Climate change could expose volcanic regions, increase eruptions: Study

Climate change caused by humans is rapidly melting ice in volcanically active regions, which could lead to increased volcano eruptions, a study has found.

Climate change caused by humans is rapidly melting ice in volcanically active regions, which could lead to increased volcano eruptions, a study has found. The study, led by researchers at the University of Leeds in the UK, 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.

“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,” said Graeme Swindles from the School of Geography at Leeds. 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 findings, published 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.

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. (File Photo)

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 and 1850 AD, researchers said. Since the end of the Little Ice Age, a combination of natural and human caused climate warming is causing Icelandic glaciers to melt again, they 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,” Swindles said.

“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,” he said. 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. “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,” said Ivan Savov, from the School of Earth & Environment at Leeds. “Even small changes in surface pressure can alter the likelihood of eruptions at ice-covered volcanos,” said Savov.

 

Climate change may be vastly underestimated due to ocean temperature miscalculations - study

Scientists have discovered a flaw in the method used to measure past ocean temperatures which, if correct, could mean we have underestimated the rate of climate change over the past 100 million years.

According to the current methodology, the temperature of the ocean depths, and the surface of the polar ocean, was some 15C (59F) higher 100 million years ago, compared to now.

These estimates have been challenged, however, by a joint team of researchers from the French National Center for Scientific Research (CNRS) and the Swiss Federal Institute of Technology in Lausanne (EPFL).

In their study, published in Nature Communications, the team posits that ocean temperatures may have remained relatively stable throughout this period, raising serious concerns about the current level of climate change being experienced by Mother Earth.

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“If we are right, our study challenges decades of paleoclimate research,” EPFL’s Anders Meibom said. “Oceans cover 70 percent of our planet. They play a key role in the Earth's climate. Knowing the extent to which their temperatures have varied over geological time is crucial if we are to gain a fuller understanding of how they behave and to predict the consequences of current climate change more accurately.”

Researchers believe that over the last 50 years certain processes used in current methodology were overlooked. Scientists have used foraminifera, which are tiny marine fossils found in the sediment cores extracted from the ocean floor, to calculate ocean temperatures.

This is done by calculating the levels of oxygen-18 content in the calcareous shells of foraminifera. The level of oxygen-18 is dependent on the temperature of the ocean in which the foraminifera live.

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The problem now, it seems, is that all of these estimates were based on the principle that the oxygen-18 content remained constant while the fossils were in the sediment. To test this theory, the team exposed the foraminifera to high temperatures in simulated seawater that only contained oxygen-18.

The results show that “the level of oxygen-18 present in the foraminifera tests can in fact change without leaving a visible trace, thereby challenging the reliability of their use as a thermometer.”

“What appeared to be perfectly preserved fossils are in fact not,” CNRS researcher Sylvain Bernard said. This basically means that previous estimates of ocean temperatures are simply incorrect and instead of showing the aforementioned 15C-degree drop over the last 100 million years, the study notes that “these measurements simply reflect the change in oxygen-18 content in the fossil foraminifera tests.”

“This change appears to be the result of a process called re-equilibration: during sedimentation, temperatures rise by 20 to 30C, causing the foraminifera tests to re-equilibrate with the surrounding water,” the study says.

But what next? Well, Meibom says scientists will now have to revisit the ocean's paleotemperatures and “carefully quantify this re-equilibration, which has been overlooked for too long.”

The researchers say that they will now focus on a number of other marine organisms to see if they can “clearly understand what took place in the sediment over geological time.”

 

Climate change may force planes to lighten loads or stay grounded – study

The effects of climate change may extend further than melting glaciers and rising sea levels, according to a new study which says that hot temperatures may cause up to 30 percent of airplanes to be grounded in coming decades.

The study, published in the journal Climatic Change on Thursday, says that 10 to 30 percent of fully loaded airplanes may at some point be forced to adapt during the hottest part of the day. 

Those adaptations include removing fuel, cargo, or passengers, or waiting for cooler hours to fly.

 
Physicist Stephen Hawking and U.S. President Donald Trump © Reuters

The potential take-off problems would be due to the fact that as air warms, it spreads out and its density declines.

“In thinner air, wings generate less lift as a plane races along the runway. Thus, depending on the aircraft model, runway length, and other factors, at some point a packed plane may be unable to take off safely if the temperature gets too high,” Columbia University, whose researchers took part in the study, wrote in a press release. 

“Weight must be dumped, or else the flight delayed or canceled,” it continues.

The study’s authors estimate that fuel capacities and payload weights would have to be reduced as much as four percent for some aircraft.

To put those numbers in perspective, an average 160-seat aircraft would need roughly 12 or 13 less passengers to reach a four-percent weight reduction.

However, if carbon emissions were to somehow be sharply reduced in the near future, those reductions could amount to as little as 0.5 percent.

Planes with lower temperature tolerances would struggle more, according to the study. Airports which have shorter runways, or which are located in hotter parts of the world or in higher elevations will also suffer more than others.

 
© NERC / National Oceanography Centre

Airports which would be in danger in those cases include New York’s LaGuardia, which has short runways. Dubai International Airport in the United Arab Emirates would suffer due to its very high temperatures.

“Airports probably less affected because they are in temperate regions and have long runways include New York’s JFK, London Heathrow and Paris’s Charles de Gaulle,” the Columbia press release states.

In theory, the potential problems could be somewhat mitigated with new engine or body designs for aircraft, or expanded runways, according to study co-author Radley Horton, a climatologist at Columbia University’s Lamont-Doherty Earth Observatory.

However, such solutions are unlikely to be implemented, as planes are already highly engineered for efficiency, and there simply isn’t room to expand runways in major cities such as New York.

“The sooner climate can be incorporated into mid- and long-range plans, the more effective adaptation efforts can be,” said co-author Ethan Coffel, a Columbia University PhD student.

  • Published in World

Vulnerable ‘chokepoints’ threaten global food supply, warns report

Fourteen critical bottlenecks, from roads to ports to shipping lanes, are increasingly at risk from climate change, say analysts.

Increasingly vulnerable “chokepoints” are threatening the security of the global food supply, according to a new report. It identifies 14 critical locations, including the Suez canal, Black Sea ports and Brazil’s road network, almost all of which are already hit by frequent disruptions.

With climate change bringing more incidents of extreme weather, analysts at the Chatham House thinktank warn that the risk of a major disruption is growing but that little is being done to tackle the problem. Food supply interruptions in the past have caused huge spikes in prices which can spark major conflicts.

The chokepoints identified are locations through which exceptional amounts of the global food trade pass. More than half of the globe’s staple crop exports – wheat, maize, rice and soybean – have to travel along inland routes to a small number of key ports in the US, Brazil and the Black Sea. On top of this, more than half of these crops – and more than half of fertilisers – transit through at least one of the maritime chokepoints identified.

“We are talking about a huge share of global supply that could be delayed or stopped for a significant period of time,” said Laura Wellesley, one of the authors of the Chatham House report. “What is concerning is that, with climate change, we are very likely to see one or more of these chokepoint disruptions coincide with a harvest failure, and that’s when things start to get serious.”

The chokepoints are already suffering repeated disruptions, the report found. US inland waterways and railways, which carry 30% of the world’s maize and soy, were hit by flooding that halted traffic in 2016 and a 2012 heatwave that kinked rail lines and caused derailments.

The Panama canal has been hampered by drought, while the Suez canal has been closed by sandstorms and threatened by attempted terrorist bomb attacks. Brazil’s muddy roads are often closed by heavy rain, with 3,000 trucks stranded earlier in 2017, while its vital southern ports have been closed by storms and floods. The only chokepoint that has not recently been disrupted is the Straits of Gibraltar, which connects the Mediterranean with the Atlantic.

The Middle East and North Africa region is particularly vulnerable, the report found, because it has the highest dependency on food imports in the world and is encircled by maritime bottlenecks. It also depends heavily on wheat imports from the Black Sea.

In 2010, a severe heatwave in Russia badly hit the huge grain harvest, leading the government to impose an export ban. As a result, prices spiked in 2011 and this was a significant factor in the Arab Spring conflicts. Other factors were important too, said Wellesley, but she said: “At the start, it was about the price of bread.”

The risks posed by the chokepoints is rising as the international trade in food is growing but also because of global warming, according to the report. It says climate change is bringing more storms, droughts and heatwaves which can block chokepoints and also damage already ageing infrastructure. But it is also likely to fuel armed conflicts, which can also shut down the bottlenecks.

Other countries especially at risk from disruption are poorer nations reliant on imports such as Ethiopia, Kenya, Tanzania and Sudan, as well as richer nations like Japan and South Korea, according to the report.

China is also a major importer but it has done the most to mitigate its exposure to chokepoint risk, the report found. It has diversified its supply routes, for example building a railway across South America to lessen reliance on the Panama canal. Chinese companies also own and operate ports around the world.

The report recommends increased global cooperation to plan for food supply crises and more investment in crucial infrastructure. Wellesley said: “The straits of Hormuz [which Iran has threatened to close] is a really interesting example of where the energy sector is sitting up and taking notice – the food sector should be doing the same. Those same countries that rely on Hormuz to export their oil rely almost entirely on the same strait for their food supply.”

Paris climate agreement: World leaders slam Trump decision

World leaders on Thursday condemned President Trump's decision to pull out of the Paris climate agreement.

Although the president said he is willing to work for a better deal, France, Italy and Germany said in a joint statement that the accord can not be re-negotiated.

German Chancellor Angela Merkel, French President Emmanuel Macron and Italian Prime Minister Paolo Gentiloni urged allies to "speed up" efforts to fight against climate change and said they would do more to help poorer countries.

Paris City Hall was illuminated in green Thursday night following Trump's announcement.

Canadian Prime Minister Justin Trudeau took to Twitter to criticize Trump's decision, saying his country is "deeply disappointed."

"We are all custodians of this world, and that is why Canada will continue to work with the U.S. at the state level, and with other U.S. stakeholders, to address climate change and promote clean growth," Trudeau said in a statement.

British Prime Minister Theresa May's office said she "expressed her disappointment" in a phone call with Trump, and "stressed that the U.K. remained committed to the Paris Agreement."

Scotland's First Minister Nicola Sturgeon called the decision "irresponsible."

Prime Minister of Denmark Lars Rasmussen said it was a "sad day for the world."

The European Union's top climate change official echoed Rasmussen's sentiments, calling it "a sad day for the global community."

"The EU deeply regrets the unilateral decision by the Trump administration to withdraw the US from the Paris Agreement," European Union Climate Action and Energy Commissioner Miguel Arias Cañete said in a statement.

Former Mexican president Vincente Fox unleashed a tweetstorm, saying Trump has "surrendered the hopes and future of a nation."

“He’s declaring war on the planet itself,” Fox added.

Belgian Prime Minister Charles Michel also weighed in: "I condemn this brutal act. ... Leadership means fighting climate change together. Not forsaking commitment."

The 197-member climate agreement requires every country to establish ambitious targets to reduce greenhouse gasses. But those targets are largely voluntary, and Trump has already made clear that he views environmental regulations as an obstacle to his goal of creating jobs and ensuring energy independence.

Under the terms of the agreement, the earliest a nation can formally withdraw is November, 2020 — the same month Trump will run for re-election.

Earlier Thursday, Russia said it supported the Paris deal. "President (Vladimir) Putin signed this convention in Paris. Russia attaches great significance to it," Kremlin spokesman Dmitry Peskov said during a call with reporters, the Independent reported.

"At the same time, it goes without saying that the effectiveness of this convention is likely to be reduced without its key participants," he said.

Chinese Premier Li Keqiang promised to work with the EU to uphold the Paris climate accord, saying there is a "global consensus" and an "international responsibility” to fight climate change, the Associated Press reported.

"China in recent years has stayed true to its commitment,” he said in Berlin, referring to the Paris climate deal. China has been actively promoting the Paris agreement and was one of the first countries to ratify it, he said.

 

  • Published in World

Climate change: ‘human fingerprint’ found on global extreme weather

Global warming makes temperature patterns that cause heatwaves, droughts and floods across Europe, north America and Asia more likely, scientists find.

The fingerprint of human-caused climate change has been found on heatwaves, droughts and floods across the world, according to scientists.

The discovery indicates that the impacts of global warming are already being felt by society and adds further urgency to the need to cut carbon emissions. A key factor is the fast-melting Arctic, which is now strongly linked to extreme weather across Europe, Asia and north America.

Rising greenhouse gases in the atmosphere have long been expected to lead to increasing extreme weather events, as they trap extra energy in the atmosphere. But linking global warming to particular events is difficult because the climate is naturally variable.

The new work analysed a type of extreme weather event known to be caused by changes in “planetary waves” – such as California’s ongoing record drought, and recent heatwaves in the US and Russia, as well as severe floods in Pakistan in 2010.

Planetary waves are a pattern of winds, of which the jet stream is a part, that encircle the northern hemisphere in lines that undulate from the tropics to the poles. Normally, the whole wave moves eastwards but, under certain temperature conditions, the wave can halt its movement. This leaves whole regions under the same weather for extended periods, which can turn hot spells into heatwaves and wet weather into floods.

This type of extreme weather event is known to have increased in recent decades. But the new research used observations and climate models to show that the chances of the conditions needed to halt the planetary waves occurring are significantly more likely as a result of global warming.

“Human activity has been suspected of contributing to this pattern before, but now we uncover a clear fingerprint of human activity,” said Prof Michael Mann, at Pennsylvania State University in the US and who led the study published in the journal Scientific Reports.

Large scale wind patterns are largely driven by the temperature difference between the poles and the tropics. But global warming is altering this difference because the Arctic is heating up faster than lower latitudes and because land areas are heating up faster than the oceans.

Recent changes in the Arctic are particularly striking, with record low levels of ice cover and extremely unusual high temperatures. “Things in the Arctic are happening much faster than we expected,” said Prof Stefan Rahmstorf, also at PIK.

“It is not just a problem of nature conservation or polar bears, it is about a threat to human society that comes from these rapid changes,” he said. “This is because it hits us with increasing extreme events in the highly populated centres in the mid-latitudes. It also affects us through sea level rise, which is hitting shores globally. So these changes that are going on in the Arctic should concern everyone.”

Other climate research, called attribution, is increasingly able to calculate how much more likely specific extreme weather events have been made by global warming. For example, the heatwave in south-eastern Australia in February was made twice as likely by climate change, while Storm Desmond, which caused heavy flooding in the UK in 2015, was made 40% more likely.

Trump to sign order sweeping away Obama-era climate policies

U.S. President Donald Trump will sign an executive order on Tuesday to undo a slew of Obama-era climate change regulations that his administration says is hobbling oil drillers and coal miners, a move environmental groups have vowed to take to court.

The decree's main target is former President Barack Obama's Clean Power Plan, requiring states to slash carbon emissions from power plants - a critical element in helping the United States meet its commitments to a global climate change accord reached by nearly 200 countries in Paris in 2015.

The so-called "Energy Independence" order will also reverse a ban on coal leasing on federal lands, undo rules to curb methane emissions from oil and gas production, and reduce the weight of climate change and carbon emissions in policy and infrastructure permitting decisions.

"We're going to go in a different direction," a senior White House official told reporters ahead of Tuesday's order. "The previous administration devalued workers with their policies. We can protect the environment while providing people with work."

The wide-ranging order is the boldest yet in Trump’s broader push to cut environmental regulation to revive the drilling and mining industries, a promise he made repeatedly during the presidential campaign. But energy analysts and executives have questioned whether the moves will have a big effect on their industries, and environmentalists have called them reckless.

"I cannot tell you how many jobs the executive order is going to create but I can tell you that it provides confidence in this administration’s commitment to the coal industry," Kentucky Coal Association president Tyler White told Reuters.

Trump will sign the order at the Environmental Protection Agency with Administrator Scott Pruitt, Interior Secretary Ryan Zinke and Energy Secretary Rick Perry on Tuesday afternoon.

U.S. presidents have aimed to reduce U.S. dependence on foreign oil since the Arab oil embargo of the 1970s, which triggered soaring prices. But the United States still imports about 7.9 million barrels of crude oil a day, almost enough meet total oil demand in Japan and India combined.

'ASSAULT ON AMERICAN VALUES'

Environmental groups hurled scorn on Trump's order, arguing it is dangerous and goes against the broader global trend toward cleaner energy technologies.

"These actions are an assault on American values and they endanger the health, safety and prosperity of every American," said billionaire environmental activist Tom Steyer, the head of activist group NextGen Climate.

Green group Earthjustice was one of many organizations that said it will fight the order both in and out of court. "This order ignores the law and scientific reality," said its president, Trip Van Noppen.

An overwhelming majority of scientists believe that human use of oil and coal for energy is a main driver of climate change, causing a damaging rise in sea levels, droughts, and more frequent violent storms.

Trump and several members of his administration, however, have doubts about climate change, and Trump promised during his campaign to pull the United States out of the Paris climate accord, arguing it would hurt U.S. business.

Since being elected Trump has been mum on the Paris deal and the executive order does not address it.

Christiana Figueres, former executive secretary of the United Nations Framework Convention on Climate Change who helped broker the Paris accord, lamented Trump's order.

"Trying to make fossil fuels remain competitive in the face of a booming clean renewable power sector, with the clean air and plentiful jobs it continues to generate, is going against the flow of economics," she said.

The order will direct the EPA to start a formal "review" process to undo the Clean Power Plan, which was introduced by Obama in 2014 but was never implemented in part because of legal challenges brought by Republican-controlled states.

The Clean Power Plan required states to collectively cut carbon emissions from power plants by 32 percent below 2005 levels by 2030.

Trump’s order lifts the Interior Department's Bureau of Land Management's temporary ban on coal leasing on federal property put in place by Obama in 2016 as part of a review to study the program's impact on climate change and ensure royalty revenues were fair to taxpayers.

It also asks federal agencies to discount the cost of carbon in policy decisions and the weight of climate change considerations in infrastructure permitting, and reverses rules limiting methane leakage from oil and gas facilities.

  • Published in World

Global warming: Humans responsible for 60% loss of sea ice, study shows

That human activity is a cause of global warming and changing temperatures is a fact that cannot be debated, but until now, scientists had little clue as to what was the extent of damage due to human intervention.

That human activity is a cause of global warming and changing temperatures is a fact that cannot be debated, but until now, scientists had little clue as to what was the extent of damage due to human intervention. A paper published in Nature, based on model simulations of different climate conditions, shows that humans may be responsible for 50-70% change in climate conditions, leading to melting of ice at the Arctic sea. Although the study absolved humans for air flow changes, 70% of which, it said, is due to natural variability, it pointed that 60% of sea ice decline since 1979 was caused by summer-time changes in atmospheric circulation.

While the study is expected to change how we observe climate change, it will also get us to alter our future predictions. With Arctic ice depleting fast—in January it was 1.26 million square kilometres, which was 8.6% below the 1981–2010 average—global warming would need coordinated action from governments. Policy turns in the US—Republicans have presented a bill in the Congress to do away with the country’s Environmental Protection Agency—will end up harming the environment. With global warming accompanying industrialisation, countries would need a concerted approach to tackle its ill-effects.

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