Best of our wild blogs: 18 Apr 13

Celebrate Earth Day on our wild shores this Saturday!
from wild shores of singapore

Paint along with Pui San
from Art in Wetlands

Telling these two apart
from Life's Indulgences

Random Gallery - Colour Sergeant
from Butterflies of Singapore

NEA Organises First-Ever Government-Led Hackathon [Press Releases] from Green Business Times

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Pulau Ubin and the unsettled Singapore psyche

Terence Chong and Yeo Kang Shua Today Online 18 Apr 13;

The public unhappiness over fears that Pulau Ubin was to be developed has two abiding messages for us. The first is that pockets of rural spaces are close to sacred for many Singaporeans.

Pulau Ubin is more than an underdeveloped island off the mainland. It is also a crucial space that offers psychological distance from the metropolis, allowing visitors to bathe in nostalgia and imagine themselves as more than mere city-dwellers, if only for a few precious hours.

The second is that the fortunes of Pulau Ubin, like many other spaces in Singapore, are in bureaucratic limbo. The fate of the island is held in suspension, contingent on the country’s housing needs, and this uncertainty has a long-term profound impact on Singaporeans’ sense of belonging and psyche.

The lesson here is not that spaces must be sacrificed for the country’s housing needs but that spaces, regardless of natural or heritage worth, are transient in Singapore and it is better not to get too attached to them.

FROM 1958 TO 2002

Indeed, the uncertainty of Pulau Ubin’s fate has been reflected in official documents through the decades.

The 1958 Master Plan designated the island as “Mineral Workings” and “Fisheries Reserves”. The 1977 and 1980 Master Plans labelled the island “Rural” and “Unplanned”, respectively. And from the revised 1985 Master Plan to the present 2008 one, Pulau Ubin is seen as an “Open Space, Sports and Recreation, Agriculture, Reserve Site”.

Hints of development grew clearer in the 1991 Concept Plan. It stated that “Pulau Tekong and Pulau Ubin will be safeguarded for leisure and recreation purposes for as long as possible. However, if the population exceeds four million, they will be developed by Year X — linked to the mainland by the MRT and a major road.”

The current 2001 Concept Plan removed mention of development but expressed plans to keep Pulau Ubin, Lim Chu Kang and other existing nature areas in their rustic state for as long as possible. A road link from the mainland to the island is still on the cards. The same position was reiterated in the Parks and Waterbodies Plan and Identity Plan 2002.

This uncertainty also played out in the Chek Jawa saga. In 2001, news of impeding reclamation works on the eastern shores of Pulau Ubin provoked outcry from nature enthusiasts. At stake was the rich biodiversity of marine life. On Jan 14, 2002, the Ministry of National Development (MND) announced the decision to put off reclamation work for as long as the island was not required for development.

Interestingly, the 2001 reclamation announcement coincided with the 2001 Concept Plan which, as mentioned above, had already announced the state’s decision to keep the island in its rustic state for as long as possible. Today Chek Jawa remains just as vulnerable to development as there is no legal protection for the site, unlike the Sungei Buloh Wetland Reserve.


Nothing is as unsettling as an open-ended existence.

In the minds of many, our reluctance to save such spaces goes against the grain of the official narrative. If we are, as we are often reminded, a country lacking in natural resources, why then are we so hesitant when it comes to protecting whatever little we have?

This dissonance between rhetoric and practice may not have been noticed during our developing years when economic well-being was the national priority. However, with a more mature and better-informed population, it will become louder and, given the current concerns of overcrowding, political.

Heritage is now part of the political conversation and new ways to enrich this conversation have to be explored.

Would the gesture of gazetting a part of the island — or even a small portion of Bukit Brown for that matter, say, the hill on which rests the Ong Sam Leong grave, the biggest in the cemetery — derail the nation’s housing plans? Or would it send the signal that heritage and national identity are worth sacrificing for?

Such a gesture would not only bring state-civil society relations to a new level but, more importantly, offer a much needed sense of permanence and durability to our national identity.


The truth is nation-building is an inherently political project. One cannot expect citizens to sink roots into the land or be called to defend it without expecting them to be angry, even confrontational, when spaces like Pulau Ubin and Bukit Brown are vulnerable.

It is thus important for civil servants and civil society activists alike to understand that the bridges of communication must always be kept open in order for dialogue to take place. Without this dialogue, both parties will become more entrenched in their positions and less willing to compromise.

On one hand, civil servants have to break the habit of evoking “national interest” to counter heritage arguments. The state does not have a monopoly over the definition of “nation” and civil society groups, after all, have national interests at heart too. Furthermore, it may be counter-intuitive to some that destruction of heritage and natural land can be for the good of the nation.

On the other, civil society has to persistently reach out to civil servants and government agencies, offering their expertise and ground knowledge in order to produce better-informed policies. Civil society groups must find the stamina to continually seek out agreeable government representatives who are willing to engage them sincerely.


Looking ahead, the question over Pulau Ubin is about striking a balance between withholding development and preservation — for they are not the same thing.

The Government’s recent announcement that it plans to keep Pulau Ubin in its current state for the foreseeable future is the withholding of development. This alone is not enough.

The Parks and Waterbodies and Rustic Coast Subject Group Report of the Parks and Waterbodies Plan and Identity Plan 2002 succinctly observed that inactivity will not preserve but, instead, lead to the further deterioration of the social and natural environment. This is because preservation is difficult when there is no community.

Hence, a balance must be struck. This takes considerable long-term thinking, planning and control over what happens to Pulau Ubin. With political will and civil society initiative, there is no reason why this cannot be done.


Terence Chong and Yeo Kang Shua are executive committee members of the Singapore Heritage Society.

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Overseas Family School in limbo over Pasir Ris site

Tan Weizhen Today Online 18 Apr 13;

SINGAPORE — The protracted discussions between the Government and a group of residents seeking to preserve a 5-hectare woodland in Pasir Ris have put one of the biggest international schools here in a pickle.

The Overseas Family School has to move out of its existing premises on Paterson Road by 2015 because of construction of the Thomson MRT Line.

TODAY understands that the school had put in a proposal for the 4-ha Pasir Ris site under the Economic Development Board’s (EDB) request-for-interest exercise which ended in July last year.

However, to date, the Government has not granted approval, with the Ministry of National Development (MND) and some its agencies engaging the Pasir Ris residents over the last nine months. The residents had started a petition to save the forested patch of land which is home to several endangered bird species. The woodland is the size of two football fields and is flanked by Pasir Ris Drive 3, Elias Road and Pasir Ris Heights.

The authorities had previously told the residents that the site was earmarked for an unnamed international school but they did not provide more details, such as whether it would be a new school or an existing one that had to be relocated.

Property analysts said the Overseas Family School would be racing against time to build a new school by 2015. They noted that it would take about two to three years to develop a plot of land and build a school, and there are limited alternative sites that can permanently house the school’s 3,750 students.

The school said as much in January in its Initial Public Offering (IPO) prospectus. The money raised from the IPO was to be used for building a new campus.

In the prospectus, the school warned investors that in the event that it is “not able to complete the construction of our new school campus before the expiry of the lease extension” of its existing site on June 30, 2015, it may be required to secure “alternative temporary premises”. It added that such a scenario “may also result in a decline in student enrolment”.

When contacted, the Overseas Family School declined comment. Responding to TODAY’s queries, an MND spokesman would only say the proposal for school use at the Pasir Ris plot is “currently being assessed and details will be made known once ready”.

An EDB spokesman said in the meantime, the agency “will continue to work with international schools to ensure there are sufficient high quality international school places available”. He added: “This is important to support the investments of global companies to grow in and from Singapore.”

TODAY understands that three sites, in Pasir Ris, Depot Road area and Punggol, were put up during the EDB’s request-for-interest exercise. However, the sites at Depot Road and Punggol are not large enough to accommodate the Overseas Family School.

The property analysts said that one option is to temporarily house the Overseas Family School in old primary or secondary school buildings, which typically can hold not more than 1,000 students each. This means that the international school might have to reduce enrolment or house its students at different locations.

Mr Colin Tan, Head of Research and Consultancy at Chesterton Suntec International, noted the designs for schools have to be “more customised” and there is “less scope for pre-fabrication which would have saved time”. “There are also few other vacant sites which are suitable — traffic conditions must be right to accommodate 4,000 students, for instance,” he said.

Mr Nicholas Mak, Executive Director at SLP International Property Consultants, said the Government is in an unenviable position.

Nevertheless, he noted that it was “a little unusual for the Government to put off the development of a land parcel if there is a real need for a new development”. While he felt the Government should consult the parties involved, he questioned if a precedent would be set if the authorities put off development of the Pasir Ris woodland.

He said: “If word gets out that the authorities will delay (the development of a plot of land) just because of some special interest groups, where does this leave us?”

Ms Cherry Fong, a representative of the Pasir Ris Greenbelt Committee set up by residents to preserve the woodland, said the group has “consistently maintained a sensible rationale” for the preservation of the area.

Adding that they have made clear their position on the adverse impact of the destruction of the woodland, she said: “We have also made it categorically clear that there are no justiciable grounds for the authorities to clear the Pasir Ris greenbelt at all for whatever reason, whether it is to build an international school or for that matter any other urban development like private condominiums, which are sheer commercial profit-driven enterprises.”

MND: Site currently zoned as ‘residential’
Tan Weizhen Today Online 18 Apr 13;

In an email last month to the Pasir Ris residents seeking to save the woodland, the Ministry of National Development (MND) said that the forested area is “not sufficiently unique” to be recommended to be preserved as a park or nature reserve. Nevertheless, there are “no plans to clear” the plot of land until the site is rezoned and awarded to a developer, it said.

The MND said that following feedback from the residents, a second — and more detailed — environment survey was conducted and the National Parks Board assessed that the existing nature reserves “generally contain about three or four times the bird diversity, and seven to 10 times the plant diversity as compared to the subject site in Pasir Ris”. It said: “Secondary forests are already represented as an ecosystem within the existing Nature Reserves.”

The contents of the email was put up on the Facebook page of the Pasir Ris Greenbelt Committee, which was formed by a group of Pasir Ris residents seeking to preserve the forested area.

The MND said that the site is currently zoned as “residential” for development. It added: “It will need to be rezoned to ‘Educational Institution’ before a school can be approved at this location. Residents will have an opportunity to express their views to the Minister for National Development on any proposed rezoning for the site, and a panel of persons will be appointed to hear the representation.”

In its response, which was also put up on the Facebook page, the committee claimed that in November last year, representatives from the MND and the Urban Redevelopment Authority had informed the residents that it was confirmed that the international school would be set up in the area but the authorities were unable to release the name or any other details yet. The residents were also given the impression that the MND “is already in discussion with the international school”, the committee claimed.

It also criticised the authorities’ “lack of sincerity” in engaging with the residents and described the invitation to air their views as “nothing short of a formality”.

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Pre-dawn storms hit commuters hard

Many end up late for work; more showers likely over next two weeks
Jermyn Chow And Christopher Tan Straits Times 18 Apr 13;

PRE-DAWN thunderstorms and gusty winds rattled most parts of Singapore yesterday, disrupting traffic and causing a morning peak-hour crush on the rail network.

There were reports of flash floods in parts of the island, fallen trees and traffic snarls on all major roads and expressways.

The violent thunderstorm, known as a Sumatra squall, which lasted about six hours, uprooted 15 trees and snapped the branches of 25 others, said the National Parks Board.

The heavy rain eased only after 8am. At least one car was damaged.

All fallen trees were cleared within an hour of being reported, said Mr Oh Cheow Sheng, National Parks Board Streetscape Director. Affected areas included Geylang, Tampines, Mount Faber, Whampoa and Holland, he added.

The weather woes also clogged up most expressways and major roads. Commuter alerts on the Land Transport Authority's Twitter account reported at least 15 accidents.

The rain and the usual morning rush hour contributed to another crush on the MRT network.

At Jurong East interchange, overcrowding on the platform was so bad that marshals stood by as helpless as commuters. The noise drowned out station announcements, leading to some confusion among those waiting.

Bukit Gombak resident and equity broker Manoj Kumar, 42, said: "It's so confusing and frustrating. The trains are coming, but at very long intervals."

He said he had to wait for some 15 minutes - instead of the usual three minutes - before getting onto a train, only to have it stop several times on the track.

"From Jurong to Clementi, it stopped three times on the track," Mr Kumar said.

When contacted, an SMRT spokesman said the hold-up was caused by the usual morning congestion as well as the rain. Because of the latter, the tracks were wet, and train drivers had to go slower as the lower friction could lead to longer braking distances.

Hit by the delays on the roads and trains, thousands of commuters showed up for work late.

Among them was accountant Tricia Lee, who made it to her workplace in Raffles Place by train, arriving nearly an hour late.

Said the 28-year-old who lives in Khatib: "I've not encountered such crowds in a very long time... the trains were so packed and bodies were pressing against each other.

"I should have worked from home."

Sumatra squalls are eastward-moving lines of thunderstorms that whip up strong, gusty winds and heavy rain.

They can develop at any time of the year and happen regularly between April and October.

April is likely to be wet, with above-average rainfall expected. This time of the year is usually the transitional period between the north-east and south-west monsoons.

For the next fortnight, Singapore is expected to have mostly short, thundery showers in the afternoon on five to six days.

Widespread showers with gusty winds are likely in the pre-dawn hours and mornings on one to two days.

Bank officer Jean Lai, 28, who takes a train from Bishan to Orchard, said she might leave her house 15 minutes earlier just so she can make it to work in time.

"Even if trains are going to move slower or are delayed, I still have some buffer and hopefully I can avoid the crowds too."

Related post
Stormy shores: The Sumatras on the wild shores of singapore blog.

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Demand for lion bones offers South African breeders a lucrative return

Fears of a rise in poaching as Asian traders look for alternatives to tigers as a source of ingredients for traditional medicine
S├ębastien Hervieu Guardian Weekly 16 Apr 13;

Koos Hermanus would rather not give names to the lions he breeds. So here, behind a 2.4-metre high electric fence, is 1R, a three-and-a-half-year-old male, who consumes 5kg of meat a day and weighs almost 200kg. It will only leave its enclosure once it has been "booked"' by a hunter, most of whom are from the United States. At that point the big cat will be set loose in the wild for the first time in its life, 96 hours before the hunt begins. It usually takes about four days to track down the prey, with the trophy hunter following its trail on foot, accompanied by big-game professionals including Hermanus. He currently has 14 lions at his property near Groot Marico, about two and a half hours by road west of Johannesburg.

After the kill Hermanus will be paid $10,000, but he can boost his earnings further by selling the lion's bones to a Chinese dealer based in Durban. At $165 a kilo (an average figure obtained from several sources) the breeder will pocket something in the region of $5,000.

If his client does not want to keep the lion's head as a trophy, the skull will fetch another $1,100. "If you put your money in the bank you get 8% interest," he explains, "but at present lions show a 30% return."

According to several specialists the new market is soaring. "In the past three months we have issued as many export licences as in a whole year," says an official in Free State, home to most of South Africa's 200 lion breeders. In 2012 more than 600 lions were killed by trophy hunters. The most recent official figures date from 2009, certifying export of 92 carcasses to Laos and Vietnam. At about that time breeders started digging up the lion bones they had buried here and there, for lack of an outlet.

Asian traders started taking an interest in South African lions in 2008, when the decline in tiger numbers – now in danger of extinction – became acute. In traditional Chinese medicine, tiger wine, made using powdered bones, allegedly cures many ills including ulcers, cramp, rheumatism, stomach ache and malaria. The beverage is also claimed to have tonic qualities, boosting virility.

Despite the lack of scientific proof this potion is very popular, so with tiger bones increasingly scarce, vendors are replacing them with the remains of lions. Traders soon realised that South Africa could be a promising source. It is home to 4,000 to 5,000 captive lions, with a further 2,000 roaming freely in protected reserves such as the Kruger national park. Furthermore such trade is perfectly legal.

But a South African investigator, who has been working in this field for 35 years, paints a murky picture. "The legal market only accounts for about half the business, the other half depends on fraud and poaching, which make it possible to obtain bigger volumes, more quickly, and without attracting attention," he asserts, adding: "It's exactly the same people buying lion bones and poaching rhino horns. It's all connected." Sentenced to 40 years in prison last November for fraudulently obtaining and exporting rhino horns, the Thai trafficker Chumlong Lemtongthai also purchased lion bones on his trips to South Africa. "At the end of last year, at Johannesburg international airport, we intercepted several lion bones among bits of rhino horn and ivory, all in a packet ready for despatch," says Hugo Taljaard, head of the Revenue Service's detector dog units. In six months' time South Africa will have 16 dogs trained to detect the smell of lion bones, compared with only two at present.

In June 2012 an online petition calling on President Jacob Zuma to ban the export of lion bones and body parts attracted 750,000 signatures. "The fact that the business is legal just fuels demand, but with the supply-side unable to keep up, buyers will increasingly switch to lions that are still in the wild, including elsewhere in Africa, despite them being endangered," warns Pieter Kat at the NGO LionAid. "To prevent that risk, it would be better to let us cater for growing demand," counters Pieter Potgieter, head of the South African Predator Breeders Association.

"As the price of bones is rising steadily, some breeders have started slaughtering their own lions, without obtaining a permit or getting a vet to put the animal to sleep," says a fraud inspector. "But with the present wave of rhino poaching, we've neither the time nor the resources to address the problem."

• This story appeared in Guardian Weekly, which incorporates material from Le Monde

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Explainer: what is hydroelectricity?

Vladimir Strezov, Macquarie University Science Alert 18 Apr 13;

Hydroelectricity is an established power-generation technology with over 100 years of commercial operation. Hydroelectricity is produced when moving water rotates a turbine shaft; this movement is converted to electricity with an electrical generator.

According to Euromonitor, hydroelectricity made up 17% of the total world electricity production in 2012. The top four largest electricity producing power stations in the world are all hydroelectric: the Three Gorges in China (18.5 GW), Itaipu in Brazil (14.8 GW), Guri in Venezuela (10.1 GW) and Tucuri in Brazil (8.4 GW).

Australia has more than 100 hydroelectric power stations, with the majority located in New South Wales and Tasmania. The annual production of hydroelectricity in Australia for 2012 was slightly over 6% of the total annual power generation, contributing only 0.4% of the world’s total hydroelectricity production.

The largest hydropower station in Australia is Snowy Mountains Hydroelectric Scheme with a capacity of 3.8 GW, representing almost half of the total hydropower capacity in Australia.
Hydropower technologies

There are three main categories of hydropower technologies: run of river, impoundment, and pumped storage.

The run-of-river technology relies on the flow of the river at an elevated point, which, through gravity, is fed to a turbine generator.

Impoundment hydropower systems employ one or more dams to store water. The potential energy stored in the dam is converted to electricity by passing the stored water from an elevated point through a turbine generator located at the lower point.

Pumped hydropower is a two-dam system, where one dam is installed at a higher point to the other. During off-peak hours when the cost of electricity is low, the water from the lower reservoir is pumped up to the elevated reservoir using electricity from the grid. When the cost of electricity is high during peak hours, the water is released from the upper dam to generate electricity. Pumped hydropower is the only hydropower system that produces a non-renewable form of hydroelectricity.

Hydroelectric limitations

Most of the installed hydropower stations around the world and in Australia are impoundment-based, utilising large reservoirs for storage of water. The electricity generated from these systems is renewable, but is not greenhouse gas neutral.

The hydropower dams are a source of methane, which is 25 times more greenhouse potent than carbon dioxide (CO2).

Methane is formed in the dam when organic matter decays in the absence of oxygen. The organic matter is made up of both the plant material flooded when the dam is initially filled, and plant and soil debris washed into the dam from the banks and upstream. Phytoplankton is also a source of dam emissions in the form of organic matter.

Dams with large seasonal differences in height will produce methane emissions from a continual cycle of growth and decay on the banks when plants grow in summer, only to be flooded again in winter.

Another disadvantage of the hydropower technology is the large areas of land needed to construct large hydropower dams.

It is common for very large hydroelectric facilities to have dams measuring several thousand square kilometers. This poses many environmental and social challenges such as altered ecosystems, the loss of archaeologically and culturally significant sites, and displacement of whole communities. As an example, construction of the Three Gorges Dam in China required the relocation of over 1 million people.

The large surface areas of hydro dams also increase water loss through evaporation. At an average, loss of water from hydroelectric dams is in the range of around 35kg/kWh. This is significant for a dry continent like Australia.
Still a role to play

Despite these limitations, hydropower is the only mature renewable electricity generation technology that is flexible to provide both peak and base load electricity requirements at a cost comparable to coal-produced electricity.

The future of hydroelectricity relies on careful planning to minimise negative impacts to communities, ecosystems and culturally significant sites.

The run-of-river technology is the most environmentally benign method of hydroelectricity production and a greater share of this technology should be given in future energy generation.

The future of the pumped-storage hydropower stations relies on use of intermittent wind and solar energy sources, instead of grid electricity, to pump water between reservoirs.

Decreasing Australia’s close-to-90% coal dependence for electricity generation should be the ultimate goal for future energy technology developments and hydropower still has a role to play.

Vladimir Strezov does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.

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British children 'deeply concerned' about the impact of climate change

Survey reveals 11 to 16-year-olds are worried about how global waming will affect them, as well as children in poorer nations
Damian Carrington 17 Apr 13;

British children are deeply concerned about the impact of climate change on their own lives and those of children on poorer nations, according to a new poll for Unicef.

Three-quarters of 11 to 16-year-olds were worried about how global warming will change the world and wanted the government to do more to tackle the threat. But the results come as the row increased over the dropping of debate over climate change from the national curriculum for under-14s' geography classes, with the delivery of a 65,000-strong petition to the Department for Education.

The Unicef poll, conducted by Ipsos-Mori, found that two-thirds of young people were worried about how climate change will affect other children and families in developing countries and that only 1% said they knew nothing about climate change.

"The results of this survey offer a timely reminder to politicians that climate change is an issue of tremendous concern to Britons and casts a long shadow over young people's view of their future," said David Bull, Unicef UK's executive director. "Young people are not only concerned about their own future [but also] the impact climate change is having on children in less developed countries where climate change is a key driver of hunger and malnutrition."

Bull urged the energy and climate change secretary, Ed Davey, attending a conference in Ireland on hunger and climate justice, to commit the UK's fair share to international funds to help children adapt to the effects of climate change.

The petitions protesting the proposed changes to the school curriculum were delivered to Michael Gove's department by 15-year-old student Esha Marwaha from Hounslow and geography teacher Margaret Hunter from Oxfordshire.

Marwaha said: "People are angered by Gove's decision to remove references to climate change. Teaching only a selective part of a vital topic has ramifications for the future. It's not about forcing students to believe in climate change, it's about allowing them to make an informed decision based on what they learn."

Almost 100 leading environmental figures, including the broadcaster Sir David Attenborough, also intervened this week. "Education on the environment would start three years later than at present and all existing references to care and protection would be removed," the letter to the Sunday Times states. "This is both unfathomable and unacceptable. Today's children are tomorrow's custodians of nature."

The Guardian revealed in March that draft guidelines for children in key stages 1-3 had removed discussion of climate change in the geography syllabus, with only a single reference to how carbon dioxide produced by humans affects the climate in the chemistry section. All references to sustainable development have also been dropped in a move widely interpreted as the result of political interference.

Critics say one of the dangers of waiting until GCSE courses to teach about climate change in any depth is that only a minority of pupils study geography at that level. The government's former science adviser, Prof Sir David King, denounced the government proposals as "major political interference with the geography syllabus".

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Climate scientists struggle to explain warming slowdown

Alister Doyle PlanetArk 17 Apr 13;

Scientists are struggling to explain a slowdown in climate change that has exposed gaps in their understanding and defies a rise in global greenhouse gas emissions.

Often focused on century-long trends, most climate models failed to predict that the temperature rise would slow, starting around 2000. Scientists are now intent on figuring out the causes and determining whether the respite will be brief or a more lasting phenomenon.

Getting this right is essential for the short and long-term planning of governments and businesses ranging from energy to construction, from agriculture to insurance. Many scientists say they expect a revival of warming in coming years.

Theories for the pause include that deep oceans have taken up more heat with the result that the surface is cooler than expected, that industrial pollution in Asia or clouds are blocking the sun, or that greenhouse gases trap less heat than previously believed.

The change may be a result of an observed decline in heat-trapping water vapor in the high atmosphere, for unknown reasons. It could be a combination of factors or some as yet unknown natural variations, scientists say.

Weak economic growth and the pause in warming is undermining governments' willingness to make a rapid billion-dollar shift from fossil fuels. Almost 200 governments have agreed to work out a plan by the end of 2015 to combat global warming.

"The climate system is not quite so simple as people thought," said Bjorn Lomborg, a Danish statistician and author of "The Skeptical Environmentalist" who estimates that moderate warming will be beneficial for crop growth and human health.

Some experts say their trust in climate science has declined because of the many uncertainties. The UN's Intergovernmental Panel on Climate Change (IPCC) had to correct a 2007 report that exaggerated the pace of melt of the Himalayan glaciers and wrongly said they could all vanish by 2035.

"My own confidence in the data has gone down in the past five years," said Richard Tol, an expert in climate change and professor of economics at the University of Sussex in England.

Swedish chemist Svante Arrhenius first showed in the 1890s how man-made carbon dioxide, from coal for instance, traps heat in the atmosphere. Many of the exact effects are still unknown.

Greenhouse gas emissions have hit repeated record highs with annual growth of about 3 percent in most of the decade to 2010, partly powered by rises in China and India. World emissions were 75 percent higher in 2010 than in 1970, UN data show.


A rapid rise in global temperatures in the 1980s and 1990s - when clean air laws in developed nations cut pollution and made sunshine stronger at the earth's surface - made for a compelling argument that human emissions were to blame.

The IPCC will seek to explain the current pause in a report to be released in three parts from late 2013 as the main scientific roadmap for governments in shifting from fossil fuels towards renewable energies such as solar or wind power, the panel's chairman Rajendra Pachauri said.

According to Pachauri, temperature records since 1850 "show there are fluctuations. They are 10, 15 years in duration. But the trend is unmistakable."

The IPCC has consistently said that fluctuations in the weather, perhaps caused by variations in sunspots or a La Nina cooling of the Pacific, can mask any warming trend and the panel has never predicted a year-by-year rise in temperatures.

Experts say short-term climate forecasts are vital to help governments, insurers and energy companies to plan.

Governments will find little point in reinforcing road bridges over rivers, for instance, if a prediction of more floods by 2100 doesn't apply to the 2020s.

A section of a draft IPCC report, looking at short-term trends, says temperatures are likely to be 0.4 to 1.0 degree Celsius (0.7-1.8F) warmer from 2016-35 than in the two decades to 2005. Rain and snow may increase in areas that already have high precipitation and decline in areas with scarcity, it says.


Pachauri said climate change can have counter-intuitive effects, like more snowfall in winter that some people find hard to accept as side-effects of a warming trend. An IPCC report last year said warmer air can absorb more moisture, leading to heavier snowfall in some areas.

A study by Dutch experts this month sought to explain why there is now more sea ice in winter. It concluded melted ice from Antarctica was refreezing on the ocean surface - this fresh water freezes more easily than dense salt water.

Some experts challenged the findings.

"The hypothesis is plausible I just don't believe the study proves it to be true," said Paul Holland, an ice expert at the British Antarctic Survey.

Concern about climate change is rising in some nations, however, opinion polls show. Extreme events, such as Superstorm Sandy that hit the U.S. east coast last year, may be the cause. A record heatwave in Australia this summer forced weather forecasters to add a new dark magenta color to the map for temperatures up to 54 degrees Celsius (129F).

(Reporting By Alister Doyle, extra reporting by Gerard Wynn in London; editing by Janet McBride)

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