Can climate change affect volcanic activity?

Vesuvius is part of a volcanic region that became more active when the Mediterranean Sea dried up about 5 million years ago. A study of the era suggests climate change can influence volcanic activity. @bberwyn photo.

Study suggests link between sea level and eruptions

Staff Report

European researchers say they’ve found more evidence supporting links between climate change and volcanic activity.

Geologists from Switzerland, France and Spain studied compared data on eruptions and climate from about 5 million years ago, finding that volcanic activity in southern Europe doubled during a time when the Mediterranean Sea dried up. They suspect that the changes on the surface contributed to the way magma behaves deep in the Earth.

The era they studied is known as the Messinian salinity crisis, when the Strait of Gibraltar was blocked and the Mediterranean temporarily isolated from the Atlantic, according to the study published in Nature Geoscience.

The geological record shows a sharp increase in volcanic activity, and the scientists concluded the spike can best be explained by the almost total drying out of the Mediterranean.

The trait of Gibraltar was shut on a temporary basis during the Messinian Era (from 5.96 to 5.33 million years ago) and that the Mediterranean Sea was isolated from the Atlantic. Thick layers of salt on the seabed, as well as river canyons carved through land that is now submerged, suggest the Mediterranean Sea’s level was much lower.

The study acknowledges that this hypothesis continues to be a source of debate, while exploring the potential links.

In a statement, University of Geneva geologist Pietro Sternai said it’s clear that changes at the surface of the Earth, like a sudden lowering of sea level, can change the pressure deep down around pockets of molten magma. Based on that, the researchers studied the changes in volcanic activity during the period. Tracing the age of crystals in volcanic deposits, they counted 13 eruptions around the Mediterranean between 5.9 and 5.3 million years ago ‚ÄĒ more than double the average over comparable time periods.

Why is the figure so high?

“The single logical explanation is the hypothesis that the sea dried out, since this is the only event powerful enough to alter the Earth’s pressure and magmatic production over the entire Mediterranean,” Sternai said.

The team used computer models to simulate the effect of the Mediterranean’s desiccation on pressure at depth and the impact on magma production. According to Sternai, the models show the only way to account for the increased vulcanism was that the level of the Mediterranean Sea dropped by about two kilometres.

Related research has suggested that melting ice sheets in the polar regions, as well as melting glaciers, could also contribute in various ways to increased volcanic activity.

 

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Sunday set: Back to the garden

Go local

As a step toward cutting our carbon footprint, we’ve started to become more conscious about what we eat, and cutting back on meat, especially beef, is one big step. But it also means thinking about where your food comes from. If you stop eating meat but you’re munching fruit that’s been transported 8,000 miles by an oil-powered freighter, it might not be so climate-friendly. These are part of our regular talks at the dinner table, and it all leads to more awareness and change. Austrian supermarkets and food producers help inform these conversations with labels showing the origins of various items, and organic almost goes without saying. As often as possible, we buy produce, and wild mushrooms, from a regional farmer who comes to town once a week. The best foods of all come from a backyard garden, like the luscious strawberries and grapes that grow at our friends’ house in Lower Austria. And wild food isn’t bad either, when you can get it. Blackberries off the vine? Yes, please!

Biologists see serious new threat to amphibians

Boreal toads are threatened by a fungal disease, but that’s not the only worry. @bberwyn photo.

Severe Perkinsea infections may be responsible for a significant number of frog die-offs

Staff Report

A emerging disease has been identified as another possible cause for amphibian die-offs, according to the U.S. Geological Survey. Scientists already know that chytridiomycosis and the ranavirus are linked to frog population declines worldwide.

New research suggests that that SPI (the abbreviation for severe Perkinsea infections) is the third most common infectious disease of frogs. Continue reading “Biologists see serious new threat to amphibians”

17 years later, feds still playing politics with threatened lynx

Routine studies delayed, protections lagging …

The U.S. Forest Service will track lynx this coming winter to learn how they are responding to changes in forest habitat and to human activities. PHOTO BY TANYA SHENK, COLORADO DIVISION OF WILDLIFE.

Staff Report

The U.S. Forest Service started dragging its feet on protecting lynx ever since the wild cat was designated as a threatened species in 2000, and that pattern continues to this day. The Center for Biological Diversity has released a document suggesting that the agency’s Northern Rockies office dawdled for eight months working on a routine biological assessment that is often done in just a few weeks.

Superficially at issue are regional forest plans for mining and logging in and near lynx habitat, but the CBD’s conservation expert said the delay is more disturbing because it’s linked with a GOP effort to weaken the Endangered Species Act. Continue reading “17 years later, feds still playing politics with threatened lynx”

EPA stops work on airline emissions standards

Air travel accounts for one of the fastest growing sources of greenhouse gas pollution. @bberwyn photo.

Agency’s move could violate federal environmental laws

Staff Report

A little more than a year after determining that greenhouse gas emissions from aircraft are a threat to public health, the EPA has stopped working on developing new standards for the air industry.

That’s not surprising, given that the Trump administration has sought to undermine nearly every rule set to limit heat-trapping pollution, but environmental advocates with the Center for Biological Diversity want to know more about the latest step backward by the EPA. Continue reading “EPA stops work on airline emissions standards”

Sunday set: Late summer

Bittersweet days …

From the marketplace out into the fields and forests, late summer brings a last flush of colorful blooms. Make sure to get out a few more times before the monochromatic days of fall and winter come along. Not that there’s anything wrong with a crystalline or wet world of white and gray, but it’s nice to tank up on some of summer’s energy when you can. These are some of my favorite end-of-season images from last year, taken at the Brunnenmarkt in Vienna, the Austrian Alps and the canyon country of southern France.

Western fires take toll on water supplies

Erosion a huge factor as burned areas grow

A wildfire burns in Texas. Photo via U.S. Forest Service.

Staff Report

The growth of wildfires in the West could double the amount of sediment moving through the region’s rivers, U.S. Geological researchers found in a new study. Increased sediments can affect both water quality and the amount of water available for communities.

The USGS scientists analyzed a collection of climate, fire and erosion models for 471 large watersheds throughout the western U.S. They found that by 2050, the amount of sediment in more than one-third of watersheds could at least double. In nearly nine-tenths of the watersheds, sedimentation is projected to increase by more than 10 percent.

Continue reading “Western fires take toll on water supplies”