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Full Version: Big quake coming to Portland + New Zealand's disaster scenario + Snowball Earth fluke
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The Big Quake is Coming: Is Portland Prepared?
http://www.blueoregon.com/2017/03/big-qu...-prepared/

EXCERPT: Prominent geologists say we’re due for a powerful earthquake. Chances are 14-20% that it could hit in the next 50 years, experts say. The expected magnitude 9 quake hitting the Cascadia Subduction Zone would first hit at sea, creating a mighty tsunami with waves 50 to 100 feet high. Such a quake would roll inward through Portland to the Cascade Mountains, hitting an area from Eureka, California to Vancouver B.C. This quake would create violent shaking for three to four minutes, collapsing buildings and creating massive havoc. The Portland City Club created a study committee, which, late last month made 14 recommendations in its 84-page report (pdf).

The City Club report, however, just doesn’t go far enough in three crucial areas -- how to prevent loss of life during and immediately after the big quake; why we need an early warning system; and how to pay now for life-saving solutions. The local press did not publicize the report widely, and it is likely that the report's recommendations, like those of so many City Club studies, will go unheeded.

According to a less-than-comprehensive Portland Bureau of Development Services survey of the city, more than 1,700 buildings, built between 1870 and 1960, are built with unreinforced masonry. These buildings will collapse partially or completely, killing people in and near them....



Magnitude-8.2: The disaster scenario on New Zealand's most dangerous fault
http://www.stuff.co.nz/the-press/news/90...rous-fault

EXCERPT: [...] When the first Polynesian explorers circumnavigated the South Island, coming across the spectacular, snow-capped Southern Alps, they didn't know what it represented; one tectonic plate grinding against another for millennia, pushing the great mountains upwards. Neither did the first European settlers, who built communities on the West Coast, unaware of the tectonic churning deep into the earth, a great dragon beneath. It wasn't until the mid-20th century when the Alpine Fault was discovered at all. By then, it was too late. Two geologists were traversing remote Westland in search of mica, a material used in electrical components; they took the opportunity to do geological mapping of the region, which had not been done before. With the trained eyes of surveyors, they saw the way the mountain faces dropped in a steep, uniform line, the way rock had eroded to form a valley like depression, and knew what that represented.

Lives had already been built on the fault; the main road, at points, ran parallel. The town of Franz Josef is on top of it. All of the West Coast's population centres were built dangerously close to the fault, before anyone knew it was there. In the decades since, understanding of the fault has grown immensely. Last week, research based on a more complete earthquake record revised the return period of a quake to 291 years. The last was in 1717, exactly 300 years ago. Every year that passes pushes us further into the wrong end of that equation. A succession of earthquakes has the country on high alert. They are now turning to the Alpine Fault, the one everyone knows presents the biggest threat. Over the last few months, emergency management officials throughout the South Island have been preparing for what to expect, and how to coordinate a response.

Much of the South Island is expected to lose power immediately. Some communities, particularly on the West Coast and in western Otago, won't have power for weeks. Depending on the damage to the island's hydroelectric schemes, the electricity problem could extend further. They supply around 50 per cent of the country's power, putting the whole country under strain. [...] An Alpine Fault rupture would likely be 400km long, stretching across much of the island. Everyone in the South Island would be within the area of impact.

[...] Large, remote communities, such as the Gloriavale Christian community near Haupiri, which is just several hundred metres from the fault, will likely be devastated and completely cut-off. The extent of the damage further afield will be unknown for weeks. Helicopters will be dispatched to isolated areas, but there will be so many it could take weeks to get to everyone. Communications across the West Coast and the Queenstown-Lakes district could be down for weeks. For a long time, people will be left to themselves in isolated areas, completely and utterly alone. Many of the large problems caused by the earthquake will stem from one singularly massive problem: landslides....



A perfect storm of fire and ice may have led to snowball Earth: Explaining a 'once-in-a-billion-year event'
https://www.sciencedaily.com/releases/20...160813.htm

RELEASE: What caused the largest glaciation event in Earth's history, known as 'snowball Earth'? Geologists and climate scientists have been searching for the answer for years but the root cause of the phenomenon remains elusive. Now, Harvard University researchers have a new hypothesis about what caused the runaway glaciation that covered Earth pole-to-pole in ice. The research is published in Geophysical Research Letters.

Researchers have pinpointed the start of what's known as the Sturtian snowball Earth event to about 717 million years ago -- give or take a few 100,000 years. At around that time, a huge volcanic event devastated an area from present-day Alaska to Greenland. Coincidence? Harvard professors Francis Macdonald and Robin Wordsworth thought not. "We know that volcanic activity can have a major effect on the environment, so the big question was, how are these two events related," said Macdonald, the John L. Loeb Associate Professor of the Natural Sciences.

At first, Macdonald's team thought basaltic rock -- which breaks down into magnesium and calcium -- interacted with CO2 in the atmosphere and caused cooling. However, if that were the case, cooling would have happened over millions of years and radio-isotopic dating from volcanic rocks in Arctic Canada suggest a far more precise coincidence with cooling. Macdonald turned to Wordsworth, who models climates of non-Earth planets, and asked: could aerosols emitted from these volcanos have rapidly cooled Earth? The answer: yes, under the right conditions. "It is not unique to have large volcanic provinces erupting," said Wordsworth, assistant professor of Environmental Science and Engineering at the Harvard John A. Paulson School of Engineering and Applied Science. "These types of eruptions have happened over and over again throughout geological time but they're not always associated with cooling events. So, the question is, what made this event different?"

Geological and chemical studies of this region, known as the Franklin large igneous province, showed that volcanic rocks erupted through sulfur-rich sediments, which would have been pushed into the atmosphere during eruption as sulfur dioxide. When sulfur dioxide gets into the upper layers of the atmosphere, it's very good at blocking solar radiation. The 1991 eruption of Mount Pinatubo in the Philippines, which shot about 10 million metric tons of sulfur into the air, reduced global temperatures about 1 degree Fahrenheit for a year. Sulfur dioxide is most effective at blocking solar radiation if it gets past the tropopause, the boundary separating the troposphere and stratosphere. If it reaches this height, it's less likely to be brought back down to earth in precipitation or mixed with other particles, extending its presence in the atmosphere from about a week to about a year. The height of the tropopause barrier all depends on the background climate of the planet -- the cooler the planet, the lower the tropopause.

"In periods of Earth's history when it was very warm, volcanic cooling would not have been very important because Earth would have been shielded by this warm, high tropopause," said Wordsworth. "In cooler conditions, Earth becomes uniquely vulnerable to having these kinds of volcanic perturbations to climate."

"What our models have shown is that context and background really matters," said Macdonald.

Another important aspect is where the sulfur dioxide plumes reach the stratosphere. Due to continental drift, 717 million years ago, the Franklin large igneous province where these eruptions took place was situated near the equator, the entry point for most of the solar radiation that keeps Earth warm. So, an effective light-reflecting gas entered the atmosphere at just the right location and height to cause cooling. But another element was needed to form the perfect storm scenario. After all, the Pinatubo eruption had similar qualities but its cooling effect only lasted about a year.

The eruptions throwing sulfur into the air 717 million years ago weren't one-off explosions of single volcanoes like Pinatubo. The volcanoes in question spanned almost 2,000 miles across Canada and Greenland. Instead of singularly explosive eruptions, these volcanoes can erupt more continuously like those in Hawaii and Iceland today. The researchers demonstrated that a decade or so of continual eruptions from this type of volcanoes could have poured enough aerosols into the atmosphere to rapidly destabilize the climate. "Cooling from aerosols doesn't have to freeze the whole planet; it just has to drive the ice to a critical latitude. Then the ice does the rest," said Macdonald.

The more ice, the more sunlight is reflected and the cooler the planet becomes. Once the ice reaches latitudes around present-day California, the positive feedback loop takes over and the runaway snowball effect is pretty much unstoppable. "It's easy to think of climate as this immense system that is very difficult to change and in many ways that's true. But there have been very dramatic changes in the past and there's every possibility that as sudden of a change could happen in the future as well," said Wordsworth.

Understanding how these dramatic changes occur could help researchers better understand how extinctions occurred, how proposed geoengineering approaches may impact climate and how climates change on other planets. "This research shows that we need to get away from a simple paradigm of exoplanets, just thinking about stable equilibrium conditions and habitable zones," said Wordsworth. "We know that Earth is a dynamic and active place that has had sharp transitions. There is every reason to believe that rapid climate transitions of this type are the norm on planets, rather than the exception."
hhmmmm

sorry forgot to ask...
i know the US government doesnt beleive in climate change..
i wonder if the US government beleives in earth quakes.

probably not