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Author Topic: Pluto in Cap, the climate, ecology and environment topic  (Read 126495 times)
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« Reply #1695 on: Jul 29, 2015, 05:18 AM »

July 28, 2015

Data indicates polar shifts could be linked to South Africa

by Chuck Bednar
Red Orbit

For the first time, researchers have recovered a magnetic field from ancient minerals from the Iron Age in southern Africa, and the information has helped them discover that the area of the Earth’s core beneath this region could play a key role in reversals of the planet's magnetic poles.

The study, which appears in the latest edition of the journal Nature Communications, used the measurements collected by University of Rochester geophysicist John Tarduno and colleagues from Witwatersrand University and Kwa-Zulu Natal University in South Africa, along with the ongoing weakening of Earth's magnetic field during an analysis of polar reversals.

Such reversals of the North and South Poles have taken place at irregular points throughout the planet’s history, with the last one occurring about 800,000 years ago. The researchers noted that once a reversal starts, it can take up to 15,000 years to complete, and the core region beneath southern Africa may have been the origin site of some of these events.

Tarduno’s team said that while it has long been believed that polar reversals started at random locations, the data they collected from five sites along the border separating South Africa from Botswana and Zimbabwe indicates that this might not actually be the case after all.

Collecting the data from burnt ancient villages

According to study co-author Rory D. Cottrell, a scientist in the UR Paleomagnetism Research Lab and the Department of Earth & Environmental Sciences, the agricultural populations living throughout southern Africa during the Iron Age lived in semi-permanent villages. They based their economy on herding cattle, sheep, and goats, and cultivating millet, beans, and peas.

These villages consisted of mud huts, grain bins, and animal kraals, and during times of sustained drought, poor growing seasons and unexpected cattle deaths, the villages would be burned as part of a ritualistic cleansing. These burnt features enable researchers “a snap-shot look at the Earth’s magnetic field throughout the past 2000 years,” Cottrell explained via email.

“The fires were hot enough to reset magnetic minerals (primarily magnetite) above their Curie Temperature,” or the temperature where a material’s magnetic characteristics change from being unable to retain a permanent magnetic field to “freezing” the magnetic field as the material cools down. “We sampled burnt features from localities in southern Africa to look at what magnetic fields were recorded for different time periods throughout the Iron Age of southern Africa.”

The Earth’s magnetic field has been decreasing in dipole intensity for the past 160 years. The study authors attributed this observed 16 percent decrease in field strength to the weakening field in the area known as the South Atlantic Anomaly, which stretches from the part of Africa where the research took place, all the way to South America and beyond.

Findings may reflect the South Atlantic Anomaly’s longevity

While Cottrell noted that these changes (which are also called secular variation of the magnetic field) “are not uncommon,” there has been speculation that the planet is in the beginning stages of a field reversal. In a statement, Tarduno pointed out that this is only speculative at this point, as weakening magnetic fields can recover without leading to a complete polar reversal.

The researchers’ analysis of burnt structures in southern Africa revealed that there was “more change in magnetic field direction and intensity than has been seen over the last 160 years. This may speak to the longevity of the South Atlantic Anomaly, how it has changed through time,” Cottrell said. Based on models of magnetic observatory measurements, they found that this area has fluctuated magnetically in terms of both size and intensity over the past century.

“Imagine a cup full of sharpened pencils,” he explained. “Each hemisphere has their pencils generally pointing in a single direction (into the cup in the northern hemisphere, out of the cup in the southern hemisphere). Each pencil represents the magnetic field vector at a particular locality at Earth's surface. At the SAA, there [are a] number of pencils pointed in the wrong direction. So when you add all of the pencil vectors together, it is overall a smaller length (oppositely pointed pencils will effectively cancel each other out).”

“It is thought that the weak field at the SAA is related to core-flux expulsions, and these core-flux expulsions may be related to the large low shear velocity provinces (LLSVP) located at the core-mantle boundary,” Cottrell added. “The dipole field at the core-mantle boundary has lobes of lower field values (green blobs) near the edges of the LLSVP. Changing (growing) core-flux expulsions may be a focal point for magnetic dipole reversals.”


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« Reply #1696 on: Jul 29, 2015, 06:43 AM »

Ban neonicotinoids now – to avert another silent spring

George Monbiot

This pesticide is destroying life across the natural world: the evidence cannot be denied. Only a global moratorium will stop it

28 July 2014 20.27 BST
Guardian

Here’s our choice. We wait and see if a class of powerful pesticides, made by Bayer and Syngenta, is indeed pushing entire ecosystems to oblivion, or suspend their use while proper trials are conducted. The natural world versus two chemical companies: how hard can this be?

Papers published over the past few weeks suggest that these neonicotinoids, pesticides implicated in killing or disabling bees, have similar effects on much of life on Earth. On land and in water, these neurotoxins appear to be degrading entire food chains. Licensed before sufficient tests were conducted, they are now the world’s most widely used pesticides. We are just beginning to understand what we’ve walked into.

A paper in Nature last week showed a strong correlation between neonicotinoid concentrations and the decline of birds such as swallows, skylarks, yellowhammers, wagtails, starlings and whitethroats. It couldn’t demonstrate causation, but it was elegantly designed to exclude competing factors. The precipitous loss of insects caused by neonicotinoids is the simplest and most obvious explanation, as all these birds depend on insects to feed their young. Where the chemical was heavily used, bird populations fell by 3.5% a year; where it was not, they held up. At this rate, it doesn’t take long to engineer a world without song.

Another paper reports that residues of neonicotinoids were found in all the soil samples the researchers took: these chemicals are highly persistent. Sold to farmers as precise and targeted, they are some of the least discriminate pesticides ever produced. When used to treat seeds, just 5% is absorbed by the plant; the rest soaks into the soil, with potentially lethal impacts on the animals that maintain its structure and fertility.

They are also water soluble. Recent papers suggest a collapse in the diversity and abundance of invertebrates in water running off farms where neonicotinoids are used. Mayflies and caddis flies, essential to the survival of many aquatic ecosystems, are especially vulnerable.

Another new paper provides compelling evidence linking these chemicals to colony collapse disorder: the sudden disappearance of honey bee colonies that’s now trashing the livelihoods of beekeepers in the US. Half the colonies exposed to neonicotinoids disappeared in the course of one winter; none of the untreated swarms vanished.

Worldwide contamination, indiscriminately wiping out wild animals, including those on which farming depends: these are the findings of an analysis of 800 scientific papers, also just published. How much more obvious does the case for action need to be?

Sure, there is plenty that we don’t yet know. We know almost nothing about the long-term, cumulative effects of these chemicals, or about what neonicotinoids do to birds that eat contaminated seeds, to mammal and amphibian populations, to coral reefs or marine life of any kind. Governments went into it blind, approving neonicotinoids before they had even a fraction of the necessary knowledge.

Far from being essential to food production, these pesticides are a serious threat to food supplies, through their likely impacts on bees and soil animals. They are well designed for lazy farming, but their advantages vanish in the face of more sophisticated methods such as integrated pest management. The only sensible response to the little we know so far is a global moratorium pending further research for all purposes except the control of human diseases.

In August 1962, after extracts from Rachel Carson’s book Silent Spring were published, President Kennedy launched a commission to investigate the impacts of the pesticide DDT. Within 10 years it was banned from use in the US, except for public health emergencies.

This was despite lawsuits and a massive lobbying and disinformation campaign by the chemicals industry. Alongside the usual accusations of hysteria and other alleged female pathologies, it suggested that Carson was seeking to destroy US farming on behalf of the Soviet Union. The smears continue to this day. Corporate front groups concocted a myth that DDT was banned worldwide as a result of Carson’s book, causing the deaths of millions through malaria. In fact the DDT ban (still in place through the Stockholm convention) is for agricultural purposes but not disease control. DDT would soon have become useless against malaria had it continued to be used by farmers: the wider their exposure, the more quickly mosquitoes become resistant. Kennedy and his successors held firm.

Compare this with the British government’s response to attempts to control neonicotinoids. It threw everything it had against an EU proposal to suspend their use on flowering crops. Owen Paterson, the worst environment secretary this country has ever suffered – who was struck down by the Curse of Monbiot on Monday night in the cabinet reshuffle – wrote privately to Syngenta to reassure the company that “our efforts [to stop the suspension] will continue and intensify in the coming days”. His department commissioned a study claiming to show that bees were not being harmed. It was so flawed that no journal would take it. The lead author soon left to work for Syngenta.

The government’s chief scientist, Sir Mark Walport, made wildly misleading statements about the science and used scare tactics and emotional blackmail to try to keep the pesticides in circulation. Fortunately the government’s campaign failed, and a two-year moratorium, though limited only to certain flowering crops, came into force across the EU in December 2013.

The case for a global moratorium is just as strong, so once more the government weighs in on the wrong side. Ian Boyd, chief scientist at the environment department, sought last week to dismiss the new Nature paper. His article was so slapdash that he couldn’t even get the lead author’s name right. He insisted that there was insufficient evidence to draw conclusions. So did he announce a massive research programme to resolve the uncertainties? Did he hell. Uncertainty suits these people, and they will exploit it as ruthlessly as they can.

Will Liz Truss, the new environment secretary, champion science, not chemical companies? I would love to believe that there might be a remaining glimmer of recognition that governments exist to protect us from exploitation and destruction. Kennedy knew it, for all his faults. Like him, our politicians have a clear choice: surrender to corporate bullies or defend the living world. What will they do?


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« Reply #1697 on: Jul 29, 2015, 06:45 AM »

People's Climate March: the revolution starts here

Ricken Patel

This year’s march in November will send the most powerful message yet to world leaders the day before they meet for crucial climate talks in Paris

Wednesday 29 July 2015 08.00 BST
Guardian

Creating a world powered on clean energy to save ourselves from climate catastrophe is a central challenge of our time, and requires a revolutionary transition in our economies. We can’t wait for our leaders to solve this problem; unless they feel serious public pressure, they’ll never go far enough or fast enough. Revolutions start with people, not politicians.

To survive the 21st century, we must discover the sense of common purpose that has driven revolutionary change through history, building a mass movement to stretch what our politicians believe is possible. We must lead, not follow, and bring leaders with us.

In the years leading up to 2014, as the gap between what the science demanded and our politicians delivered widened, fatalism began to creep into parts of the climate movement. Then a handful of organisers took a major bet on the power of people – calling for the largest climate change mobilisation in history to kick-start political momentum.

And wow, did it work. The People’s Climate March in September last year was, without any doubt, a game-changer. Nearly 700,000 of us took to the streets, by far the largest climate mobilisation ever. The marches were hopeful, positive, inclusive. Amazingly, around the world, not a single person was arrested. Thousands of organisations, from environmental activists to faith groups to labour unions, came together, showing that climate change is no longer a ‘green’ issue, it’s an everyone issue now.

The impact on politicians was palpable. Dozens of top cabinet ministers actually joined the march, as well as UN secretary general Ban Ki-moon. As the roar of the crowd washed over them, I saw the realisation on their faces that they were witnessing history. At the UN summit the next day, leader after leader cited the marches and their intention to be more ambitious.

In the months that followed, experts told us that there was no way that Europe would adopt a target of “at least 40%” carbon emissions reduction by 2030. But with steady campaigning and the leadership of some of those ministers who attended the march, they did. Then the US and China came out with surprisingly strong emissions commitments, with China committing to peak their emissions by 2030 – a massive step. The momentum has continued, with a divestment movement shaming the fossil fuel industry, major corporations embracing clean energy, and the Pope bringing his massive moral credibility to bear on the issue. And the movement has flourished, with thousands of new flowers blooming, and growing direct action activism raising the moral urgency of the issue.

The UN climate summit in Paris this December will be the biggest global climate summit this decade. The national and global stages work in tandem, either dragging each other upward in ambition, or spiralling downward. We must make Paris a moment to seize and build on the momentum. A powerful way to do that would be for the entire world, for the first time, to agree to the goal of a decarbonised global economy powered by clean energy. That would send an immediate signal to clean and dirty energy investors everywhere, accelerating the energy transition that is already underway.

Hope is growing, momentum is with us, but we’ve been here before. From the Earth Summit in 1992 to the Kyoto Protocol in 1997, the world has surged forward in the past, only to be knocked back by the toxic politics of the fossil fuel lobby with its junk science and well-funded climate denialism. Each time, the gap between the action we’re taking and the action our survival requires widens. We need a movement that is built to last, built to win and keep winning, over decades to come.

That’s why, on 29 November, the day before world leaders converge in Paris, people will come together again in the streets for the global People’s Climate March – to break last year’s record for the largest climate change mobilisation in history. In thousands of cities and towns across the planet, we’ll gather or march for our communities and those already at risk from climate change, for the future of our children and grandchildren, and for a safer world powered by clean energy. We’ll show politicians that this is a movement that is here to stay and growing fast. And we’ll inspire others to join this ‘open source’ movement with no gatekeepers, no permissions needed – everyone is invited, not just to participate, but to organise and to lead. Because for the climate revolution to change everything, we need everyone.

On 29 November, we march!

    Ricken Patel is founding president and executive director of Avaaz, the world’s largest global civic movement with 42 million members online. Sign up for the global People’s Climate March in November here.


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« Reply #1698 on: Jul 29, 2015, 06:48 AM »

Climate change trifecta exacerbates urban, coastal flooding

Storm surge, high rainfall, and rising sea levels put low-lying US coastal cities at risk of devastating floods, researchers say.

By Beatrice Gitau, Staff writer July 28, 2015   

The biggest cities in the United States may be at far greater risk of experiencing serious flooding in decades to come than previously believed thanks to a so-called triple threat associated with climate change.

Elevated water levels, heavy rainfall, and moderate storm surge that blocks or slows down drainage have been identified in a new study as the three main reasons behind flooding for much of the cities located in the coastal US, from New York and San Francisco to Boston and Galveston, Texas.

"Nearly 40 percent of the US population resides in coastal counties," said study lead author Thomas Wahl of the University of South Florida College of Marine Science and the University of Siegen in Germany in a statement on Monday. "Flooding can have devastating impacts for these low-lying, densely populated and heavily developed regions and have wide-ranging social, economic and environmental consequences."
Recommended: Climate change: Is your opinion informed by science? Take our quiz!

Using data that reached back into the 1950s, and some data from the beginning 20th century for some sites, the researchers determined that the risk for compound flooding was higher for cities along the Atlantic and Gulf coasts than for those on the Pacific coast.

In the case of New York City, the authors determine that the increase in compound events is due to storm surge weather patterns that also favor heavy rainfall, as opposed to weather events primarily driven by heavy rainfall accompanied by storm surges.

They concluded that “the complex interplay between storm surge and precipitation can lead to, or exacerbate, the impacts of flooding in coastal zones through multiple mechanisms.”

The main idea of the study, published Monday in the journal Nature Climate Change, was to “raise awareness that those kinds of events exist” and are dangerous, Mr. Wahl told Climate Central. So far, “we have pretty much ignored them.”

Many cities have already started thinking about ways to address increased potential for flooding. In Texas, which saw devastating floods in May, cities have been curbing development around waterways and reconsidering building codes, as The Christian Science Monitor's Pete Spotts reported this spring.


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« Reply #1699 on: Jul 30, 2015, 05:36 AM »

Obama will use veto to defend climate change plan if necessary

President will use all powers available to push through Clean Power Plan to cut carbon emissions from power stations, says White House

Suzanne Goldenberg
Thursday 30 July 2015 12.07 BST
Guardian

Barack Obama will use all of his powers – including his veto – to defend his plan to fight climate change, the White House said, on the eve of new rules cutting carbon pollution from power plants.

Obama is expected to unveil the new rules as early as Monday, according to those familiar with the Environmental Protection Agency (EPA) plan.

The final version will give states and electricity companies an extra two years – until 2022 – before they need to start cutting greenhouse gas emissions.

The delay was seen as an attempt to defuse opposition from Republicans in Congress and industry to the rules.

But the White House said on Wednesday it was still gearing up to do battle over the new rules.

“When it comes to the Clean Power Plan, let me say this: We will not back down. We will finalise a stronger rule. We will veto ideological riders to stop this plan and undercut our bedrock environmental laws, and we will move forward on behalf of the American people with the vision set forward by the president,” Denis McDonough, the White House chief of staff, said on Wednesday.

He said the time lag would not weaken the power plant rules or stop the US from meeting its global commitments to fight climate change.

Power plants are the single largest source of carbon pollution in the US. The EPA rules are critical to meeting Obama’s promise to cut greenhouse gas emissions by 26% to 28% by 2025 and, by extension, shoring up Obama’s efforts to reach a global agreement to fight climate change in Paris at the end of the year.

“Given the president’s legacy, I can’t imagine the EPA would go through this huge stakeholder effort and not follow through,” said Bill Becker, director of the National Association of Clean Air Agencies.

So far, half a dozen states including Texas and Oklahoma have declared they will not go along with the EPA rules and could take the agency to court.

However, Becker said many states were already preparing to put their carbon-cutting plans in place.

Republicans in Congress this week attached riders to must-pass funding bills that would delay the EPA rules or block them entirely.

Meanwhile, power companies, especially those that rely heavily on coal, claim the EPA rules would drive up household electricity bills.

McDonough said the opposition came straight from the “well-worn playbook of scare tactics”, but he said the White House would not retreat. “There is no doubt we will be focused on all this and be forced to battle back.”

The White House official also dismissed fears the EPA delay would weaken efforts to fight climate change.

After receiving more than 4.3 million public comments – the most ever to any environmental rule – the EPA is now expected to give states until 2022 to start cutting emissions, according to those familiar with the final rule.

Under the original draft, states were required to submit an initial carbon-cutting plan by September 2016. That deadline has now been extended into 2018.

The agency is also believed to have reduced targets for some states, in the hopes of getting more support later on.

The EPA is believed to have offered incentives to states that hit the original deadline – which McDonough said would ultimately strengthen the rules.

“It will be stronger in many ways than the proposed rule put forward by the EPA by encouraging rapid deployment of the cleanest form of energy,” McDonough told a forum hosted by the New Republic and the Center for American Progress.

However, some campaign groups were openly concerned about the time lag. Ken Kimmell, the president of the Union of Concerned Scientists, said the states did not need more time to put their plans in place. “States are already on track to cut their emissions through actions they’ve put in place,” he said.

“If the EPA does decide to delay compliance timelines, I’ll be looking for assurance that the overall emission reductions achieved by the rule stay strong, early action by states is incentivized, and any delay won’t jeopardize the US’s 2025 international commitment.”

The American Lung Association, which has been a solid supporter of the EPA rules, said it was reassured by reports of incentives for states to act quickly. “The final plan ... appears to be a robust approach to reduce carbon pollution from power plants,” said CEO Harold Wimmer.


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« Reply #1700 on: Jul 30, 2015, 05:38 AM »

World Bank rejects energy industry notion that coal can cure poverty

World Bank’s climate change envoy: ‘We need to wean ourselves off coal’
Bank has stopped funding new coal projects except in ‘rare circumstances’

Suzanne Goldenberg
Wednesday 29 July 2015 20.01 BST
Guardian

The World Bank said coal was no cure for global poverty on Wednesday, rejecting a main industry argument for building new fossil fuel projects in developing countries.

In a rebuff to coal, oil and gas companies, Rachel Kyte, the World Bank climate change envoy, said continued use of coal was exacting a heavy cost on some of the world’s poorest countries, in local health impacts as well as climate change, which is imposing even graver consequences on the developing world.

“In general globally we need to wean ourselves off coal,” Kyte told an event in Washington hosted by the New Republic and the Center for American Progress. “There is a huge social cost to coal and a huge social cost to fossil fuels … if you want to be able to breathe clean air.”

Coal, oil and gas companies have pushed back against efforts to fight climate change by arguing fossil fuels are a cure to “energy poverty”, which is holding back developing countries.

Peabody Energy, the world’s biggest privately held coal company, went so far as to claim that coal would have prevented the spread of the Ebola virus.

However, Kyte said that when it came to lifting countries out of poverty, coal was part of the problem – and not part of a broader solution.

“Do I think coal is the solution to poverty? There are more than 1 billion people today who have no access to energy,” Kyte said. Hooking them up to a coal-fired grid would not on its own wreck the planet, she went on.

But Kyte added: “If they all had access to coal-fired power tomorrow their respiratory illness rates would go up, etc, etc … We need to extend access to energy to the poor and we need to do it the cleanest way possible because the social costs of coal are uncounted and damaging, just as the global emissions count is damaging as well.”

The World Bank sees climate change as a driver of poverty, threatening decades of development.

The international lender has strongly backed efforts to reach a deal in Paris at the end of the year that would limit warming to a rise of 2C (3.6F).

However, even that deal would not do enough to avoid severe consequences for some of the world’s poorest countries, Kyte said.

“Two degrees is not benign,” she said. “It is where we put the line in the sand.”

Fossil fuel companies have pushed back against the notion that climate change is a driver of poverty, arguing instead that the low global prices for coal and oil are a benefit for poor countries.

Peabody launched a global public relations offensive around the notion of “energy poverty”, trying to rebrand the dirtiest of fossil fuels as a poverty cure. Spokesmen for Shell have called efforts to cut use of fossil fuels in developing countries “energy colonialism”.

The World Bank stopped funding new coal projects except in “rare circumstances” three years ago after the US, Britain and the Netherlands opposed its decision to finance a new coal-fired power plant in South Africa.

The US stopped investing in new coal-fired projects overseas in 2011, and called on lending institutions like the World Bank to do the same.

Kyte in her remarks on Wednesday left some room for the World Bank to fund future coal projects – but she made it clear it would only be in the most isolated circumstances. “We have no coal in our pipeline apart from one particularly extreme circumstance,” she said.


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« Reply #1701 on: Jul 30, 2015, 05:42 AM »

Europe's offshore wind hits record yearly high with six months still to go

Germany drives bumper year for European offshore wind in 2015, installing three times more capacity than current leader, the UK

Damian Carrington
Thursday 30 July 2015 10.10 BST
Guardian

Europe’s offshore wind power industry has set a record for its biggest ever year just six months into 2015.

The biggest factor was a huge jump in turbines in German waters connecting to the grid, with Germany installing three times more electricity-generating capacity than the continent’s current leader, the UK.
Tories to end onshore windfarm subsidies in 2016

In the first half of the year, 584 offshore wind turbines were connected, adding 2.3GW of capacity to the European electricity grid, according to new data from the European Wind Energy Association (EWEA). In total there is now 10GW of connected offshore wind, enough to power about seven million homes.

The newly connected capacity is over 50% more than was connected in the whole of 2014. But the EWEA says it expects a slower growth rate in the next 12-18 months, as a new investment cycle begins and many projects already in the pipeline begin construction.

“2015 is shaping up to be a bumper year for offshore wind,” said Kristian Ruby, the trade body’s chief policy officer. “There are three key drivers for the market this year; exponential growth in Germany, larger capacity turbines in the water and a number of projects [becoming] either fully grid connected or partially completed.”

“This year, we are going to see Germany deploy more offshore wind than the UK for the first time.” said Ruby. “It’s a real statement of intent from Germany as the energiewende (energy transition) continues to kick in. However, it is certainly too early to say that Germany will overtake the UK [before] 2020.”

Since January, Germany has installed 1.7GW, the UK 0.5GW and the Netherlands 0.1GW. In UK waters, 102 turbines were installed in the Humber Gateway, Westermost Rough and Gwynt y Môr projects.

Offshore turbines benefit from stronger winds and fewer difficulties with planning permission than onshore projects. But the heavy foundations, more difficult maintenance and grid connection cables needed make offshore wind more expensive, though costs are falling.

The UK government frequently cites its global leadership in offshore wind as evidence of its green ambitions. The UK still has about double the installed capacity of Germany, but continued German expansion could see that gap erased. The manufacturing of turbines was dominated by Germany’s Siemens, with 57% of the new capacity added in 2015.

UK ministers recently announced the end of subsidies for onshore wind farms, and the government intends to cut support for solar and biomass energy. The moves harmed the confidence of renewable energy investors but to date ministers have not indicated they will reduce subsidies for offshore wind.

Amber Rudd, energy and climate change secretary, said: “Thanks to government support the UK is the world leader in offshore wind energy – it’s part of our long term plan to foster enterprise, innovation and create jobs as we decarbonise at the lowest cost to hardworking bill payers. We want to help technologies stand on their own two feet, not encourage a reliance on public subsidies.”

Offshore wind farms are big business, with European projects worth €7.1bn (£5bn) getting final investment approval in the first half of 2015. Another €10bn is expected to be invested in offshore wind farms in the next 18 months, providing 2.2GW of capacity, according to the EWEA.

The average turbine size increased from 3.5MW in 2014 to 4.2MW in the first half of 2015 as developers preferred more powerful machines. Orders are also starting to be seen for very large 8MW turbines.

Over 9o% of the world’s offshore wind power is installed in northern Europe, with two demonstration projects off of China the next largest projects.


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« Reply #1702 on: Jul 30, 2015, 05:46 AM »

The most polluted US national parks

Air pollution in many national parks, from Yosemite to Joshua Tree and Kings Canyon, means a hike in the ‘fresh air’ is not as healthy as it seems, reports Mother Jones

Julia Lurie for Mother Jones, part of the Guardian Environment Network
Thursday 30 July 2015 12.14 BST
Guardian

It’s late summer, and Americans are flocking to the country’s national parks for some recreation and fresh air.

But a study released this week by the National Parks Conservation Association (NPCA) found that air in some of the country’s most popular parks is not so fresh – and it’s potentially hazardous. The report rated the country’s 48 parks in three categories: levels of ozone (a pollutant that can irritate or damage lungs), haziness, and the impacts of climate change on the park. Here are the 12 worst contenders (full list available here): http://www.npca.org/assets/pdf/NPCA-Polluted-Parks-July-2015.pdf

Ozone is a pollutant common in smog, and it’s particularly prevalent on hot summer days. Seventy-five percent of the parks had ozone levels between 2008 and 2012 that were “moderate” or worse, according to the federal government’s Air Quality Index. Four national parks – Sequoia, Kings Canyon, Joshua Tree, and Yosemite – regularly have “unhealthy” ozone levels, meaning that the average hiker should reduce strenuous activity and those with asthma should avoid it altogether. (You can see the air quality in your area here.)

Jobs at Sequoia and Kings Canyon national parks, including those indoors, come with pollution warnings saying that at times the air quality “may pose human health problems due to air pollution,” according to the report.

Pollution doesn’t just make visitors and employees sick; it also ruins one of the parks’ main attractions: the views. Smog affects vistas in all of the parks; on average, air pollution obstructs 50 miles from view. Here are some examples of how far visitors can see in miles today compared to “natural” levels, when air isn’t affected by human activity.

The NPCA didn’t look into specific causes of air pollution in each location, but generally, the report attributes it to the usual suspects: coal-fired power plants, cars, and industrial and agricultural emissions. Under the regional haze program, developed by the Environmental Protection Agency in 1999, states are required to implement air quality protection plans that reduce human-caused pollution in national parks. The NPCA contends that loopholes prevent power plants and other big polluters from being affected by the rules.

Ulla Reeves, the manager of the NPCA’s clean air campaign, maintains that if enforcement for the regional haze program isn’t improved, only 10% of the national parks will have clean air in 50 years. “It’s surprising and disappointing that parks don’t have the clean air that we assume them to have and that they must have under the law.”


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« Reply #1703 on: Jul 30, 2015, 06:52 AM »

Global population set to hit 9.7 billion people by 2050 despite fall in fertility

Predicted increase of 2.4 billion will complicate efforts to stamp out poverty, inequality and hunger and place further strain on health and education systems

Sam Jones and Mark Anderson
Wednesday 29 July 2015 17.31 BST
Guardian

Despite a continuing slowdown in the rate of population growth, it is “almost inevitable” that the number of people on the planet will rise from 7.3 billion today to 9.7 billion in 2050, according to the latest UN projections.

Ten years ago, the world population was growing by 1.24% annually; today, the percentage has dropped to 1.18% – or roughly another 83 million people a year. The overall growth rate, which peaked in the late 1960s, has been falling steadily since the 1970s.

The UN report attributes the slowdown to the near-global decline in fertility rates – measured as the average number of children born to a woman over her lifetime – even in Africa, where the rates remain the highest.

However, that fall is being offset by countries in which populations are already large, or where high numbers of children are born. According to the study, nine countries will account for half the world’s population growth between now and 2050: India, Nigeria, Pakistan, the Democratic Republic of Congo, Ethiopia, Tanzania, the US, Indonesia and Uganda.

“Continued population growth until 2050 is almost inevitable, even if the decline of fertility accelerates,” says the report, World Population Prospects: the 2015 revision.

“There is an 80% probability that the population of the world will be between 8.4 and 8.6 billion in 2030, between 9.4 and 10 billion in 2050 and between 10 and 12.5 billion in 2100.”

By 2050, six countries – China, India, Indonesia, Nigeria, Pakistan and the US – are expected to have populations of more than 300 million.

The report suggests that Africa alone will drive more than half of the world’s population growth over the next 35 years, during which time the population of 28 of the continent’s countries will more than double. It is predicted that by 2050, Nigeria’s population will surpass that of the US, making the west African nation the third most populous country in the world.

If current birthrate trends persist, Africa, which contains 27 of the world’s 48 least developed countries, will be the only major area still experiencing substantial population growth after 2050. Consequently, its share of the global population is forecast to rise to 25% in 2050 and 39% by 2100. Asia’s share, meanwhile, will fall to 54% in 2050 and 44% in 2100.

“Regardless of the uncertainty surrounding future trends in fertility in Africa, the large number of young people currently on the continent who will reach adulthood in the coming years and have children of their own, ensures that the region will play a central role in shaping the size and distribution of the world’s population over the coming decades,” says the report.

John Wilmoth, director of the population division in the UN’s department of economic and social affairs, said the new projections laid bare the scale of the task facing the world as it prepares to agree the development framework for the next 15 years.

“The concentration of population growth in the poorest countries presents its own set of challenges, making it more difficult to eradicate poverty and inequality, to combat hunger and malnutrition, and to expand educational enrolment and health systems, all of which are crucial to the success of the new sustainable development agenda,” he said.

Wilmoth explained that although population growth rate had declined “gradually but steadily” since the 1970s, it had done so at different speeds in different parts of the world.

“Africa is currently the region of the world where population growth is still rather rapid due to continued high levels of fertility, but even there we see the sorts of changes that were predicted and expected in the sense that, once populations start to have a higher level of life expectancy, they also come to realise that there’s not the same need to produce as many children,” he said.

“With increasing child survival, it just doesn’t make as much sense to have such large families as it did in the past.”

China, the world’s most populous country with 1.4 billion people, is expected to be overtaken by India (1.3 billion) within the next seven years. From 2030, when its population is projected to reach 1.5 billion, India is likely to experience several decades of growth. China, on the other hand, is set to experience a slight decrease after the 2030s.

Of all the world’s major regions, only Europe can expect a steady decline in its population over the remainder of this century, with its total inhabitants expected to shrink from 738 million people now to 646 million in 2100.

Almost half the people in the world (46%) live in countries with low levels of fertility, where women have fewer than 2.1 children on average during their lifetimes. Such countries include all of Europe and northern America, 20 Asian countries, 17 Latin American or Caribbean ones, three in Oceania and one in Africa.

Another 46% live in “intermediate fertility” countries – such as India, Indonesia, Pakistan, Bangladesh, Mexico and the Philippines – where women have on average between 2.1 and five children.

The remainder live in “high-fertility” countries, where fertility declines have been only limited and where the average woman has five or more children over her lifetime. All but two of the 21 “high-fertility” countries are in Africa; the largest are Nigeria, the Democratic Republic of the Congo, Tanzania, Uganda and Afghanistan.

The slowdown in population growth provoked by the overall fall in fertility will also cause the proportion of older people to increase over time: the number of older people in the world is projected to be 1.4 billion by 2030, 2.1 billion by 2050, and could rise to 3.2 billion by the turn of the next century.

In Europe, 34% of the population is predicted to be over 60 by 2050 (up from 24% today); in Latin America and the Caribbean, the proportion of people in the same age group will more than double to reach 25% by the middle of the century. The population of Africa, which has the youngest age distribution of any area, will age rapidly, with the proportion of people aged over 60 increasing from 5% today to 9% by 2050.

Although the report predicts that the global population will reach 8.5 billion in 2030, 9.7 billion in 2050 and 11.2 billion in 2100, the UN acknowledges that its predictions could be skewed by slower-than-projected declines in fertility.

It currently estimates that global fertility will fall from 2.5 children a woman in 2010-2015 to 2.4 in 2025-2030 and 2.0 in 2095-2100. Steep declines are also projected for the world’s least-developed countries, with the average dropping from 4.3 in 2010-2015 to 3.5 in 2025-2030, and 2.1 in 2095-2100.

However, should fertility rates not decline along the predicted lines – if, for example, all countries had a rate that was half a child above the medium variant – the global population in 2100 could swell to 16.6 billion people, more than five billion more than the current estimate.

“To realise the substantial reductions in fertility projected … it is essential to invest in reproductive health and family planning, particularly in the least-developed countries, so that women and couples can achieve their desired family size,” says the report.

“In 2015, the use of modern contraceptive methods in the least-developed countries was estimated at around 34% among women of reproductive age who were married or in union, and a further 22% of such women had an unmet need for family planning, meaning that they were not using any method of contraception despite a stated desire or intention to avoid or delay childbearing.”

The latest projections are based on the previous report, the 2010 round of national population censuses and recent demographic and health surveys.


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« Reply #1704 on: Jul 30, 2015, 09:00 AM »

Ocean found underneath China’s largest basin

International Business Times
30 Jul 2015 at 09:49 ET

Chinese scientists have discovered what could potentially be a massive hidden ocean underneath the Tarim basin in northwestern Xinjiang, China, the South China Morning Post reported. The basin is one of the driest places on Earth, but the amount of salt water hidden underneath could equal 10 times the amount of water found in all five of the Great Lakes located in the U.S.

Scientists have suspected that the water is a result from high, nearby mountains, and that melt water from those mountains had sipped beneath the basin. “This is a terrifying amount of water,” said professor Li Yan, who led the study at the Chinese Academy of Sciences’ Xinjiang Institute of Ecology and Geography in Urumqi, the Xinjiang capital, the South China Morning Post reported. “Never before have people dared to imagine so much water under the sand. Our definition of desert may have to change.”

The Tarim Basin is the world’s largest landlocked basins and also home to China’s biggest desert, the Takla Makan Desert, which is situated in the middle of the basin and is presumed to be the world’s second largest-shifting desert.

Li’s team had accidentally discovered the water; they had actually been looking for carbon dioxide. Carbon dioxide can be absorbed in certain regions called “carbon sinks,” and scientists study those “carbon sinks” to better understand climate change. Li’s team had discovered 10 years that carbon dioxide had been disappearing into the basin, but could not understand why. 

    There could be ocean hidden under arid #Xinjiang #China holding "terrifying amount of water" http://t.co/LdGpm5PFBR pic.twitter.com/j5cSYwP9Vc

    — Kristine Servando (@tinssoldier) July 30, 2015

The team collected over 200 underground water samples from different areas in the desert, and by comparing the amount of carbon dioxide in the samples with the amount of carbon dioxide in the melt water, they estimated the amount of water that had flown into the basin. 

Li said his team would work with other research teams to find out if similar “oceans” could potentially exist underneath other large deserts. He said that it is likely large amounts of water will be found underneath the deserts, because according to his team’s calculations, the amount of carbon the “oceans” have the potential to carry can reach a trillion tonnes, which is the same amount of “missing carbon” on the planet.


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« Reply #1705 on: Today at 05:51 AM »

Climate models are even more accurate than you thought

The difference between modeled and observed global surface temperature changes is 38% smaller than previously thought

Dana Nuccitelli
Friday 31 July 2015 11.00 BST
Guardian

Global climate models aren’t given nearly enough credit for their accurate global temperature change projections. As the 2014 IPCC report showed, observed global surface temperature changes have been within the range of climate model simulations.

Now a new study shows that the models were even more accurate than previously thought. In previous evaluations like the one done by the IPCC, climate model simulations of global surface air temperature were compared to global surface temperature observational records like HadCRUT4. However, over the oceans, HadCRUT4 uses sea surface temperatures rather than air temperatures.

Thus looking at modeled air temperatures and HadCRUT4 observations isn’t quite an apples-to-apples comparison for the oceans. As it turns out, sea surface temperatures haven’t been warming fast as marine air temperatures, so this comparison introduces a bias that makes the observations look cooler than the model simulations. In reality, the comparisons weren’t quite correct. As lead author Kevin Cowtan told me,

    We have highlighted the fact that the planet does not warm uniformly. Air temperatures warm faster than the oceans, air temperatures over land warm faster than global air temperatures. When you put a number on global warming, that number always depends on what you are measuring. And when you do a comparison, you need to ensure you are comparing the same things.

    The model projections have generally reported global air temperatures. That’s quite helpful, because we generally live in the air rather than the water. The observations, by mixing air and water temperatures, are expected to slightly underestimate the warming of the atmosphere.

The new study addresses this problem by instead blending the modeled air temperatures over land with the modeled sea surface temperatures to allow for an apples-to-apples comparison. The authors also identified another challenging issue for these model-data comparisons in the Arctic. Over sea ice, surface air temperature measurements are used, but for open ocean, sea surface temperatures are used. As co-author Michael Mann notes, as Arctic sea ice continues to melt away, this is another factor that accurate model-data comparisons must account for.

    One key complication that arises is that the observations typically extrapolate land temperatures over sea ice covered regions since the sea surface temperature is not accessible in that case. But the distribution of sea ice changes seasonally, and there is a long-term trend toward decreasing sea ice in many regions. So the observations actually represent a moving target.

When accounting for these factors, the study finds that the difference between observed and modeled temperatures since 1975 is smaller than previously believed. The models had projected a 0.226°C per decade global surface air warming trend for 1975–2014 (and 0.212°C per decade over the geographic area covered by the HadCRUT4 record). However, when matching the HadCRUT4 methods for measuring sea surface temperatures, the modeled trend is reduced to 0.196°C per decade. The observed HadCRUT4 trend is 0.170°C per decade.

So when doing an apples-to-apples comparison, the difference between modeled global temperature simulations and observations is 38% smaller than previous estimates. Additionally, as noted in a 2014 paper led by NASA GISS director Gavin Schmidt, less energy from the sun has reached the Earth’s surface than anticipated in these model simulations, both because solar activity declined more than expected, and volcanic activity was higher than expected. Ed Hawkins, another co-author of this study, wrote about this effect.

    Combined, the apparent discrepancy between observations and simulations of global temperature over the past 15 years can be partly explained by the way the comparison is done (about a third), by the incorrect radiative forcings (about a third) and the rest is either due to climate variability or because the models are slightly over sensitive on average. But, the room for the latter effect is now much smaller.

Comparison of 84 climate model simulations (using RCP8.5) against HadCRUT4 observations (black), using either air temperatures (red line and shading) or blended temperatures using the HadCRUT4 method (blue line and shading). The upper panel shows anomalies derived from the unmodified climate model results, the lower shows the results adjusted to include the effect of updated forcings from Schmidt et al. (2014).
Comparison of 84 climate model simulations (using RCP8.5) against HadCRUT4 observations (black), using either air temperatures (red line and shading) or blended temperatures using the HadCRUT4 method (blue line and shading). The upper panel shows anomalies derived from the unmodified climate model results, the lower shows the results adjusted to include the effect of updated forcings from Schmidt et al. (2014).

As Hawkins notes, the remaining discrepancy between modeled and observed temperatures may come down to climate variability; namely the fact that there has been a preponderance of La Niña events over the past decade, which have a short-term cooling influence on global surface temperatures. When there are more La Niñas, we expect temperatures to fall below the average model projection, and when there are more El Niños, we expect temperatures to be above the projection, as may be the case when 2015 breaks the temperature record.

We can’t predict changes in solar activity, volcanic eruptions, or natural ocean cycles ahead of time. If we want to evaluate the accuracy of long-term global warming model projections, we have to account for the difference between the simulated and observed changes in these factors. When the authors of this study did so, they found that climate models have very accurately projected the observed global surface warming trend.

In other words, as I discussed in my book and Denial101x lecture, climate models have proven themselves reliable in predicting long-term global surface temperature changes. In fact, even more reliable than I realized.

Denial101x climate science success stories lecture by Dana Nuccitelli: https://www.youtube.com/watch?v=Y_jKXcgR_QA

There’s a common myth that models are unreliable, often based on apples-to-oranges comparisons, like looking at satellite estimates of temperatures higher in the atmosphere versus modeled surface air temperatures. Or, some contrarians like John Christy will only consider the temperature high in the atmosphere, where satellite estimates are less reliable, and where people don’t live.

This new study has shown that when we do an apples-to-apples comparison, climate models have done a good job projecting the observed temperatures where humans live. And those models predict that unless we take serious and immediate action to reduce human carbon pollution, global warming will continue to accelerate into dangerous territory.


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« Reply #1706 on: Today at 05:55 AM »

Malawi's forests going up in smoke as tobacco industry takes heavy toll

Malawi is reliant on tobacco for 60% of foreign earnings, but while demand is falling the cost of environmental damage caused by the industry is rising

John Vidal in Kasungu
Friday 31 July 2015 07.00 BST
Guardian

For cigarette smokers and tobacco growers, the sight – and sweet smell – of the Chinkhoma auction house near Kasungu in central Malawi is heaven. Tens of thousands of metre-cubed bales of golden leaf, each with enough tobacco to make more than 50,000 cigarettes, cover the floor of a warehouse the size of three football fields.

Malawi, now the poorest country in the world according to the World Bank, depends on tobacco as a cash crop. Chinkhoma, in the heart of the tobacco-growing Central region, is where much of it is sold before being exported and made into cigarettes.

However, while tobacco is central to the economy, there is a high price to pay. The industry contributes greatly to the destruction of forests, with millions of trees required for the drying barns involved in air- and heat-curing. The cost also includes floods, changed rainfall patterns, and a reduction in food growing.

This year, bales are selling for about $200 (£128) each. This represents about three months’ labour for a smallholder farmer. The 160m tonnes of air- and heart-cured tobacco that Chinkhoma and its sister house at Limbe, outside the capital Lilongwe, are expected to sell in the next month, will earn the country about $350m.

But as people in rich countries cut back on smoking and emerging economies like the Philippines, Indonesia and Brazil place higher taxes on cigarette sales, Malawi faces declining demand for its “green gold”.

International sales have held up, but on 21 July the government hit out at anti-smoking campaigners, saying tobacco played a vital role in the development of African countries like Malawi, Zambia and Zimbabwe, and warning that the western anti-smoking lobby risked plunging some of the poorest people in the world into further economic peril.

Allan Chiyembekeza, the agriculture minister, accepted that tobacco harmed health, but said it “is not alone in causing diseases”.

    The impact of the industry is evident in the reduction of trees cut down or tobacco curing or construction of barns
    Custom Nyirenda, Malawi's principal forest officer

“Tobacco does not stand alone in this. Other habits derived from the consumption of agricultural products are dangerous. Alcohol is addictive and leads to even higher social costs than tobacco consumption, sugar added to food leads to diabetes and obesity, butter leads to increased cholesterol. We cannot accept the discrimination and we need to stand united and resist it,” said Chiyembekeza at an international tobacco meeting in Lilongwe.

According to Graham Kunimba, head of the Tobacco Association of Malawi (Tama), tobacco is a strategic crop for some African countries. In Malawi, the industry is the second largest employer, with more than 350,000 farmers and their families, 70,000 hired labourers and 10,000 people in leaf-processing factories dependent on it, he said.

“Why is the target on tobacco products and not on other products which may have a negative impact on health, including sugar? This is not done in good faith but to punish poor countries like Malawi who rely on tobacco for its economic growth,” he said. “In the end, the people who suffer most from this situation are the tobacco farmers, who support a very large part of Malawi’s agricultural production.”

Campaigns to introduce plain cigarette packets in some countries, including Britain and France, will only drive prices down further and lead to illegal sales because the packets will be easy to copy, he said.

“The manufacturers of tobacco products will no longer have an interest in supplying a product which has a brand value. This will inevitably lead to the use of cheaper tobacco and drive down the price of leaf tobacco,” he said.

Malawi devotes more than 5% of its farming land to the crop – the highest percentage globally – but its impact contributes to a deforestation rate that is the fourth fastest in the world. Most trees are cut for fuel and charcoal, but tobacco is also an important factor. In 1990, more than 47% of the country was tree-covered, but by 2010 16.9% had been lost.

The government accepts tobacco is a major driver of deforestation. “The impact of the industry on natural resources is visible in tobacco-growing districts. This is evident in the reduction of trees which have been cut … either for tobacco curing or construction of tobacco barns,” Custom Nyirenda, the principal forest officer in the ministry of natural resources, energy and mining, told Al Jazeera last week.

According to Philip Morris, manufacturer of cigarette brands like Marlboro and Benson & Hedges and one of the largest buyers of Malawian tobacco, it takes 10kg of wood to dry 1kg of tobacco.

In a statement, the company, based in Switzerland, said: “The average amount of wood needed to dry tobacco is currently 10kg of wood/kg of dry tobacco. PMI and [local NGO] Total Land Care have created cooperatives to plant more than 90m trees and bamboo on farms and communal lands, helping to reduce Malawi’s deforestation.

“Together with our suppliers we are actively promoting the introduction of rocket barns that reduce fuel-wood consumption by 40%, to below 6kg of wood/kg of dry tobacco. We aim to convert standard curing barns to improved/rocket barns in both Malawi and Mozambique by 2017, which will result in saving the equivalent of 25m trees by 2018.”

The company said that reforestation was transforming villages. “Chitoola village in the Kasungu District was bare of trees four years ago. It is unrecognisable today with its forest cover of 50,000 trees. Its residents once had to buy wood – now they sell it to others.”


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« Reply #1707 on: Today at 05:57 AM »

CS Monitor

Can forests rebound from severe drought?

Even after drought conditions subside, trees may take years to resume normal growth, say scientists.

By Joseph Dussault, Staff writer July 30, 2015   

It's no surprise that droughts can severely weaken forests. But what happens when the drought ends?

Traditionally, climate models have operated under the assumption that forests bounce back quickly from periods of extreme stress. But new research, published Thursday in the journal Science, suggests that trees may take years to resume normal growth after a period of drought.

"It's probably not too surprising that trees don't seem to recover from severe drought immediately," lead author William Anderegg told the Monitor. "A large body of plant physiological research has studied drought stress and damage, and repair of that damage is rarely observed as perfect or immediate."
Take Action:Connect with those tackling issues like global warming, clean air and water, and land conservation.

He added, "What surprised us was how widespread and pervasive this delayed recovery from drought was."

Dr. Anderegg, who studies climate change at Princeton University, found that living trees took an average of two to four years to recover post-drought. There was just one exception: California and Mediterranean regions actually grew faster after a drought.

"We don't have a clear answer as to why this was," Anderegg says. "One possibility is that these regions tended to be dominated by oak forests, and we found that oaks tended to recover relatively quickly."

Or maybe the droughts killed off some trees entirely, he theorizes, so the surviving trees had more light and nutrients available. "Without more detailed studies, we won't know for sure," he says.

Each year, forests take in about a quarter of all human carbon dioxide emissions. By absorbing CO2 and cycling oxygen back into the atmosphere, trees slow the progression of climate change. But Anderegg and colleagues found that trees take in significantly less carbon during and after drought.
Take Action:Connect with those tackling issues like global warming, clean air and water, and land conservation.

"Forests are on average still taking up carbon," Anderegg says, but that could change.

"With more intense and frequent droughts, forests could spend more time recovering, and trees may start dying en masse from drought, fire, and infestations," he explains. "This has the potential to drive forests to become carbon sources to the atmosphere, which would accelerate climate change and start a vicious cycle."

More frequent drought and recovery cycles could cause serious long-term troubles. Anderegg worries that massive forest die-offs could become common as droughts become more prevalent and severe.

"We've seen instances of this occurring around the globe in the past decade or so, and the western US has really been a hotspot of widespread tree mortality," Anderegg says. "In some areas, other tree species that are more drought-tolerant could move in, but in some areas we might lose forests altogether if it gets too hot and dry."

But awareness is an important first step. These new findings could be used to develop more accurate climatological models. And according to Anderegg, both short and long-term measures can prevent forest loss and escalating climate change.

"At the largest scale, the sooner and more effectively that we address climate change, the less risks that forests will face. This is absolutely crucial," he says.

"At a smaller scale," he adds, "we can take steps to increase the resilience of forests to changes in climate. These include actions like restoring the natural density of trees – many forests in the western US, for example, have gotten too dense due to decades of suppressing wildfires – encouraging growth and management of trees in areas where they can persist, and minimizing other stresses on forests like overgrazing and wildfires."


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