Tag Archives: Weather

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

Weather patterns show climate is changing US

Streams feeding the Verde River in Arizona may be drying up Image: Jennifer Horn via Wikimedia Commons
Streams feeding the Verde River in Arizona may be drying up
Image: Jennifer Horn via Wikimedia Commons

By Tim Radford

Fiercer tornadoes, more prolonged periods of drought and loss of native fish species are some of the damaging impacts predicted for the US as greenhouse gas emissions continue to rise.

LONDON, 10 September, 2014 − The climate is changing . . . and America’s heartland and southwest are changing with it.

In the southwestern state of Arizona, the streams may be drying up − and that could mean that native fish species will die out.

In the midwest states that citizens call Tornado Alley, the evidence is that there are fewer tornado days per year, but the density and strength of those tornadoes that do form is growing as greenhouse gas emissions continue to rise.

And in the west, which is in the grip of a prolonged drought, things are looking up − but not in a good way. Relieved of the weight of water they normally bear – the 240 billion tonnes of snow and rain that have not fallen since the drought began – the land is starting to rise, with mountains as much as 15 millimetres higher.

More arid

The current drought may not be evidence of climate change – there is a long history of periodic drought in the region – but in general the US southwest is expected to become steadily more arid as planetary temperatures soar.

Kristin Jaeger, assistant professor at Ohio State University’s School of Environment and Natural Resources, reports in the Proceedings of the National Academy of Sciences of the USA that she and colleagues decided to model the surface flow of the Verde River Basin in Arizona by 2050.

Fish that live in these waters are already threatened or endangered, their survival depending on being able to move around the watershed to eat, to spawn and to raise offspring. But the computer simulations for the future suggest that there will be a 17% increase in dried-up streams and a 27% increase in days when there will be no flow of water at all.

What this will do is sever connections between streams, and the deeper pools will become isolated. Native species, such as the speckled dace, the roundtail chub and the Sonora sucker, will increasingly have nowhere to go.

Dr Jaeger calls the estimates conservative. She and her fellow researchers did not take account of the groundwater that will be removed to support the expected 50% increase in human population in Arizona by 2050.

In the US, tornadoes are a fact of life – and death. In 2011, for example, it experienced 1,700 storms during the tornado season, and 550 people died. But scientists have begun to detect a pattern of change. In 1971, there were only 187 days with tornadoes, and in 2013, there were only 79 days, according to James Eisner, a geographer at Florida State University, and colleagues in a report in the journal Climate Dynamics.

But the tornadoes that do form are distinguished by what the scientists call “increasing efficiency”. They are more severe, and there are more of them on a given day.

“We may be less threatened by tornadoes on a day-to-day basis, but when they do come, they come like there’s no tomorrow,” said Professor Eisner.

Meanwhile, Adrian Borsa  and other researchers at Scripps Institution of Oceanography in San Diego report in the journal Science that they have been looking at data from GPS satellite ground stations, to discover that – thanks to the current drought – all of them are on the move.

Highest uplift

Overall, the surface of the arid west has gained 4mm in altitude since the drought began, and the highest uplift, 15mm, has been measured in the mountains.

They put it down to the water that has not fallen and which would normally have covered the mountains as heavy snow. Altogether, the water deficit is 240 gigatonnes, or 62 trillion gallons − the equivalent of a 10cm layer of water across the entire west of the US.

This is roughly the equivalent of the mass of ice lost each year from the Greenland ice sheet.

The crustal movement is not expected to have any impact on the likelihood of earthquakes in, for example, California, but the study could offer researchers a new way of measuring fresh water resources over very large regions.

It could be a case of don’t worry about all those rainfall gauges, just watch how the earth moves. Or, in the researchers technical language, such observations “have the potential to expand dramatically the capabilities of the current hydrological observing network”. – Climate News Network

Less snow won’t end blizzard hazard

Clearing a station platform in Brookly, New York, during the snowstorms in January this year Image: Patrick Cashin/MTA via Wikimedia Commons
Clearing a train station in New York during snowstorms in January this year
Image: Patrick Cashin/MTA via Wikimedia Commons

By Tim Radford

New research predicts that while there will be less snow in a warming world, the sort of severe snowstorms that caused chaos in the US this year will remain a serious hazard.

LONDON, 6 September, 2014 − There’s still a chance that some people who dream of a white Christmas will get their wish. While there may be less snow falling overall in a warming world, there will still be blizzards.

Paul O’Gorman, an atmospheric scientist at the Massachusetts Institute of Technology in the US, reports in Nature that he studied daily snowfall in the northern hemisphere through the prism of 20 different climate models. Each of these projected climate change over a century, according to various emissions of greenhouse gases.

He also looked at seasonal average and extreme snowfall events, both under current conditions and as the planet warms. And the conclusion is that the kind of snowstorms that hit the US in 2014 will remain a hazard, even though there may be fewer of them.

Climate models

“Many studies have looked at average snowfall over a season in climate models, but there’s less known about these very heavy snowfalls,” Dr O’Gorman said. “In some regions, it is possible for average snowfall to decrease but the snowfall extremes actually increase.”

Climate scientists have consistently warned that a rise in average planetary temperatures is likely to be accompanied by a rise in the frequency or intensity of extreme events.

By these, they usually mean windstorms, floods and heat waves. But ice storms remain part of the picture too. That is because even as temperatures on average creep up, there will be places and seasons where the rain could still turn to snow.

The study found that, under high warming scenarios, those low-lying regions with average winter temperatures normally just below freezing would see a 65% reduction in average winter snowfall. But in these places, the heaviest snowstorms on average became only 8% less intense. In the higher latitudes, extreme snowfall became more intense, with 10% more snow, even under scenarios of relatively high average warming.

Heaviest falls

There is a relatively narrow temperature range − just below freezing point − at which the heaviest snowfalls seem to occur.

“People may know the expression, ‘It’s too cold to snow,’” Dr O’Gorman said. “If it’s very cold, there is too little water vapour in the air to support a very heavy snowfall, and if it’s too warm, most of the precipitation will fall as rain.

“Snowfall extremes still occur in the same narrow temperature range with climate change, and so they respond differently to climate change compared to rainfall extremes or average snowfall.” – Climate News Network

Elections sideline São Paulo drought crisis

Drought has now hit dams on rivers such as the Paranapanema Image: José Reynaldo da Fonseca via Wikimedia Commons
Past prime: drought has now hit dams on rivers such as the Paranapanema
Image: José Reynaldo da Fonseca via Wikimedia Commons

By Jan Rocha

As South America’s biggest city suffers its worst drought in over a century, São Paulo state politicians are putting re-election prospects ahead of the need to introduce measures to address a desperate situation for millions of people.

SÃO PAULO, 25 August, 2014 − Outside the semi-arid area of the north-east, Brazilians have never had to worry about conserving water. Year in, year out, the summer has always brought rain.

But that has changed dramatically. São Paulo, the biggest metropolis in South America, with a population of almost 20 million, is now in the grip of its worst drought in more than a century − a water crisis of such proportions that reports on the daily level of the main reservoir arefollowed as closely as the football results.

The lack of rain is also affecting the dams that produce most of Brazil’s energy, highlighting the urgent need to diversify power sources.

And yet the state governor, wary of the effects on his prospects in forthcoming elections, has refused to introduce measures to ration, or even conserve, water.

Mighty rivers

Brazil is blessed not only with the mighty Amazon and all its huge tributaries, but also with dozens of other lengthy, broad rivers − once the highways for trade and slaving expeditions, but now providing waterways for cargo, power for dams, and water for reservoirs.It has at least 12% of the world’s fresh water supply.

But five of the principal rivers – the Tiete, Grande, Piracicaba, Mogi-Guaçu and Paraiba do Sul − that cross or border São Paulo, Brazil’s wealthiest state, have less than 30% of the water they should have at this time of year, according to data from the regional Hydrographic Basin Committee and from the National Electric System Operator (ONS).

Other major water sources – such as the Paraná, South America’s second biggest river, and the Paranapanema − are also suffering from the long dry period. The ruins of towns flooded for dam reservoirs have reappeared, fishermen’s boats are beached because the fish have disappeared, and navigation is at a standstill.

The transport of grain and other cargos to the port of Santos, via the river network, had to be suspended after the water level fell by up to eight metres. The equivalent of 10,000 lorryloads of cargo have been transferred by road so far.

Many industries have suspended their activities because of lack of water, and the drought has resulted in the loss of part of the coffee, sugar cane and wheat crops in one of Brazil’s most important agricultural states.

The hydrological period lasting from October 2013 to March 2014 was the driest for 123 years, according to the Agronomic Institute of Campinas, the oldest institute of its kind in Latin America .

Lowest volume

The federal government’s energy research company, EPE, found that in the first three months of 2014 the volume of rain was the third lowest since the 1930s.

It was the third consecutive year of reduction for the reservoirs of the hydroelectric dams that make up the South-east/Centre-West System, where many of Brazil’s biggest cities are located. From 88% in 2011, the volume of water in them had fallen to 38% by April 2014 – the month in which the dry season begins in this region.

By mid-August, the reservoirs of the Cantareira system, which supplies the water for almost 8.5 million of São Paulo’s inhabitants, had fallen to just 13.5% of capacity.

Yet the state government of São Paulo has so far refused even to admit that there is a crisis. The problem is the October elections, when Governor Geraldo Alkmim is running for re-election. Like most politicians, he does not want to be associated with a crisis. The word “rationing” is taboo.

Instead, unofficial rationing – what might be called rationing by stealth – is in operation. At night, the São Paulo Water Company, Sabesp, is reducing the pressure in the water system by 75%, leaving residents in higher areas of the city with dry taps.

Over 80% of the country’s energy comes from hydroelectric power, and dozens more giant dams are under construction or planned, mostly in the Amazon basin. The government has been strangely reluctant to invest in, or even encourage, other sources of abundant renewable energy, such as wind, solar and biomass.

The over-reliance on hydropower has already led to a distortion. The back-up system of thermo-electric plants, run on gas and diesel, and designed for emergencies, has had to increase production from 8% in 2012 to cover 25% of energy demand this year − thus contributing to higher carbon emissions.

Politics have also interfered with the special crisis committee set up to monitor the drought situation, with representatives from local and federal agencies unable to agree on what to do.

The Sao Paulo energy company, CESP, unilaterally decided this month to reduce the volume of water released from the shared Jaguari reservoir to the neighbouring state of Rio de Janeiro for electricity generation, in order to keep more for its own water needs.

Dangerous precedent

For Marcio Zimmerman, executive secretary of the Ministry of Mines and Energy, CESP’s action creates a dangerous precedent. “There will be chaos if everyone decides to rebel against the ONS,” he said.

The realisation that climate change is already leading to major changes in weather patterns has sounded alarm bells among the business community about the need to diversify energy sources and conserve water.

Early this month, at a seminar organised by the Brazilian Business Council for Sustainable Development, the chief executives of more than 20 top companies drew up a list of 22 crisis-related proposals to be put to the presidential candidates in October’s election.

Newspaper editorials are now urging the politicians to take their heads out of the sand and involve the population in a serious discussion on the crisis and its effects on the water supply, energy generation, and food production .

The Rio newspaper O Globo declared: “They belittle the potential for efficiency available in a society accustomed to waste. When they act, it might be too late.” – Climate News Network

Arctic warming blamed for dangerous heat waves

Feeling the heat: a wildfire rages in New Mexico during the 2012 heat wave in the US Image: Kari Greer/USFS Gila National Forest via Wikimedia Commons
Feeling the heat: a wildfire rages in New Mexico during the 2012 heat wave
Image: Kari Greer/USFS Gila National Forest via Wikimedia Commons

By Paul Brown

Giant waves in the jet stream that often governs our weather are changing as the Arctic warms more rapidly − leading to long periods of soaring temperatures that pose major threats to economies and human health.

LONDON, 16 August, 2014 − Few people have heard of Rossby waves and even less understand them, but if you are sweltering in an uncomfortably long heat wave, then they could be to blame.

New discoveries about what is going on in the atmosphere are helping to explain why heat waves are lasting longer and causing serious damage to humans and the natural world. These events have doubled in frequency this century, and the cause is believed to be the warming of the Arctic.

The weather at the Earth’s surface is often governed by high winds in the atmosphere, known as jet streams. In 1939, Carl-Gustaf Arvid Rossby, a Swedish-born America meteorologist, discovered waves in the northern jet stream that were associated with the high and low pressure systems at ground level that form daily weather patterns.

Jet streams travel at up to 200 kilometres an hour, frequently wandering north and south − with cold Arctic air to the north, and warmer air to the south.

Rapid variations

When the jet stream develops Rossby waves and they swing north, they suck warm air from the tropics to Europe, Russia or the US. And when they swing south, they do the same thing with cold air from the Arctic. The waves constantly change shape, and so cause rapid variations in the weather.

But new research, published in the Proceedings of the National Academy of Sciences of the USA, has discovered a tendency for these waves in the jet stream to get much bigger and to get stuck – particularly in July and August. This causes heat waves that last not just for a few days but for weeks.

This is a serious health and economic threat. A recent example is the record heat wave in the US that hit corn farmers and worsened wildfires in 2012.

Close study of records shows that, from 1980 to 2003, there were two such heat wave events every four years on average. From 2004-07, there were three events, and between 2008-11 there were five.

Ice shrinking

Theory and the new data both suggest a link to processes in the Arctic. Since 2000, the Arctic has been warming about twice as fast as the rest of the globe. One reason for this is that ice is rapidly shrinking in the White Sea − a southern inlet of the Barents Sea on the north-west coast of Russia – and so less sunlight gets reflected back into space, while the open ocean is dark and hence warms more.

“This melting of ice and snow is actually due to our lifestyle of churning out unprecedented amounts of greenhouse gases from fossil fuels,” says Hans Joachim Schellnhuber, co-author of the study and founding director of the Potsdam Institute for Climate Impact Research.

As the Arctic warms more rapidly, the temperature difference to other regions decreases. Yet temperature differences are a major driver of the atmospheric circulation patterns that in turn rule our weather.

“The planetary waves topic illustrates how delicately interlinked components in the Earth system are,” Schellnhuber concludes: “And it shows how disproportionately the system might react to our perturbations.” – Climate News Network

US climate change debate heats up

Skiing areas such as Colorado are being hit by warmer winters Image: DebateLord at Wikimedia Commons
Skiing tourism areas such as Colorado are being hit by warmer winters
Image: DebateLord at Wikimedia Commons

By Kieran Cooke

Groups for and against US government plans for new regulations aimed at cutting greenhouse gas emissions have been slugging it out at a series of heated debates across America.

LONDON, 11 August, 2014 − Achieving progress in cutting back on greenhouse gas emissions and preventing serious global warming is never easy. But just how difficult a task that is became clear at a series of recent meetings across the US held to discuss the Obama administration’s latest plans for tackling climate change.

Those plans, announced in early June by the government’s Environmental Protection Agency, call for substantial nationwide cuts in greenhouse gas emissions.

Power companies − in particular, those operating coal-fired plants − will have to make big adjustments, reducing overall CO2 emissions by 25% on 2005 levels by 2025 and by 30% by 2030.

The EPA-sponsored public meetings, held in four US cities, were packed.

Long overdue

In Denver, in the state of Colorado, representatives of the skiing industry − a vital part of the state’s economy − said the new regulations were long overdue.

Skiing organisations said changes in climate were already happening and the industry was being badly hit, with drier and warmer winters resulting in less and less snow.

But coal mining is also central to Colorado’s economy. One resident of a coal mining community told the meeting: “The environmental extremist war on coal is really a war on prosperity. Coal means families can buy homes and put food on the table.”

The multi-billion dollar US coal industry is training its big guns on the EPA proposals.

Fred Palmer, a representative for Peabody Energy Corporation, the biggest coal producer in the US, told a meeting at the EPA’s HQ in Washington that the government should provide more funds for new technologies such as carbon capture and storage.

“Climate change is an issue we need to deal with in the right way,” Palmer said, “The only way to approach it is with technology, not with command-and-control from Washington.”

Other coal lobbyists have been wading into the fray. The American Coalition for Clean Coal Electricity said the EPA’s emissions cutting programme “threatens to dismantle our nation’s economy, fundamentally alter the American way of life, and severely hamper US energy independence and leadership”.

Groups of campaigners in favour of the EPA proposals demonstrated at the meetings, with the area round the EPA’s Washington office turned into the site of a large green carnival.

Adamantly opposed

Although the Obama administration has a considerable battle on its hands – with many politicians, corporate groups and powerful business organisations adamantly opposed to the new proposals – there are signs that the White House is determined to implement the measures.

Coinciding with the public meetings around the country, the government’s Council of Economic Advisers issued a report saying cutting emissions makes sense economically, as well as environmentally.

For each decade that action on emissions is delayed, costs of meeting reduction targets rise by more than 40%, the report says.

The public mood about the seriousness of climate change and the need to take action seems to back Washington’s stance.

A recent poll carried out by the ABC news network in the US and the Washington Post found that seven out of 10 people think global warming is a serious problem that needs to be tackled – and more than 60% of those questioned wanted action on emissions, even if it means higher energy bills. – Climate News Network

Climate change damages Europe’s forests

Forest fire damage such as this in Portugal is expected to increase Image: Osvaldo Gago via Wikimedia Commons
Forest fire damage such as this in Portugal is expected to increase
Image: Osvaldo Gago via Wikimedia Commons

By Alex Kirby

New research shows that forest ecosystems are particularly vulnerable to rapid changes in the climate – and have been suffering intensified disturbance in Europe for decades.

LONDON, 5 August, 2014 − Climate change is here, it’s happening now, and for the last few decades it has been demonstrably bad news for many of Europe’s forests.

An international team of researchers say in a report from the European Forest Institute that climate change is altering the environment, and it is long-lived ecosystems like forests that are particularly vulnerable to the comparatively rapid changes occurring in the climate system.

The report, published in the journal Nature Climate Change, shows that damage from wind, bark beetles, and wildfires has increased significantly in Europe’s forests in recent years. Windthrow −  the wind’s effect in damaging or uprooting trees − is an increasing problem.

“Disturbances such as windthrow and forest fires are part of the natural dynamics of forest ecosystems, and are not a catastrophe for the ecosystem,”, says the study’s principal researcher, Rupert Seidl, senior scientist at the University of Natural Resources and Life Sciences, Vienna.

Increasing challenges

“However, these disturbances have intensified considerably in recent decades, which increasingly challenges the sustainable management of forest ecosystems.”

The authors show that damage caused by forest disturbance has increased continuously over the last 40 years in Europe, reaching 56 million cubic metres of timber annually in the years from 2002 to 2010.

Analysis of scenarios for the decades ahead suggest this trend will continue, with the study estimating that forest disturbance will increase damage by another million cubic metres of timber every year over the next 20 years.

The study says this increase is roughly equivalent to 7,000 football fields’ worth of timber. The authors say climate change is the main driver behind the increase. Forest disturbance did not increase much beyond present levels in their simulations while climate conditions remained stable.

They estimate that forest fires will cause increased damage on the Iberian peninsula, with damage by bark beetles increasing most markedly in the Alps. Wind damage, they say, is likely to increase most in central and western Europe.

Feedback effect

What the climate does to the forests is not a one-way street, the study says. There is a strong feedback effect from forest disturbances on the climate system.

Europe’s forests are at present helping to mitigate climate change by absorbing large quantities of carbon dioxide. But the carbon lost from the increasing numbers of trees that are damaged or die could reduce this effect and reverse the positive impact of forest management measures aimed at reducing climate change.

So the increase in forest disturbance caused by the climate could simply make climate change worse. Management steps such as increasing biodiversity and thinning the forests to give them better protection can help to reduce these carbon losses and support the forests’ role in mitigating climate change.

But the authors say Europe’s forest managers will need to adapt to changing disturbances in order to keep the forests capable of functioning  to society’s benefit. − Climate News Network

New seeds of hope for Nepal’s farmers

Growing concern: in Nepal, 50% of arable land is planted with rice Image: Sigismund von Dobschütz via Wikimedia Commons
Growing concern: in Nepal, 50% of arable land is planted with rice
Image: Sigismund von Dobschütz via Wikimedia Commons

By Om Astha Rai

Climate-resilient varieties of rice could help to protect crop yields from the ravages of droughts and floods caused by the increasingly erratic weather patterns in South Asia.

KATHMANDU, 30 July, 2014 − Farmers badly affected by changing weather patterns in South Asia now have the opportunity to improve food security by planting new varieties of rice capable of withstanding the impact of both severe droughts and floods.

This is particularly good news for countries such as Nepal, where around 65% of its more than 26 million people are involved in agriculture. Rice is the country’s most important crop, planted on more than 50% of its arable land.

And it comes at a time when new research using satellite imaging has highlighted the growing need to change agricultural practices in South Asia as higher average temperatures cause the reduction of crop yields on the Indo-Gangetic plain.

Scientists say the new seeds, developed by the International Rice Research Institute in the Philippines and approved by the Nepal Agricultural Research Council (NARC), are vital in order to deal with changing weather patterns − in particular, the increasingly erratic behaviour of the all-important South Asia monsoon.

“These new varieties can really change the future of the country’s farmers,” says Dr Dil Bahadur Gurung, NARC’s executive director. “The new rice can, in most cases, beat the effects of droughts and floods.

Reduce impact

“All these varieties have been tested in Nepal’s soil and climate over and over again. If all the country’s farmers replace their traditional varieties with these new ones, the impact of climate change on our agriculture could be reduced considerably.”

Local scientists say the timing of the South Asia monsoon − the only source of irrigation for the majority of Nepali farmers − is changing.

“Each year, we see the monsoon arriving later,” says Mani Ratna Shakya, a leading meteorologist in Nepal. “The duration of the monsoon is also getting shorter as each year passes.”

According to Nepal’s Meteorological Forecasting Division, the monsoon − which usually arrives in Nepal during the first week in June − came 10 days late this year.

Droughts are becoming more frequent. This year, the monsoon is generally judged to be very weak, leaving a vast area of arable land parched, particularly in western parts of Nepal. And often, when the rains eventually do arrive, they are torrential, causing flash floods.

So far, NARC has approved six drought-tolerant varieties of rice, under the name Sukkha − meaning dry.

“Ordinary rice varieties dry out and die in droughts,” says Hari Krishna Uprety, a paddy expert at NARC. “The new seeds survive droughts even in the early stage of growth. And uncertainty about the onset of monsoon has made these varieties even more important.”

Hari Krishna Uprety, NARC paddy expert, with new rice seed varieties Image: Om Astha Rai
Hari Krishna Uprety, NARC paddy expert,
with the new rice seed varieties
Image: Om Astha Rai

The new varieties still need water, of course, but they become more drought tolerant by being able to store energy during the early stages of their growth.

Two rice varieties capable of surviving flood conditions for up to two weeks have also been approved by NARC.

Erratic climate

Although the experts are backing the introduction of the new seeds in order to combat an increasingly erratic climate, persuading farmers to change their cultivation methods is a difficult task.

Farmers are often reluctant to replace traditional rice varieties, which in Nepal tend to be specific to each part of the country, depending on soil conditions, elevation, and other factors.

The new seeds are no more expensive than the traditional ones, and farmers even get a 30% discount on seeds approved by NARC, but a factor that could hamper uptake is that distribution is through the National Seed Company, which is not yet reaching out to farmers in every village.

But scientists warn that the new varieties must be planted – not only to combat changes in climate, but also to feed growing populations. – Climate News Network

• Om Astha Rai is a reporter with Nepalese national newspaper, Republica Daily.

Atlases reveal climate and weather impacts

NASA says Arctic sea ice thickness in some areas has halved since 1980 Image: Hannes Grobe 20:05 via Wikimedia Commons

NASA says Arctic sea ice thickness in some areas has halved since 1980
Image: Hannes Grobe 20:05 via Wikimedia Commons

By Alex Kirby

Two new atlases provide clear visual evidence of the effect climate change and extreme weather can have on people and property.

LONDON, 12 July 2014 – For people who find it hard to believe the Earth really is warming, new visual evidence will soon be available – two atlases, one showing graphically the retreat of Arctic ice, the other the human and economic price exacted by extreme weather.

The 10th edition of the National Geographic Atlas of the World is to be published on 30 September. The publication’s geographer, Juan José Valdés, says the reduction in multi-year ice – ice that has survived for two summers – is so noticeable compared with previous editions that it is the biggest visible change since the breakup of the USSR.

“You hear reports all the time in the media about this,” he said. “Until you have a hard-copy map in your hand, the message doesn’t really hit home.” He believes atlases “open people’s eyes to what’s happening in the world.”

The Arctic sea ice has been retreating in the last 30 years or so by 12% each decade, NASA says. (On land the change is even more marked. Spring and autumn on the Greenland icecap have warmed by more than 3°C, although summer temperatures have not changed)

According to NASA’s Operation IceBridge the sea ice is now as much as 50% thinner than in previous decades, falling from an average thickness of 3.8 metres (12.5 feet) in 1980 to 1.9 m (6.2 ft) in recent years. May 2014 represented the third lowest extent of sea ice for that month in the satellite record, the US National Snow and Ice Data Center (NSIDC) says.

Self-supporting

The ice loss is accelerated by what scientists call a positive feedback: the warming in effect fuels itself. Thin ice reflects light less effectively than thick ice, allowing more sunlight to be absorbed by the ocean, which further weakens the ice and warms the ocean even more.

The melting ice also triggers another feedback. Thinner ice is flatter and scientists say this allows melt ponds to accumulate on the surface, reducing the ice’s reflectiveness and absorbing more heat.

In National Geographic’s atlas the multi-year ice, which is older, is shown as a large white mass, with the maximum extent of sea ice – the pack ice that melts and refreezes each season – shown by a simple line. This edition shows the area of multi-year ice is strikingly smaller than previously.

Some scientists say the atlas should show the total ice area at the end of the Arctic summer, including the remaining ice newly formed in the previous winter. This total minimum cover is measured in September, while total maximum cover is measured in March, at the end of winter.

Omitting the minimum cover means ice one year old or less is not being shown, the critics say. But the mapmakers say they do not show the minimum extent because there is only so much information they can include without confusing users.

There is also criticism of the atlas’s reliance on a single year (the new edition uses 2012 data, an extremely low year for ice cover). The critics say this probably over-emphasises long-term trends. But if 2013, a year with more ice, is shown, the mapmakers counter, it could under-emphasise the trend towards rising temperatures.

Steep underestimate

The second publication, the Atlas of Mortality and Economic Losses from Weather, Climate and Water Extremes 1970-2012, is the work of the World Meteorological Organization (WMO) and the Centre for Research on the Epidemiology of Disasters (CRED) of the Catholic University of Louvain (UCL) in Belgium.

Disasters caused by such extremes, it says, are increasing globally, killing people and slowing economic and social development by years or decades. The period covered, the authors say, saw 8,835 disasters, 1.94 million deaths and US$2.4 trillion of economic losses resulting from droughts, extreme temperatures, floods, tropical cyclones and related health epidemics.

Preparations start in Geneva, Switzerland, on 14 July for the third World Conference on Disaster Risk Reduction, to be held in Japan in March 2015 by the United Nations.

Jochen Luther of WMO told the Climate News Network: “It’s not necessarily the number of extreme events that is increasing, but the increasing exposure and vulnerability that turns them into disasters, as well as better reporting of them than in the past.”

The UN’s Global Assessment Report on Disaster Risk Reduction 2013 said direct and indirect losses from natural hazards of all kinds had been underestimated by at least half because of problems with data collection. – Climate News Network

Climate puts US at risk of multi-billion bill

Overheating: US crops such as cotton face a %20 drop in yield Image: Wars via Wikinmedia Commons
Overheated economy: US crops such as cotton face a 20% drop in yield
Image: Wars via Wikimedia Commons

By Alex Kirby

A study of the possible cost of climate change to the US economy warns government and business that billions of dollars could be at risk through damage to property, reduced harvests and workers incapacitated by extreme heat.

LONDON, 29 June, 2014 − The sheer economic cost of climate change to Americans could be far greater than many realise, an influential study says.

The study was commissioned by the Risky Business Project, a research organisation chaired by a bi-partisan panel and supported by several former US Treasury Secretaries.

It expects climate change to have varied impacts across different regions and industries. Rising sea levels, it says, could destroy many billion dollars’ worth of coastal properties by 2050, and warming temperatures, especially in the south, south-west and mid-west, could cut the productivity of people working outdoors by 3%.

Without a change in crops, harvests in these regions could fall by 14%. But further north, in states such as North Dakota and Montana, winter temperatures will probably rise, reducing frost and cold-related deaths and lengthening the growing season for some crops.

Kate Gordon, executive director of the Risky Business Project, said : “We still live in a single integrated national economy, so just because it’s not hot where you are doesn’t mean you won’t feel the heat of climate change.”

Michael Bloomberg, a former mayor of New York, said: “Damages from storms, flooding, and heat waves are already costing local economies billions of dollars. We saw that firsthand in New York City with Hurricane Sandy.

Costs of inaction

“With the oceans rising and the climate changing, the Risky Business report details the costs of inaction in ways that are easy to understand in dollars and cents − and impossible to ignore.”

Hank Paulson, a former Treasury Secretary and co-chair of the Risky Business Project, said the report shows us that “our economy is vulnerable to an overwhelming number of risks from climate change.

“But if we act immediately, we can still avoid most of the worst impacts of climate change and significantly reduce the odds of catastrophic outcomes. But the investments we’re making today will determine our economic future.”

In a section on short-term climate threats, the authors say: “The American economy is already beginning to feel the effects of climate change. These impacts will likely grow materially over the next 5 to 25 years…”

“Just because it’s not hot where you are doesn’t mean
you won’t feel the heat of climate change”

They say there is a 1-in-20 chance of yield losses of more than 20% in corn, wheat, soya and cotton crops over that timespan.

On energy, they say changes in temperature driven by greenhouse gases will probably mean a need to build roughly 200 average coal-fired or natural gas-fired power plants between 2020 and 2045, costing up to $12 billion per year.

Climate impacts, the report says, are unusual because future risks are directly tied to present decisions. By failing to lower greenhouse gas emissions today, decision-makers put in place processes that increase overall risks tomorrow.

By 2050, on present trends, $66bn-$106bn worth of existing coastal property will probably be below sea level nationwide, with $238-$507bn worth by 2100.

By mid-century, the average American will probably see 27 to 50 days over 95°F (35°C) each year − two to more than three times the average annual number of such days seen over the last 30 years. By the end of the century, this number will probably average 45 to 96 days over 95°F each year.

But the study says that the south-west, south-east, and upper mid-west will probably see several months of 95°F days annually.

Human threshold

In the longer term, extreme heat during parts of the year could pass the threshold at which the human body can no longer maintain a normal core temperature without air conditioning. At these times, anyone who has to work outdoors, or without access to air conditioning, will face severe health risks and possible death.

The authors say they hope it will become standard practice for the American business and investment community to factor climate change into its decision-making process. They say: “We are already seeing this response from the agricultural and national security sectors; we are starting to see it from the bond markets and utilities as well.

“But business still tends to respond only to the extent that these risks intersect with core short-term financial and planning decisions.”

And the authors warn the government: “We also know that the private sector does not operate in a vacuum, and that the economy runs most smoothly when government sets a consistent policy and a regulatory framework within which business has the freedom to operate.

“Right now, cities and businesses are scrambling to adapt to a changing climate without sufficient federal government support…” − Climate News Network