Climate change could increase volcano eruptions
Shrinking glacier cover could lead to increased volcanic activity in Iceland, warn scientists.
A new study, led by the University of Leeds, has found that there was less volcanic activity in Iceland when glacier cover was more extensive and as the glaciers melted volcanic eruptions increased due to subsequent changes in surface pressure.
Dr Graeme Swindles, from the School of Geography at Leeds, said: “Climate change caused by humans is creating rapid ice melt in volcanically active regions. In Iceland, this has put us on a path to more frequent volcanic eruptions.”
The study examined Icelandic volcanic ash preserved in peat deposits and lake sediments and identified a period of significantly reduced volcanic activity between 5,500 and 4,500 years ago. This period came after a major decrease in global temperature, which caused glacier growth in Iceland.
The human effect on global warming makes it difficult to predict how long the time lag will be but the trends of the past show us more eruptions in Iceland can be expected in the future.
The findings, published today in the journal Geology, found there was a time lag of roughly 600 years between the climate event and a noticeable decrease in the number of volcanic eruptions. The study suggests that perhaps a similar time lag can be expected following the more recent shift to warmer temperatures.
Iceland’s volcanic system is in process of recovering from the ‘Little Ice Age’ — a recorded period of colder climate roughly between the years 1500 to 1850. Since the end of the Little Ice Age, a combination of natural and human caused climate warming is causing Icelandic glaciers to melt again.
Dr Swindles said: “The human effect on global warming makes it difficult to predict how long the time lag will be but the trends of the past show us more eruptions in Iceland can be expected in the future.
“These long term consequences of human effect on the climate is why summits like COP are so important. It is vital to understand how actions today can impact future generations in ways that have not been fully realised, such as more ash clouds over Europe, more particles in the atmosphere and problems for aviation. “
Icelandic volcanism is controlled by complex interactions between rifts in continental plate boundaries, underground gas and magma build-up and pressure on the volcano’s surface from glaciers and ice. Changes in surface pressure can alter the stress on shallow chambers where magma builds up.
Even small changes in surface pressure can alter the likelihood of eruptions at ice-covered volcanos
Study co-author, Dr Ivan Savov, from the School of Earth & Environment at Leeds, explains: “When glaciers retreat there is less pressure on the Earth’s surface. This can increase the amount of mantle melt as well as affect magma flow and how much magma the crust can hold.
“Even small changes in surface pressure can alter the likelihood of eruptions at ice-covered volcanos.”
The research paper, Climatic control on Icelandic volcanic activity during the mid?Holocene, was published in Geology 16 November 2017.
For additional information and to request interviews please contact Anna Harrison, Press Officer at the University of Leeds, on +44 (0)113 34 34196 or a.harrison(at)leeds.ac.uk
University of Leeds
The University of Leeds is one of the largest higher education institutions in the UK, with more than 33,000 students from more than 150 different countries, and a member of the Russell Group of research-intensive universities.
We are a top ten university for research and impact power in the UK, according to the 2014 Research Excellence Framework, and are in the top 100 for academic reputation in the QS World University Rankings 2018. Additionally, the University was awarded a Gold rating by the Government’s Teaching Excellence Framework in 2017, recognising its ‘consistently outstanding’ teaching and learning provision. Twenty-four of our academics have been awarded National Teaching Fellowships – more than any other institution in England, Northern Ireland and Wales – reflecting the excellence of our teaching. www.leeds.ac.uk
Natural Environment Research Council
NERC is the UK's main agency for funding and managing research, training and knowledge exchange in the environmental sciences. Our work covers the full range of atmospheric, Earth, biological, terrestrial and aquatic science, from the deep oceans to the upper atmosphere and from the poles to the equator. We co-ordinate some of the world's most exciting research projects, tackling major issues such as climate change, environmental influences on human health, the genetic make-up of life on Earth, and much more. NERC is a non-departmental public body. We receive around £330m of annual funding from the Department for Business, Energy & Industrial Strategy (BEIS).