Category Archives: Climate

Warmer Atlantic widens invader’s hunting ground

Moving home: an Indo-Pacific lionfish on a reef off the North Carolina coast Image: NOAA
Moving home: an Indo-Pacific lionfish cruises on a reef off the North Carolina coast
Image: NOAA

By Tim Radford

The exotic lionfish, already a long way from the reefs of its Indo-Pacific home, is heading further north up the US coast as global warming causes big changes to ocean habitats.

LONDON, 28 September, 2014 − The venomous lionfish is on the move. This invasive species has been observed in deeper waters off the North Carolina coast since the turn of the century, but new research suggests it may now be expanding its range into the shallower levels.

Since the lionfish (Pterois volitans) is actually native to the Indo-Pacific region, it is already a long way from home. But what now gives it licence to hunt further north is warmer sea temperature.

Global warming has already begun to make huge differences to ocean habitat. The bluefin tuna is a temperate zone fish that has already been observed in Arctic waters off the coast of Greenland, and commercial species such as red mullet, a creature of the Mediterranean, has been seen in the North Sea and even in Norwegian waters.

Now researchers in the US have reported that the lionfish – an invader first observed off the Florida coast in the 1980s − is spreading through the north-west Atlantic.

Temperature is the key determinant for a fish on the move. Fisheries biologist Paula Whitfield, of the National Oceanic and Atmospheric Administration’s National Centres for Coastal Ocean Science, and colleagues report in the journal Marine Ecology Progress Series that they surveyed 40 species of fish off the reefs of North Carolina.

Tropical species

These reefs have always been home both to temperate and tropical species, at the limits of their ranges. But now the reefs are becoming more tropical − and so is the local population.

“Along the North Carolina coast, warming water temperatures may allow the expansion of tropical fish species, such as lionfish, into areas that were previously uninhabitable due to cold winter temperatures,” Whitfield says.

“The temperature thresholds collected in this study will allow us to detect and estimate fish community changes related to water temperature.”

The lionfish tends to prefer water warmer than 15.2°C, and so normally inhabits the warm currents of the deeper waters in the temperate Atlantic. It is a carnivore that seems to enjoy a wide range of prey. It makes itself at home in a wide variety of habitat, and is considered a serious threat to other species of reef fish. – Climate News Network

California burning points to more intense wildfires

Burning issue: a wildfire raging this month in California’s Yosemite National Park Image: PBJamesPhoto via Wikimedia Commons
Razed alarm: wildfire rages through part of California’s Yosemite National Park this month
Image: PBJamesPhoto via Wikimedia Commons

By Kieran Cooke

As the forest fires season peaks in the western US, a new report predicts that climate-led temperature rise will lead to millions more acres across the world being burned to the ground.

LONDON, 27 September, 2014 − Smoke from fires burning at present in northern California has been detected as far north as Canada, as thousands of firefighters battle to contain blazes that together cover nearly 300,000 acres of forest and shrub wood. And it looks like things are going to get worse.

A new report by the US-based Cost of Carbon Pollution project forecasts that such fires are going to become ever more intense in the years ahead – not just in the western US, but elsewhere round the world, and particularly in areas of southern Europe and in Australia.

The ongoing drought across much of the western US has had a serious impact on the region’s agricultural industry, and has resulted in the build-up of vast amounts of tinder-dry material on the land.

“We haven’t been out of fire season for a year and a half,” a leading fire official told the Washington Post. “There is no end in sight.”

Incidence doubles

The new report says the incidence of wildfires – unrestrained fires that burn predominantly in areas of forests, woodlands, grasslands, peat or shrubs – has doubled in the US since the 1990s.

In total, between seven and nine million acres in the US are burned as a result of wildfires every year – an area equivalent to one-and-a-half times the size of the state of Massachusetts.

“These amounts are expected to increase significantly due to climate change and other factors,” the report says. And, overall, there is likely to be a 50% increase by 2050 in the area of North America burned, with more large and potentially catastrophic wildfires.

Not only will more valuable forest be lost, the fires will also have an increasing impact on the economy − with important industries such as tourism suffering serious losses.

More and more people have been migrating to the western US. In 1960, California’s population was 15 million: it’s now nearly 40 million, and is expected to increase to 50 million by 2030. The study says the fires are already taking their toll on people’s health.

Forests and peat lands function as carbon sinks – sucking up volumes of greenhouse gases (GHGs). But the report says an increase in wildfires could mean that, in time, these areas would become net emitters of GHGs, adding to problems of global warming.

Mistaken policies

Dr Wallace Covington, director of the Ecological Restoration Institute at Northern Arizona University, is an internationally-recognised expert on forest restoration. He says that the growth in wildfires in the western US is due, to a large extent, to mistaken forest policies over the past 100 years.

Dense forests were planted, while natural fires – which form a normal part of nature’s cycle, and can regenerate growth in some trees and plants – were suppressed.

“Forests became unhealthy, and an excessive amount of fire fuel was allowed to build up,” Covington told the Climate News Network. “Natural fires can be easily controlled, but once fires spread over thousands of acres they are virtually impossible to contain.”

Covington says that climate change has exacerbated the situation. “We’re seeing wider swings from very dry to very wet conditions, and wind speeds, which fan the forest flames, have been building up across the region over recent years.”

Forest specialists at Northern Arizona University and elsewhere are now pressing for radical changes in forestry policy, including the thinning of densely-wooded areas and the reintroduction of controlled, natural fires at various times of the year. – Climate News Network

Ice melt dilutes Arctic sea’s CO2 clean-up role

Cutting edge: climate scientist Dorte Haubjerg Søgaard studies the sea ice in Greenland Image: Søren Rysgaard,  Arctic Research Centre, Aarhus University
Cutting edge: climate scientist Dorte Haubjerg Søgaard studies the sea ice in Greenland
Image: Søren Rysgaard, Arctic Research Centre, Aarhus University

By Tim Radford

New scientific research confirms that global warming is melting increasingly larger areas of Arctic sea ice − and reducing its vital function of removing CO2 from the atmosphere.

LONDON, 26 September, 2014 − The Arctic ice cap has just passed its summer minimum – and it’s the sixth lowest measure of sea ice recorded since 1978, according to scientists at the US space agency NASA.

For three decades, the shrinking Arctic ice – and the growing area of clear blue water exposed each summer – has been a cause of increasing alarm to climate scientists.

Polar seasonal changes are measured annually by NASA, but reliable satellite data goes back only to 1978, For much of the 20th century, the Arctic was part of the Cold War zone, so only Soviet naval icebreakers and US nuclear submarines took consistent measurements − and neither side published the data.

But studies of 17th and 18th century whaling ships’ logbooks and other records make it clear that the ice once stretched much further south each summer than it does today.

Steady decline

In the last 30 years, the thickness and the area of the ice have both been in steady decline, with predictions that in a few decades the Arctic Ocean could be virtually ice free by September, opening up new sea routes between Asia and Europe.

This year could have been worse, although the area of ice fell to little more than 5 million square kilometres − significantly below the 1981-2010 average of 6.22 million sq km.

“The summer started off relatively cool, and lacked the big storms or persistent winds that can break up ice and increase melting,” said Walter Meier, a research scientists at NASA’s Goddard Space Flight Centre. “Even with a relatively cool year, the ice is so much thinner than it used to be. It is more susceptible to melting.”

Warming in the Arctic is likely to affect climate patterns in the temperate zones, and the state of the polar ice has become of such concern that researchers are using ground-based and sea-based monitors to explore the physics of the phenomenon.

But there is another reason for the attention: as polar ice diminishes, so does the planet’s albedo − its ability to reflect sunlight back into space.

So, as the ice shrinks, the seas warm, making it more difficult for new ice to form. And greater exposure to sunlight increases the probability that permafrost will thaw, releasing even more greenhouse gases locked in the frozen soils.

Now researchers have found another and unexpected example of climate feedback that could affect the cycle of warming. Climate scientist Dorte Haubjerg Søgaard, of the Greenland Institute of Natural Resources and the University of Southern Denmark, and research colleagues have discovered that sea ice itself is an agency that removes carbon dioxide from the atmosphere.

That the oceans absorb the stuff, and tuck it away as calcium carbonate or other marine minerals, is old news.

“But we also thought that this did not apply to ocean areas covered by ice, because the ice was considered impenetrable,” Søgaard said. “However, new research shows that sea ice in the Arctic draws large amounts of CO2 from the atmosphere into the ocean.”

The research is published in four journals, Polar Biology, The Cryosphere, The Journal of Geophysical Research: Atmospheres and Marine Ecology Progress Series.

Two-stage pattern

The Danish research team observed a complex, two-stage pattern of gas exchange as ice floes formed off southern Greenland. They measured the role of atmospheric carbon dioxide in the formation and release of calcium carbonate crystals form in the sea ice, and kept a tally during a 71-day cycle of the carbon dioxide budget.

In the course of this complicated bit of natural cryo-chemistry, they found that some CO2 was carried deep into the ocean with dense, heavy brines, as the ice froze and some was captured by algae in the thawing ice.

They also identified a third factor: the “frost flowers” that formed on the new ice had an unexpectedly high concentration of calcium carbonate.

The profit-and-loss accounting meant that every square metre of ice effectively removed 56 milligrams of carbon from the atmosphere during the 71-day cycle. Over an area of 5 million sq km, this would represent a significant uptake.

But the real importance of the discovery is that scientists have identified yet another way in which the ice – while it is there – helps keep the Arctic cold, and yet another way in which carbon dioxide is absorbed by the oceans.

“If our results are representative, then the sea ice plays a greater role than expected, and we should take account of this in future global CO2 budgets,” Søgaard said. – Climate News Network

Croplands changed by climate’s ups and downs

Arid areas such as Patagonia have become wetter rather than drier Image: Rolf Hengel via Wikimedia Commons
Arid areas such as Patagonia have unexpectedly become wetter rather than drier
Image: Rolf Hengel via Wikimedia Commons

By Tim Radford

New research shows that the complex balance of gains and losses caused by climate change could mean more land being available for agriculture − but fewer harvests.

LONDON, 25 September, 2014 − With climate change, you win some, you lose some. New research shows that suitable new cropland could become available in the high latitudes as the world warms − but tropical regions may become less productive.

Florian Zabel and two fellow-geographers from Ludwig Maximilians University in Munich, Germany, report in the journal Public Library of Science One that they made judgments about the climate, soil and topography to suit the 16 most important food and energy crops. They then compared data for the period 1981-2010 with simulations of a warming world for the period 2071-2100.

The results looked good: in northern Canada, China and Russia, they found that a notional additional land area of 5.6 million sq km became available for crops.

Significant losses

Less happily, in the Mediterranean and sub-Saharan Africa there were significant losses of agricultural productivity – if no additional irrigation was factored in. Also, the chances of multiple harvests in tropical Brazil, Asia and Central Africa would be reduced.

Altogether, the land suitable for agriculture by 2100 would total 54 million sq km. But of this, 91% is already under cultivation.

“Much of the additional area is, however, at best only moderately suited to agricultural use, so the proportion of highly fertile land suited to agricultural use will decrease,” Dr Zabel says.

“In the context of current projections, which predict that the demand for food will double by the year 2050 as the result of population increase, our results are quite alarming.”

The Munich calculations were essentially mathematical projections based on climate models that are, in turn, based on broad conclusions of change. But what if those broad conclusions are too sweeping?

Climate researcher Peter Greve, of the Swiss Federal Institute of Technology (ETH) in Zurich, and colleagues report in Nature Geoscience that the rule of thumb for climate change – that wet regions will tend to get wetter, and already dry regions will in general become more arid – may not always hold.

So they looked at the calculations again, and began to search for trends towards increasing humidity or aridity.

In effect, they were trying to see if they could predict what should have happened in the past, so they chose two periods − 1948 to 1968, and 1984 to 2004 − and examined the patterns of change.

Clear trends

They could find no obvious trend towards either a wetter or a drier climate over about three-quarters of the land area under consideration. There were clear trends for the remaining quarter, but, once again, the answers were not simple. In about half of this land area, the dry-gets-drier, wet-gets-wetter rule seemed to hold. In the other half, the trends seemed to be contradictory.

In the past, parts of the Amazon, Central America, tropical Africa and Asia should have got wetter, but instead became less moist. Patagonia, central Australia and the US Midwest were all dry areas that became wetter.

The wet-gets-wetter rule held good for the eastern US, northern Australia and northern Eurasia, and the already dry Sahel, Arabian Peninsula and parts of central Asia and Australia became more parched.

The lesson is not that climate projections are wrong, but that climate systems are very complex. “Our results emphasise how we should not overly rely on simplifying principles to assess past developments in dryness and humidity,” Greve says. – Climate News Network

Clean urban transport can drive emissions cuts

Making public transport cleaner and more accessible can reap major benefits Image: Ilya Plekhenov via Wikimedia Commons
Making public transport cleaner and more accessible will lead to major social benefits
Image: Ilya Plekhenov via Wikimedia Commons

By Tim Radford

Researchers’ urgent message to world leaders at the UN climate summit: save 1.4 million lives and trillions of dollars by controlling vehicle pollution, improving public transport and shifting away from the car culture.

LONDON, 24 September, 2014 − Here’s a way to save $100 trillion and stop 1,700 million tonnes of carbon dioxide from getting into the atmosphere every year by 2050: cycle, walk or take public transport.

A new report by the University of California Davis and the Institute for Transportation and Development Policy (ITDP) estimates that such a policy would also prevent 1.4 million premature deaths a year from lung cancer and cardiopulmonary diseases.

The report, aimed to coincide with the current UN climate change summit in New York, sees sustainable public transport as a key factor in economic development.

Pollution  controls

However, according to parallel analysis by the International Council on Clean Transportation, the planet’s governments must also demand the strongest vehicle pollution controls and push for ultra-low sulphur fuels.

The ITDP message is, of course, one that city planners, health chiefs, traffic analysts, atmospheric scientists and environmental campaigners have been urging for decades. The difference is that the new report, called A Global High Shift Scenario, attempts to estimate the money saved, the greenhouse gases not emitted, and the lives saved by a switch from the “business-as-usual” approach to transport.

This would require governments everywhere to invest in clean, safe and swift public transport by bus and rail, and at the same time make the streets safe for cyclists and pedestrians.

If authorities also moved investment away from road construction, garages and parking lots, then enormous savings would follow over the next 35 years.

“Transportation, driven by rapid growth in car use, has been the fastest-growing source of CO2 in the world,” says Michael Replogle, ITDP’s founder and managing director for policy.

His co-author, Lew Fulton, co-director of the NextSTEPS (Sustainable Transportation Energy Pathways) programme within the Institute of Transportation Studies at the University of California Davis, adds: “The analysis shows that car-centric development will cut urban CO2 dramatically and also reduce costs, especially in rapidly expanding economies.”

Under the ITDP scenario, access to public transport would more than triple for the lowest income groups, and double for the next lowest income group. Overall, mobility tends to provide the poorest people with better access to employment and to services that will improve livelihoods.

Fulton says: “Today, and out to 2050, lower income groups will have limited access to cars in most countries under almost any scenario, so improving access to modern, clean, high-capacity public transport is crucial.”

Growing inequality

And Replogle warns: “Unmanaged growth in motor vehicle use threatens to exacerbate growing income inequality and environmental ills, while more sustainable transport delivers access for all, reducing these ills.”

Motor traffic in urban areas accounted for 2,300 megatonnes of carbon dioxide in 2010 –about a quarter of emissions from all parts of the transport sector. Rapid urbanisation in China, India and other fast-developing countries threatens to double these emissions.

Right now, the US is the world leader in carbon dioxide emissions from urban passenger transport, with 670 megatonnes a year. But the report calculates that this could be reduced to 280 megatonnes.

In China, the emissions from city transport are expected to rise from 190 megatonnes a year now to 1,100 megatonnes as the nation’s economy booms. Under the high shift scenario, this could be slashed to 650 megatonnes, with help from extensive investment in public transport.

Currently, Indian cities emit 70 megatonnes. This could rise to 540 megatonnes by 2050, but the report says that these could be contained at 350 megatonnes by addressing crucial deficiencies in India’s public transport. – Climate News Network

Investor heavyweights call for clear action on climate

Falling costs make renewables such as solar energy competitive in the US without subsidies Image: US Bureau of Land Management via Wikimedia Commons
Falling costs make renewables such as solar energy competitive in the US without subsidy
Image: US Bureau of Land Management via Wikimedia Commons

By Kieran Cooke

As a major UN climate summit gets under way in New York today, some of the world’s leading institutional investors demand clearer policies on climate change and the phasing out of fossil fuel subsidies.

LONDON, 23 September, 2014 − Many of the biggest hitters in the global financial community, together managing an eye-watering $24 trillion of investment funds, have issued a powerful warning to political leaders about the risks of failing to establish clear policy on reducing greenhouse gas emissions.

More than 340 investment concerns − ranging from Scandinavian pensions funds to institutional investors in Asia, Australia, South Africa and the US − have put their signatures to what they describe as global investors’ most comprehensive statement yet on climate change.

In particular, the investors call on government leaders to provide a “stable, reliable and economically meaningful carbon policy”, and to develop plans to phase out subsidies on fossil fuels.

They warn: “Gaps, weaknesses and delays in climate change and clean energy policies will increase the risks to our investments as a result of the physical impacts of climate change, and will increase the likelihood that more radical policy measures will be required to reduce greenhouse gas emissions.

Ambitious policies

“Stronger political leadership and more ambitious policies are needed in order for us to scale up our investments.”

Attempts to establish carbon pricing systems capable of making an impact on climate change have so far ended in failure, while oil and gas companies continue to battle against stopping fossil fuel subsidies.

The investors’ move has been welcomed by the United Nations.

Achim Steiner, head of the UN Environment Programme, said: “Investors are owners of large segments of the global economy, as well as custodians of citizens’ savings around the world. Having such a critical mass of them demand a transition to the low-carbon and green economy is exactly the signal governments need in order to move to ambitious action quickly.

“What is needed is an unprecedented re-channelling of investment from today´s economy into the low-carbon economy of tomorrow.”

The investors’ statement comes amid growing concern in the finance sector about the economic consequences of a warming world.

Last week, a commission composed of leading economists and senior political figures said the transition to a low-carbon economy was vital in order to ensure continued global economic growth.

Stranded assets

Other groups say investors who continue to put their money into fossil fuels are taking considerable risks. As governments and regulators face up to the enormity of climate change and place more restrictions on fossil fuels, such investments could become what are termed “stranded assets”.

There are also signs of a surge in low-carbon technologies, particularly in the renewable energy sector. Last week, Lazard, the asset management firm, reported that a decline in cost and increased efficiency means large wind and solar installations in the US can now, without subsidies, be cost competitive with gas-fired power.

There is also increased activity on the carbon pricing front. China, the world’s biggest emitter of greenhouse gases, recently announced it would establish a countrywide emissions trading system by 2016.

If implemented, the China carbon trading system will be the world’s biggest. The country already runs seven regional carbon trading schemes. – Climate News Network

Record CO2 levels fuel urgent calls for emissions cuts

New York traffic congestion is a stark illustration of the CO2 emissions danger Image: ILMRT via Wikimedia Commons
New York traffic congestion provides a stark reminder of the CO2 emissions danger
Image: ILMRT via Wikimedia Commons

By Tim Radford

The alarming message from international scientists to political leaders meeting at tomorrow’s UN climate summit in New York is that record global CO2 emissions this year mean “delaying action is not an option”.

LONDON, 22 September, 2014 − Global carbon dioxide emissions will this year reach a new record as power stations, cars, buses, trains, aircraft, tractors, factories, farms and cement works continue to burn fossil fuels − releasing an estimated 40 billion tonnes of the greenhouse gas into the atmosphere.

And the world’s chances of limiting global average surface warming to 2°C – an ambition agreed by the world’s political leaders in Copenhagen in 2009 − are dwindling, according to new studies published just ahead of the United Nations summit on climate change opening in New York tomorrow.

Professor Pierre Friedlingstein, Chair in Mathematical Modelling of Climate Systems at Exeter University, UK, and  a consortium of colleagues from the UK, Norway, Switzerland, Austria, Germany, the Netherlands and Australia report in Nature Geoscience that despite attempts to reduce fossil fuel dependence, greenhouse gas emissions have on average continued to grow by 2.5% per year for the last decade.

Ration exhausted

This means that, if there is a ration or quota of emitted carbon dioxide consistent with a 2°C increase, then the world has already used up two-thirds of it. And if it goes on burning fuel at the 2014 rate, then this ration will be exhausted within 30 years.

The study, part of a package of papers and reflections in Nature Geoscience and Nature Climate Change calculated to inform debate and crystallise opinion, has been widely endorsed by other climate scientists.

David Reay, professor of carbon management at the University of Edinburgh, UK, said: “If this were a bank statement, it would say our credit is running out.”

The scientists, partners in a research consortium called the Global Carbon Project, list the top four emitters of carbon dioxide: China – emissions grew by 4.2%; US – emissions increased by 2.9%, thanks to a rebound in coal consumption; India – emissions grew by 5.1%, as a result of robust economic performance; European Union – emissions actually fell by 1.8%, due to weak economic growth.

“China now emits more than the US and EU combined and has CO2 emissions per person 45% higher than the global average, exceeding even the EU average,” said one of the report’s authors, Robbie Andrew, a senior research fellow at the Centre for International Climate and Environmental Research – Oslo (Cicero), in Norway.

And co-author Glen Peters, also a senior research fellow at Cicero, said: “Globally, emissions would need sustained and unprecedented reductions of around 7% per year for a likely chance to stay within the quota.”

Corinne Le Quéré, director of the Tyndall Centre for Climate Change Research at the University of East Anglia, UK, said: “The human influence on climate change is clear. We need substantial and sustained reductions in CO2 emissions from burning fossil fuels if we are to limit climate change.

“Politicians . . . need to think very carefully about their
diminishing choices exposed by climate science”

“We are nowhere near the commitments necessary to stay below 2°C of climate change − a level that will already be challenging to manage for most countries around the world, even for rich nations. Politicians meeting in New York need to think very carefully about their diminishing choices exposed by climate science.”

Professor Friedlingstein stressed: “Delaying action is not an option. We need to act together, and act quickly if we are to stand a chance of avoiding climate change not long into the future, but within many of our own lifetimes.”

Most of the message in the Nature Geoscience paper is already familiar as scientists in Europe, Asia and the US have repeatedly stressed that even a 2°C increase in average global temperatures could have alarming consequences for hundreds of millions of people.

The timing of the publication is a reminder of the problem’s urgency, and many of the Nature Geoscience report’s authors also offer a prescription for action in the journal Nature Climate Change.

In this they try to outline ways in which the burden of reduction might be shared among the world’s nations. This is essentially a political problem that will require sustained international negotiation and argument.

Prof Myles Allen, who heads the Climate Dynamics Group at Oxford University, UK, said: “It is depressing that the immediate reaction to the news we have a limited carbon pie is discussion of how countries can slice it up. We didn’t save the ozone layer by rationing deodorant.”

Abstract goals

But David Victor, professor of international relations at the University of California San Diego, in an accompanying essay in Nature Climate Change, warns that researchers and campaigners “have focused too much scientific talent on abstract goals and not enough on understanding the practical actions that individual governments, firms and individuals would take to meet global goals”.

The New York summit is one of a series that will lead up to the UN climate change summit in Paris in 2015, and Prof Victor foresees a need for climate scientists to work with social scientists to understand better how attitudes change, and policies are decided.

He concludes: “It is highly unlikely that the Paris summit will deliver an accord that limits warming to 2°C, and hopes for that outcome in the scientific community are built on a naïve vision that science sets goals and that politicians, once they shed the scales from their eyes, will follow in lockstep.

“Awareness of what the behavioural sciences can bring suggests, as well, that the era of really important science is perhaps just beginning.” – Climate News Network

Early warning for US states in Tornado Alley

Dark destroyer: a tornado tears through Kansas, one of the US states in ‘Tornado Alley’ Image: Goodland/US National Weather Service via Wikimedia Commons
Dark destroyer: a tornado tears through Kansas, one of the US states in ‘Tornado Alley’
Image: Goodland/US National Weather Service via Wikimedia Commons

By Tim Radford

Research showing that tornadoes are gradually forming earlier in the US could help states in the frontline to prepare better to withstand the storms’ devastating effects.

LONDON, 21 September, 2014 − The terrifying whirlwinds that punctuate the mid-Western summer in the US so frequently as to earn the nickname “Tornado Alley” for the southern plains region states such as Nebraska, Kansas, Oklahoma and northern Texas are forming up to two weeks earlier than they did 60 years ago.

John Long and Paul Stoy, research scientists at Montana State University, report in the journal Geophysical Research Letters that, on average, the tornado season advanced by one week between 1954 and 2009. For many states, the shift is almost 14 days. Peak activity on average used to occur on 26 May, but this century the peak has shifted to 19 May.

On the plus side, the tornado season is also ending earlier than it did in the 1950s.

Tornadoes happen in every continent except Antarctica, but particularly in America. There are on average around 1,300 in the US every year, and on average they kill about 60 people.

They are graded according to the punch they pack: the Fujita scale of tornado rating ranges from F1, with winds at 117 kilometres per hour to 180 kph, to F5, at between 420 kph and 511 kph.

Increase in ferocity

Long and Stoy are not the first to note a change in the pattern of storms. Recently, researchers calculated that, overall, the number of tornadoes each year may be dwindling, but their ferocity seems to be on the increase.

Some researchers think climate change is a factor, but the two Montana scientists are more cautious. They say it takes a mix of topography, temperature, wind patterns and other factors to set in motion the swarms of storms that can slam into a town and wreck tens of thousands of homes in a matter of minutes.

“Observed climate trends cannot fully account for observations,” they say in the formal language demanded by science journals.

But they also point out that if the tornado season is occurring earlier in the year, then it might help individuals, local authorities, emergency services and state governments to know this, and to be prepared. – Climate News Network

Political will is only barrier to 100% renewables

Wind turbines in Germany's Rhein-Hunsrück district, a world leader in renewables Image: Markus Braun via Wikimedia Commons
Germany’s Rhein-Hunsrück district already exceeds100% electricity from renewables
Image: Markus Braun via Wikimedia Commons

By Paul Brown

A report published ahead of next week’s UN Climate Summit illustrates that poor and prosperous nations, tiny islands and great cities, can achieve all their energy needs from renewables.

LONDON, 20 September, 2014 − A new handbook shows how forward-looking communities around the world are already moving away from reliance on fossil fuels and generating their own power with 100% renewables − while also becoming more prosperous and creating jobs.

The report, How to Achieve 100% Renewable Energy, is being released today, ahead of the UN Climate Summit in New York next Tuesday (September 23), when the UN Secretary-general, Ban Ki-Moon, will call on world leaders to make new commitments to cut fossil fuel use.

The World Future Council, based in Hamburg, Germany, has issued the report to show that it is only lack of political will that is preventing the world switching away from fossil fuels. It believes that the leaders at the UN summit need to set ambitious targets and timetables to achieve the switch to renewables.

Technologies exist

Using case histories − from small islands in the Canaries to great commercial cities such as Frankfurt in Germany and Sydney in Australia − the report makes clear that the technologies to go 100% renewable exist already.

In many cases, the switch has the combined effect of saving money for the community concerned and creating jobs, making everyone more prosperous. In all cases, improvements in energy efficiency are essential to meeting targets.

Where the100% renewable target is adopted, it gives the clearest signal to business that investments in clean technologies will be secure. The report says: “The benefits range from savings on fossil fuel imports, improved energy, and economic security, as well as reduced energy and electricity costs for governments, local residents and businesses.”

There is no case made for nuclear power. Indeed, the report says that the uranium needed for nuclear fuel is − like coal, oil and gas − a finite resource that will soon be running out.

One of the case histories in the report is the Fukushima Prefecture in Japan. In March 2011,  it sustained the world’s worst nuclear accident since the 1986 Chernobyl disaster in Ukraine, and has now opted to go for 100% electricity from renewables by 2040.

Some of the 100% renewable targets detailed in the report are just for electricity production. The authors − Toby Couture, founder of the Berlin-based energy consultancy E3 Analytics, and Anna Leidreiter, climate and energy policy officer at the World Future Council − point out that heating and cooling, and particularly transport, without fossil fuels is far more challenging, but still equally possible. Some countries are already committed to it.

Denmark, a pioneer in the field, has a target of achieving all its electricity and heating needs from renewables by 2035, and all energy sectors − including transport − by 2050. This includes an expansion of wind and solar power, biogas, ground source heat pumps, and wood-based biomass. Because of its investments, the country expects to have saved €920 million on energy costs by 2020.

At the opposite end of the scale, El Hierro, a small island in the Canaries, has a 100% energy strategy, using a wind farm and a volcanic crater. When excess electricity is produced by the wind farm, water is pumped into the volcanic crater, which acts as a storage lake for a hydroelectric plant. This supplements the island’s electricity supply when the wind drops or when demand is very high.

A future component of El Hierro’s strategy is to replace the island’s entire stock of 4,500 cars with electric vehicles, so cutting the need to import fuel.

Surplus electricity

Some places have already exceeded 100% electricity from renewables. The Rhein-Hunsruck district west of Frankfurt, Germany, managed this in 2012, and expects by the end of this year to be producing 230% of its needs, exporting the surplus to neighbouring areas through the national grid. It hopes to use the surplus in future for local transportation, hydrogen or methane production.

There are many other examples in the report, including from San Francisco in the US, Cape Verde island in West Africa, Bangladesh, Costa Rica, and Tuvalu island in the Pacific. These show that both rich and poor communities can share the benefits of the renewable revolution – and, in the case of the 3 billion people still without electric power in the world, bypass the need for fossil fuels altogether.

Jeremy Leggett, a pioneer of solar power and author of a foreword to the report, says: “We are on the verge of a profound and urgently necessary shift in the way we produce and use energy.

“This shift will move the world away from the consumption of fossil resources towards cleaner, renewable forms of power. Renewable energy technologies are blowing the whistle on oil dependency and will spark an economic and social renaissance.

“The question is: Do we make this transition from fossil resources to renewables on our own terms, in ways that maximise the benefits to us today and to future generations, or do we turn our heads away and suffer the economic and social shocks that rising prices and market volatility will create?” – Climate News Network

UN population growth data is bad news for climate

A crowded market in Lagos, Nigeria, Africa's most populous country Image: Zouzou Wizman via Wikimedia Commons
Watch this space: a crowded market in Lagos, Nigeria, Africa’s most populous country
Image: Zouzou Wizman via Wikimedia Commons

By Tim Radford

Sophisticated new analysis indicates an 80% probability that the planet’s population will continue to rise this century, with serious implications for food security, political stability − and climate change.

LONDON, 19 September, 2014 − The demographers may have got it wrong. New projections say the population of the planet will not stabilise at 9 billion sometime this century. In fact, there is an 80% likelihood that, by 2100, it will reach at least 9.6 bn − and maybe rise as high as 12.3 bn.

The latest data, published in the US journal Science, has profound and alarming implications for political stability, food security and, of course, climate change, since greater numbers of people mean greater demands on agricultural land, water and fuel.

At the heart of the findings − led by Patrick Gerland, of the United Nations Population Division in New York, and backed by sociologists, statisticians and population scientists from Seattle, Singapore and Santiago in Chile − is both new data and a more sophisticated approach to the mathematical probabilities for fertility and life expectancy, and for international migration.

Larger families

The new evidence is that, contrary to previous expectations, women in Africa are still having larger families − in part, because contraceptives are not available and because mortality linked to HIV infection has been reduced.

So, by the end of the century, Africa – once relatively sparsely populated, but now home to around one billion people – will have to feed between 3.5 bn and 5.1 bn.

The new information is available because the UN Population Division re-examines its calculations every two years − and the new techniques include the adoption of a methodology known to mathematicians as “Bayesian probabilistic”.

In the new scenarios, Africa remains at the heart of the population explosion, and African women on average have 4.6 children. There are 4.4 bn people in Asia now, but this is expected to peak at 5bn in 2050 and then decline. North America, Europe, Latin America are expected to stay below 1bn each.

“Earlier projections were strictly based on scenarios, so there was no uncertainty,” said Dr Gerland. “This work offers a more statistically-driven assessment that allows us to quantify the predictions and offer a confidence interval that could be useful in planning.”

The study makes no mention of climate change, and the demographers are more concerned with the numbers of young workers who will have to support increasingly elderly populations. But population, economic growth and global warming are inexorably linked.

Most climate change predictions, when they incorporate population growth at all, have been based on the long-standing assumption that the planet’s burden of humans will peak around 2050, and then begin a slow decline.

Because of this, some researchers have been able to put forward arguments for optimism and propose that climate change can be contained and food security assured with careful management and new thinking.

But recent research suggests that while climate change will open more land in higher latitudes for potential crop growth, the gains will not be great, because the conditions for multiple harvests in the tropics will be reduced.

There are other factors. For example, land once available for crops is disappearing under tarmac and cement as the world’s cities grow, and even with a projected population peak of 9bn, an estimated additional 1.5 million square kilometers of tilth and pasture would be lost to the cities by 2030.

Losses of farmland

In addition, the encroachment of the world’s deserts and the erosion of once fertile farmland continues to exact its toll. Statisticians say that between 19 hectares and 23 hectares of land is abandoned every minute. With the latest, and more alarming, population projections, these losses of farmland can only increase.

But these are all projections, rather than predictions. Armed with such information, governments could take steps to ensure a more secure future.

The authors of the Science paper argue that fertility decline could be helped by better access to contraception, and by the education of women.

They add, grimly, that things could also get worse: “It should also be noted that the projections do not take into account potential negative feedback from the environmental consequences of rapid population growth.

“The addition of several billion people in Africa could lead to severe resource shortages, which in turn could affect population size through unexpected mortality, migration, or fertility effects.” – Climate News Network