located in the Cascade Volcanic Range, is still active and considered a high threat by the U.S Geological Survey. The study's senior author, Professor Andrea Burke, highlights the value of studying past eruptions to understand current risks. The elongated ash deposits near the volcano suggest strong winds during the eruption, which likely contributed to the ash's long-distance travel.
This research serves as a reminder that volcanic eruptions, regardless of size, can have far-reaching consequences. It underscores the importance of improving our understanding of these risks and developing coordinated disaster response management strategies. As Dr Hutchison suggests, the next globally disruptive eruption may be closer than we think, and we must be prepared to respond effectively.
