Here are the six hottest volcanoes to watch in 2018

The Bardarbunga volcano, Iceland, erupts in 2014. Image: Getty.

The eruption of Mount Agung on the island of Bali has sparked worldwide media interest, yet volcanic eruptions in Indonesia are nothing new. Of the country’s 139 “active” volcanoes, 18 currently have raised alert levels, signifying higher than normal seismic activity, ground deformation or gas emissions. On a global scale, in any week in 2017, there were at least between 14 and 27 volcanoes erupting.

Most observed volcanic activity takes place along the Pacific Ring of Fire, a region around the Pacific Ocean where several tectonic plates meet, causing earthquakes and a chain of what geologists call subduction zone volcanoes. Other eruptions occur at volcanoes within continental interiors such as Ol Doinyo Lengai in Tanzania, or on oceanic islands like Hawaii. Many also take place hidden from view on the sea floor, with some of the most active underwater volcanoes located in the Tonga-Kermadec island arc in the south-west Pacific.

Spot the ring of fire. Image: Global Volcanism Program/Smithsonian Institution.

The current eruptions on land range from gentle lava effusions to moderate-sized explosions and are tiny compared to the largest in Earth’s history. Even the 1815 eruption of Mount Tambora, also in Indonesia, arguably the largest eruption in recent recorded history, is dwarfed by super-eruptions in the geological past such as that of Toba volcano on Sumatra some 74,000 years ago. Toba erupted approximately 70 times more magma than Tambora, helped plunge the earth into another ice age and may have even created a genetic bottleneck in human evolution.

In fact, Toba was the largest eruption in the past 25m years, so there is little chance of a similar catastrophe any time soon. Nevertheless, it is the frequent, small- to moderate-sized eruptions that pose a constant volcanic threat. Around the globe today, about 800m people live within 100km, and 29m within 10km, of active volcanoes.

“Volcanic threat”, a measure that combines the level of hazard and the number of people exposed to it, is by far the highest in Indonesia, followed by the Philippines, Japan, Mexico and Ethiopia. These five countries combine to make up more than 90 per cent of the total global volcanic threat. However, as a proportion of population, volcanic threat is highest on small islands such as Montserrat, which are entirely volcanic.

Which are the volcanoes to watch in 2018? Some of the volcanoes that currently show signs of unrest may simply calm down without eruption, while others may enter a phase of eruption in the months to come and will need to be watched and monitored closely.

As well as Agung, here is our choice of some to keep an eye on:

Kirishima, Japan

One of Japan’s less known but most active volcanoes, Kirishima, is a group of several volcanic cones with eruptions recorded on and off since 742. An eruption at one of these cones, Shinmoedake, in 2011 was the largest at Kirishima for more than 50 years. Shinmoedake erupted for the first time in six years in October, with white plumes rising 200 metres above the crater rim. Presently, the alert level remains elevated.

Merapi, Indonesia

Merapi is one of the most dangerous volcanoes in Indonesia due to its frequent eruptions and densely populated slopes. With a death toll of nearly 400 people, its 2010 eruption is so far the deadliest of the 21st century. One may argue that another eruption of Merapi is overdue, although there are no immediate signs of increased volcanic activity or unrest.

Öræfajökull, Iceland

This ice-covered volcano has erupted twice since the early settlement of Iceland, including the country’s largest-ever explosive eruption in 1362 and another in 1727-28. In both cases the eruptions were followed by massive and lethal flooding, as meltwater from subglacial lakes on the mountain were suddenly released.

Öræfajökull appears to be waking up. Small seismic tremors inside the volcano have been recorded since August 2017 and, in November, a depression on the surface of the ice inside the main crater appeared – a phenomenon that is usually caused by ice melting below the surface as heat builds up.

Öræfajökull on November 10. The fuzzy area in the middle indicates melting ice. Image: Antti Lipponen/Sentinel–2B/creative commons.

Popocatépetl, Mexico

Mexico’s “smoking mountain”, pictured at the top of this article, lies 70km south-east of Mexico City and is the country’s most active volcano. The volcano is currently erupting – as it has done so intermittently since 2005 – with lava dome growth, explosions, ash plumes up to a few kilometres high and minor ash fall in surrounding areas.

Villarrica, Chile

Snow-covered Villarrica volcano is one of only a small number of volcanoes around the world with an active lava lake. A gradual increase in seismic and lava lake activity, producing lava fountains up to 150 metres high, have been documented since mid-November 2017.

Kilauea, US

Kilauea volcano on Hawaii’s Big Island has spewed basaltic lava almost continuously for 35 years and there is no reason to expect this eruption will end any time soon. The volcano continues to erupt at its summit and from the Puʻu ʻOʻo vent on its East Rift Zone, producing lava flows that occasionally enter the ocean.

Canned ravioli vs Puʻu ʻOʻo lava. Image: author provided.

The ConversationSo these are some of the volcanoes that will need to be monitored closely over the next weeks and months. But volcanic unrest can also start suddenly at dormant volcanoes such as Hekla in Iceland which, based on its past record of decades of quiescence followed by sudden huge eruptions, may awake with little warning.

Ralf Gertisser, Senior Lecturer in Mineralogy and Petrology, Keele University; Katie Preece, Research Associate in Volcanology, University of Glasgow, and Sylvain Charbonnier, Assistant Professor in Volcanology, University of South Florida.

This article was originally published on The Conversation. Read the original article.


 

 
 
 
 

Covid-19 is highlighting cities' unequal access to green space

In the UK, Londoners are most likely to rely on their local park for green space, and have the best access to parks. (Leon Neal/Getty Images)

As coronavirus lockdowns ease, people are flooding back to parks – but not everyone has easy access to green space in their city.

Statistics from Google show that park attendance in countries across the globe has shot up as people have been allowed to move around their cities again.

This is especially true in urban areas, where densely populated neighbourhoods limit the size of private green space – meaning residents have to go to the park to get in touch with nature. Readers from England can use our interactive tool below to find out how much green space people have access to in their area, and how it compares to the rest of the country.

 

Prime Minister Boris Johnson’s announcement Monday that people are allowed to mingle in parks and gardens with groups of up to six people was partially following what people were doing already.

Data from mobile phones show people have been returning to parks across the UK, and also across Europe, as weather improves and lockdown eases.

People have been returning to parks across the world

Stay-at-home requirements were eased in Italy on 4 May, which led to a flood of people returning to parks.

France eased restrictions on 1 May, and the UK eased up slightly on 13 May, allowing people to sit down in public places so long as they remain socially distanced.

Other countries have seen park attendance rise without major easing of lockdown – including Canada, Spain, and the US (although states there have individual rules and some have eased restrictions).

In some countries, people never really stopped going to parks.

Authorities in the Netherlands and Germany were not as strict as other countries about their citizens visiting local parks during lockdown, while Sweden has famously been avoiding placing many restrictions on people’s daily lives.


There is a growing body of evidence to suggest that access to green space has major benefits for public health.

A recent study by researchers at the University of Exeter found that spending time in the garden is linked to similar benefits for health and wellbeing as living in wealthy areas.

People with access to a private garden also had higher psychological wellbeing, and those with an outdoor space such as a yard were more likely to meet physical activity guidelines than those without access to outdoor space. 

Separate UK research has found that living with a regular view of a green space provides health benefits worth £300 per person per year.

Access is not shared equally, however, which has important implications for equality under lockdown, and the spread of disease.

Statistics from the UK show that one in eight households has no garden, making access to parks more important.

There is a geographic inequality here. Londoners, who have the least access to private gardens, are most likely to rely on their local park for green space, and have the best access to parks. 

However the high population in the capital means that on the whole, green space per person is lower – an issue for people living in densely populated cities everywhere.

There is also an occupational inequality.

Those on low pay – including in what are statistically classed as “semi-skilled” and “unskilled” manual occupations, casual workers and those who are unemployed – are almost three times as likely as those in managerial, administrative, professional occupations to be without a garden, meaning they rely more heavily on their local park.

Britain’s parks and fields are also at significant risk of development, according to new research by the Fields in Trust charity, which shows the number of people living further than a 10-minute walk from a public park rising by 5% over the next five years. That loss of green spaces is likely to impact disadvantaged communities the most, the researchers say.

This is borne out by looking at the parts of the country that have private gardens.

The least deprived areas have the largest gardens

Though the relationship is not crystal clear, it shows at the top end: Those living in the least deprived areas have the largest private green space.

Although the risk of catching coronavirus is lower outdoors, spending time in parks among other people is undoubtedly more risky when it comes to transmitting or catching the virus than spending time in your own outdoor space. 

Access to green space is therefore another example – along with the ability to work from home and death rates – of how the burden of the pandemic has not been equally shouldered by all.

Michael Goodier is a data reporter at New Statesman Media Group, and Josh Rayman is a graphics and data visualisation developer at New Statesman Media Group.