Tsunami made worse by 'pop-up' of sediments

Tsunami created by undersea earthquakes can be made much larger by the “pop-up” movement of large amounts of sediment, research suggests.

These quakes release huge amounts of energy as tectonic plates which stick as they pass each other suddenly slip.

But a study in Earth and Planetary Science Letters suggests that wedges of sediment scraped from the plates can pop up, boosting the resulting tsunami.

It suggests that spotting these wedges could improve large tsunami prediction.

Megathrust earthquakes are the sudden release of “elastic” energy stored as tectonic plates grind against each other, deforming but not slipping.

Typically, as in the Japan earthquake of March 2011 that caused a massive tsunami and the Fukushima nuclear disaster, this occurs at a subduction zone, where one plate is sliding beneath the next.

The quake arises when the deformation becomes too great and the stored energy suddenly releases.

The sudden plate movement is transmitted into the ocean, inducing a tsunami.

Prismatic view

Now, two eminent seismology researchers from Cambridge University, Dan McKenzie and James Jackson, have come up with a different idea.

Prof McKenzie, a founder of the idea of plate tectonics, explained that the idea arose from studies of the sea floor surrounding the site of the 2011 Tohoku earthquake off Japan.

“A Japanese submersible went down after the Tohoku earthquake and found not at all what everybody expected - which is that actually the tsunami was generated by the Japanese plate overriding the Pacific plate and moving upwards,” he told BBC News.

“But what this submersible found was… there was a fault which had moved the other way: instead of Japan moving upwards over the Pacific (plate), actually Japan had moved downward.” More

 

Building Resilience In A Changing Climate - Richard Heinberg

Climate shocks are on the way. We’ve already spewed so much carbon into the atmosphere that a cascade of worsening crop failures, droughts, floods, and freak storms is virtually guaranteed. You, your family, and your community will feel the effects.

Ironically, however, avoiding climate change also has its costs. It makes sense from a climate-protection standpoint to dramatically and rapidly reduce our use of fossil fuels, which drive global warming. But these fuels largely, well, fueled the spectacular economic growth of the past 200 years, and weaning ourselves from them quickly now—while most industrial economies are over-indebted and starved for growth—could risk financial upheaval.

Oil, the most economically pivotal of the fossil fuels, is getting more expensive anyway. Cheap, onshore, conventional crude is depleting; its replacements—deepwater oil, tar sands, and tight oil—cost more to produce, in both dollar and environmental terms. Though high oil prices discourage driving (good for the climate), they also precipitate recessions (bad for the economy). While renewable energy sources are our hope for the future and we should be doing everything we can to develop them, it will be decades before they can supply all our energy needs.

In the face of impending environmental and economic shocks, our best strategy is to build resilience throughout society. Resilience is the subject of decades of research by ecologists and social scientists who define it as “the capacity of a system to tolerate disturbance without collapsing into a qualitatively different state that is controlled by a different set of processes.” In other words, resilience is the capacity to absorb shocks, reorganize, and continue functioning.

In many respects a resilient society defies the imperative of economic efficiency. Resilience needs dispersed inventories and redundancy, while economic efficiency—in its ruthless pursuit of competitive advantage—eliminates inventories and redundancies everywhere it can. Economic efficiency leads toward globalization, resilience toward localization. Economic efficiency pursues short-term profit as its highest objective, while resilience targets long-term sustainability. It would appear that industrial society circa 2012 has gone about as far in the direction of economic efficiency as it is possible to go, and that a correction is necessary and inevitable. Climate change simply underscores the need for that course correction.

Building resilience means helping society to work more like an ecosystem—and that has major implications for how we use energy. Ecosystems conserve energy by closing nutrient loops: plants capture and chemically store solar energy, which is then circulated as food throughout the food web. Nothing is wasted. We humans—having developed the ability to draw upon ancient, concentrated, cheap, and abundant (though ultimately finite) fossil fuels—have simultaneously adopted the habit of wasting energy on a colossal scale. Our food, transport, manufacturing, and dwelling systems burn through thirty billion barrels of oil and eight billion tons of coal per year; globally, humans use over four hundred quadrillion BTUs of energy in total. Even where energy is not technically going to waste, demand for it could be substantially reduced by redesigning our basic systems. More

 

Experts find mangroves can slow surge

(CNS): Evidence from the latest scientific research suggests that mangroves can reduce the height of wind and swell waves over relatively short distance. According to a report by the Nature Conservancy and Wetlands International wave height can be reduced by as much as 66% over 100 metres of mangroves.

With coastal populations particularly vulnerable to the impacts of extreme events such as storms and hurricanes researchers say mangrove forests can be used as a tool in coastal defence strategies making their conservation a key part of protection. Researchers say that more work needs to be done to better understand the role they can play in defending coasts.


While Cayman does provide for some protection of mangrove buffers under the planning regulations, the plant is still persistently removed in the face of development. This was evidence in 2010 when more than 370,000 sq.ft of costal mangrove was ripped up by the developer of the Ritz Carlton on land earmarked for the Dragon Bay development.

Michael Ryan was granted permission to rip out the mangrove more than two years ago but no development has taken place on the site. In addition the promised replenishment programme has also failed to materialize.

In this new report by the environmental researchers, the importance of dense healthy mangrove to protecting coastal areas from storms has been highlighted as the experts say the plant reduces the wave energy.

“While mangrove forests are usually found on shores with little incoming wave energy, they may receive larger waves during storms, hurricanes and periods of high winds. Large wind and swell waves can cause flooding and damage to coastal infrastructure. By reducing wave energy and height, mangroves can potentially reduce associated damage,” the authors of the new report state. More

 

Biochar Promises Bevy of Benefits for People and Planet

It’s hard to attend any kind of energy or sustainability conference these days without needing to pop a Xanax, but at the 2012 US Biochar Conference , held this week in Sonoma County, California, excitement trumped angst handily. That’s because biochar is a simple technology with the potential to ameliorate no fewer than five dire global crises –topsoil depletion, nitrogen runoff, solid waste disposal, drought and, drum roll please…climate change.

Biochar is essentially charcoal that is ground up and incorporated as a soil amendment. It’s made by slowly burning anything from walnut husks to dead tree limbs to poop – just put that feedstock into a simple biochar stove (or bury it underground), light up and presto, you’ve got gas and charcoal, two valuable products for farmers grappling with high energy prices and poor soil fertility.

Long the province of farmers and gardeners, biochar is now attracting the attention of the climate change community for its massive carbon sequestration potential. Of the ten finalists for the Virgin Earth Challenge’s $25 million prize for a proven carbon capture technology, three are biochar companies.

Climate activists are fans of technologies like renewable energy that are carbon neutral -- that is, they don’t add any more friggin’ CO2 to the atmosphere. But carbon neutrality alone won’t prevent us from reaching the dreaded tipping point climate scientist James Hansen warns of . According to Hansen, even if all fossil fuel emissions cease in 2015, we’ll still be above the safe limit of 350 ppm until the end of the century (we’re currently at 395 ppm, and CO2 has a long shelf life). That means, Hansen and a growing number of climate scientists and activists agree, we need to scale up carbon negative technologies that suck CO2 out of the atmosphere. Enter biochar which, alongside reforestation, grasslands restoration and regenerative agriculture techniques, can turn dust bowls into rich, lush carbon sinks. According to the Climate Trust , biochar has the potential to sequester 12% of the world’s current GHG emissions. More



 

Rising seas force flood of activity

A new analysis of worldwide temperatures over the past 60 years has found more evidence that global warming is already upon us, and is responsible for extreme heat waves.

Naturally, this refocuses attention on the current U.S. drought. Left out of the discussion is another, equally serious and already pressing consequence of human-induced climate change: sea-level rise.

With oceans expanding from the heat and with glaciers large and small melting away, sea levels have climbed more than 8 inches since 1880, and the current rate is about an inch and a quarter every decade.

One hot spot is the East Coast, where the land is sinking and nearby ocean currents are slowing, causing the water to rise faster. From Cape Hatteras, N.C., up through Cape Cod, Mass., in the past half century, the speed of increase in water level has been three to four times the global average. Yet the North Carolina legislature has essentially banned relevant state agencies from taking projections of accelerating sea-level rises into account in policy making.

Such shortsightedness is not only irrational, it’s foolish. By 2030, in many places on the U.S. coast, sea level rise due to global warming will have more than doubled the risk of floods 4 feet or more over high tide. Lands below this 4-foot mark are now home to 5 million Americans, as well as vital infrastructure.

Not all public officials have their heads in the dampening sand. Their actions fall into three broad categories: protection, accommodation and retreat.

Protective strategies include building or reinforcing structures such as levees, dikes and sea walls and also developing soft defenses such as marshes and beaches.

Accommodation means remodeling buildings and houses in areas prone to more flooding. More

 

Climate of Failure

The heady days of early 2009, when advocates for global action on climate change anticipated world leaders gathering later that year around a conference table in Copenhagen to reach a global agreement, are but a distant memory. Today, with many of these same leaders focusing their attention on jumpstarting economic growth, environmental issues have taken a back seat. For environmentalists, it may seem that climate policy has dropped from the political agenda altogether.

Environmentalists are just now waking up to the reality that if we're going to stop global warming, we're going to have to be a lot more politically savvy.

They're right. The world's biggest emitters have reached a consensus of sorts, but not the one hoped for in Copenhagen. In the United States, President Barack Obama has borrowed his energy policy -- "all of the above" -- from the Republicans. Europe has dithered on any further commitments to emissions reductions as governments have been completely consumed by the euro crisis. China and India have used the follow-on conferences to Copenhagen, held in Durban and Cancun, to decisively push international climate negotiations into the long weeds. Leaders' attention to climate policy is not coming back -- at least not in any form comparable to the plans being discussed just a few years ago.

Copenhagen will likely be remembered as the moment when advocates for action lost their innocence. For more than a decade, expectations had been raised for a grand global bargain to put a price on carbon that would compel a major reduction in greenhouse-gas emissions -- notably carbon dioxide -- over the coming decades. To understand why this bargain failed requires a basic understanding of where carbon dioxide comes from and how it is reduced. A very simple but powerful framework for such an understanding was proposed in the 1980s by Japanese scientist Yoichi Kaya. Kaya explained that future carbon dioxide emissions would be the product of four factors: population, economic activity, how we obtain our energy, and how we use that energy.

We can simplify these four factors even further. Population and income together are simply GDP, or aggregate economic activity, and the production and consumption of energy reflect the technologies of energy supply and demand. The resulting Kaya Identity -- as his equation has come to be called -- simply says:

Emissions = GDP x Technology

With this simple equation before us, we can see the fundamental challenge to reducing emissions: A rising GDP, all else equal, leads to more emissions. But if there is one ideological commitment that unites nations and people around the world in the early 21st century, it is that GDP growth is non-negotiable. Right now, leaders on six different continents are focused on efforts to grow GDP, and with it jobs and wealth. They're not as worried about emissions. More

 

Reducing Dependence on Fossil Fuels Essential for Sustainable Progress in Small Island Developing States, Says UN Secretary-General

Small Island Developing States (SIDS) need to free themselves from dependence on fossil fuel imports and transform their energy sectors to encompass modern, efficient, clean and renewable sources of energy, Secretary-General Ban Ki-moon said in a message to an audience of prime ministers, ministers, international experts, civil society leaders and business executives at the Barbados Conference today.

Sustainable development is not possible without sustainable energy, the Secretary-General continued in his message to the conference Achieving Sustainable Energy for All in Small Island Developing States, convened by the Government of Barbados and the United Nations Development Programme (UNDP).

The worlds appetite for energy continues to grow, and the global thermostat continues to rise. My vision is a world with universal energy access; a doubling of the global rate of improvement in energy efficiency; and a doubling of renewable energy in our mix of fuel sources by 2030.

Small island developing states are highly dependent on imported oil and other fossil fuels for transport and electricity generation, which is a major source of economic volatility.

We know that although many Small Island Developing States are energy deficient in conventional energy, limitless potential for renewable energy and energy efficiency resides in our countries. The fundamental issue thus is how do we, as small island developing states with inherent structural problems and limited resources, convert this renewable energy potential into a tangible product that is accessible, affordable and adaptable, proclaimed Prime Minister, The Honourable Freundel Stuart in addressing delegates at the opening ceremony this morning.

In some small island states, switching to hydro, solar, geothermal or other renewable energy sources can free up to 30 percent of gross domestic product which is otherwise expended on imports of oil and refined petroleum products. The savings can be then invested into jobs in sectors such as clean energy, improved health care and education, stronger safety nets for people whose livelihoods will be affected by the phase out of fossil fuels, adaptation to climate change, and other programmes. More

 

Climate Change Is Here — And Worse Than We Thought

When I testified before the Senate in the hot summer of 1988 , I warned of the kind of future that climate change would bring to us and our planet. I painted a grim picture of the consequences of steadily increasing temperatures, driven by mankind’s use of fossil fuels.

But I have a confession to make: I was too optimistic.

My projections about increasing global temperature have been proved true. But I failed to fully explore how quickly that average rise would drive an increase in extreme weather.

In a new analysis of the past six decades of global temperatures, which will be published Monday, my colleagues and I have revealed a stunning increase in the frequency of extremely hot summers, with deeply troubling ramifications for not only our future but also for our present.

This is not a climate model or a prediction but actual observations of weather events and temperatures that have happened. Our analysis shows that it is no longer enough to say that global warming will increase the likelihood of extreme weather and to repeat the caveat that no individual weather event can be directly linked to climate change. To the contrary, our analysis shows that, for the extreme hot weather of the recent past, there is virtually no explanation other than climate change.

The deadly European heat wave of 2003, the fiery Russian heat wave of 2010 and catastrophic droughts in Texas and Oklahoma last year can each be attributed to climate change. And once the data are gathered in a few weeks’ time, it’s likely that the same will be true for the extremely hot summer the United States is suffering through right now.

These weather events are not simply an example of what climate change could bring. They are caused by climate change. The odds that natural variability created these extremes are minuscule, vanishingly small. To count on those odds would be like quitting your job and playing the lottery every morning to pay the bills.

Twenty-four years ago, I introduced the concept of “climate dice” to help distinguish the long-term trend of climate change from the natural variability of day-to-day weather. Some summers are hot, some cool. Some winters brutal, some mild. That’s natural variability.

But as the climate warms, natural variability is altered, too. In a normal climate without global warming, two sides of the die would represent cooler-than-normal weather, two sides would be normal weather, and two sides would be warmer-than-normal weather. Rolling the die again and again, or season after season, you would get an equal variation of weather over time.

But loading the die with a warming climate changes the odds. You end up with only one side cooler than normal, one side average, and four sides warmer than normal. Even with climate change, you will occasionally see cooler-than-normal summers or a typically cold winter. Don’t let that fool you.

Our new peer-reviewed study, published by the National Academy of Sciences, makes clear that while average global temperature has been steadily rising due to a warming climate (up about 1.5 degrees Fahrenheit in the past century), the extremes are actually becoming much more frequent and more intense worldwide. More