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March, 2013:

Air travel is an environmental sore spot

Air travel is an environmental sore spot


Special to The Globe and Mail

PublishedThursday, Mar. 21 2013, 7:00 AM EDT

Covering a global industry like automotive is air travel dependent.

I won’t go into the awful details, but my annual carbon footprint is alarming. British Airways estimates in-flight carbon dioxide emission of a 10th of a kilogram per passenger, per kilometre. It’s more for short-haul flights. A 7-1/2 hour overseas flight means a passenger like yours truly can be responsible for kicking out about 700 kilograms of CO2 going one way.

The Green Highway

GM’s new diesel Cruze won’t impress enthusiasts

Aviation has been growing faster than any other source of greenhouse gases and flying now accounts for about 2 per cent of global greenhouse gas emissions, more in developed countries. The aviation industry wants to stop growth of carbon emissions by 2020 and hopes to achieve a 50 per cent decrease in carbon emissions only by 2050.

Jet fuels are kerosene-based and, given the energy density of kerosene, there really is no commercial alternative to the stuff at the moment. However, the U.S. military and a number of airline companies and airliner manufacturers have invested heavily in jet fuel made from plants – the oils provided by weedy camelina or jatropha shrubs or even algae.

A number of these biofuels have successfully passed trials over recent years. None of the tests I have seen involve mixing any more than 50 per cent biofuel into the regular kerosene-based stuff; also these biofuels are more expensive and not available in enough quantity or in enough places to be counted on by airlines. However, I have noticed two recent developments that suggest progress.

British Airways just signed a deal to purchase waste-to-biojet fuel produced by GreenSky from a facility under development in East London by U.S.-based Solena Fuels Corp. According to the purchase agreement, British Airways will buy fuel produced at the plant for the next 10 years, worth approximately $500-million. British Airways, like most of the industry, has a goal to reduce its net carbon emissions 50 per cent by 2050.

More than 150 jobs will be created to operate the facility, as well as an estimated 1,000 during construction. The partners aim to have the plant operational by 2015. Robert Do, president of Solena, said the agreement represents the largest advanced biofuel commitment ever made by an airline.

Another announcement last week came from KLM. A new KLM Royal Dutch Airlines route between Amsterdam and New York’s JFK will be the first to use RSB-certified fuel. RSB means Roundtable on Sustainable Biofuels and it certified that the jet fuel produced will meet environmental and social safeguards.

The fuel is supplied by SkyNRG, the first worldwide biofuel operator to achieve the RSB certification for its entire supply chain. The company only uses sustainable feedstock for conversion into biofuel, and ensures that protected areas and wildlife habitats are unaffected by the growth of feedstock. This is then processed and refined into Jet A1 fuel for use in aircraft.

The climate-friendly value of these biofuels depends largely on how they are produced. It turns out that fuel made from palm oil is worse for greenhouse gas levels in the atmosphere than jet fuel refined from petroleum because it involves clearing rainforest or peatland.

The short-term impact of biofuels for aviation is rather limited. The International Air Transport Association (IATA) thinks a 6 per cent share of sustainable second-generation biofuels is achievable by 2020. Boeing supports a target of 1 per cent of global aviation fuels by 2015. This all supports the industry’s goal of stopping growth of carbon emissions by 2020 and achieving a 50 per cent decrease in carbon emissions by 2050.

A better idea might be to have people like me travel less. It’s the growth of aviation that threatens to overwhelm cuts in greenhouse gas achieved elsewhere. Critics have also targeted frequent-flier programs like the one of which I am a top-level member.

International air travel results in yet more “free” air travel with the accumulation of points. The perk of frequent flier miles often leads to personal trips that would not be taken if the ticket had to be paid with personal funds. That’s a hard cycle to break. I, for one, hope the biofuels catch on quickly

Cayman Islands News

Mount Trashmore – a mountain of resource?
Posted on Thu, 03/21/2013 – 08:35 in Viewpoint

Rolf Stein

In the many years that islanders have sought to resolve the environmental
debacle that looms over the capital, various schemes have been proposed
for dealing with Mount Trashmore; from shipping scrap metal to China,
constructing a dry ski slope and setting up a new waste site at Bodden
Town. The WISE website outlines a plethora of sustainable alternatives,
which, if applied, amount to a comprehensive and sustainable waste
management solution for the future whilst also proposing options for
returning the George Town site to its natural, pre-rubbish dump state
through landfill mining.

During the time that this debate has been raging there has been a
complete revolution in conventional wisdom about waste management. Waste
is becoming increasingly viewed as a revenue-generating resource rather
than as something to be thrown away. New technologies are driving the
change in perception as they have created the means to transform waste
into a resource thereby creating the means for sustainable waste
management and safe, clean landfill removal.

Landfill sites can now be mined for their valuable recyclates because
rubbish dumps and historic waste streams contain concentrations of
valuable materials such as metals that will be processed and recycled.
That which cannot be recycled can be converted into renewable power and
heat using advanced conversion technologies. These new technologies
ensure that the maximum value is extracted from this residual material
enabling the return of landfill sites to their natural state for
development of community use.  Indeed, Advanced Plasma Power (APP) is
pioneering such a landfill mining project in Belgium and such an approach
could be applied to Trashmore.

Taking this view of waste is a complete paradigm shift. Rather than
treating waste as a problem to be disposed of, and relying on
rapidly-depleting sources of fossil fuels to meet our mounting energy
needs, advanced conversion technologies can convert municipal, commercial
and industrial waste into clean, sustainable energy.  Advanced
gasification plants are very compact and are designed to sit
unobtrusively on the edge of towns taking the waste that the town
generates and providing vital, proximate and cost effective resources in
return. Visual and environmental impact are kept to a minimum.

APP’s Gasplasma process is a game changer for managing waste in the built
environment as it produces no waste outputs and has low emissions. APP’s
plasma conversion delivers such a clean, high quality syngas that it can
be used directly in efficient gas engines and gas turbines to generate
power. The process generates no waste outputs as any ash is vitrified
into an environmentally stable and saleable construction product –

Furthermore, the output from the plants need not be limited to power; APP
is also pioneering the way in developing next generation waste to fuel
plants. The clean gas produced by the process can also be used to
substitute natural gas or other fuel gas.

Aligning waste policy with renewable energy policy will allow a
sustainable and cost-effective alternative to current practices.  In the
case of the Cayman Islands the benefits are even more profound. The
ever-growing toxic mound leeches into the water and the surrounding
environs, threatening the environment, tourism and possibly even human
health. The solution really needn’t be that complicated.

Rolf Stein is Chief Executive of Advanced Plasma Power

SEN visits Macau

The Secretary for the Environment, Mr Wong Kam-sing, leading a Hong Kong Special Administrative Government delegation, today (March 21) attended the 2013 Macao International Environmental Co-operation Forum & Exhibition to learn more about the green business opportunities brought about by the latest environmental technologies.

In the morning, Mr Wong attended the forum’s opening ceremony and its keynote address session, and toured the exhibition booths.

He also called on the Chief Executive of the Macau Special Administrative Region, Mr Chui Sai-on, to exchange views on strengthening co-operation in environmental protection between Hong Kong and Macau. He then attended a networking luncheon.

In the afternoon, Mr Wong visited the Macao Cotai Ecological Zones to see the wetland and mangrove conservation work that has taken place there. The ecological zone’s natural habitat nurtures a wide range of plants and animals, with many bird species also resident in the area.

Mr Wong then visited the Macao Refuse Incineration Plant to learn more about Macau’s waste management. Apart from treating waste, the facility recovers heat energy from waste combustion to generate electricity for Macau’s power grid.

Mr Wong and the delegation will conclude the visit and return to Hong Kong in the evening.

Ends/Thursday, March 21, 2013
Issued at HKT 18:16

Hong Kong Air Pollutant Emission Inventory

Download PDF : Hong Kong Air Pollutant Emission Inventory

Light pollution in Hong Kong ‘worst on the planet’

Wednesday, 20 March, 2013, 12:00am

News›Hong Kong


Cheung Chi-fai

It’s 1,200 times brighter over Tsim Sha Tsui than a normal dark sky, three-year study finds, posing a danger to health and wildlife

Hong Kong is believed to be the world’s worst city for light pollution, with levels in Tsim Sha Tsui 1,200 times brighter than a normal dark sky.

The findings were described as shocking by survey leader Dr Jason Pun Chun-shing, of the Department of Physics at the University of Hong Kong.

He said he could find nowhere else on earth as badly affected.

From the notorious hotspot of Tsim Sha Tsui to the remote Sai Kung countryside, the researchers found excessive brightness of varying degrees that scientists said could damage health and wildlife.

Unlike major cities elsewhere – including London, Frankfurt, Sydney and Shanghai – Hong Kong has no laws to control external lighting.

But Secretary for the Environment Wong Kam-sing said he hoped a government task force on light pollution could come up with proposals for more “regulatory elements” for public discussion in the middle of this year.

He did not say if he meant legislation.


In the world’s largest light pollution study, scientists collected more than five million brightness measurements at 18 monitoring stations over the past three years. They used an instrument known as a Sky Quality Meter installed on roofs. The worst reading was at the Space Museum in Tsim Sha Tsui from 8.30pm to 11pm, which was 1,200 times the International Astronomical Union standard.

Brightness started to dip after 11pm when lights gradually went out. Tsim Sha Tsui residents once threatened to take developers to court over excessive lights.

Even at the Astropark stargazing facility near High Island Reservoir – where most would expect a natural dark sky – the brightness was still 20 times the standard. Health specialists say light pollution could disrupt the biological clock and affect brain and hormone function.

Pun said that in some European cities like Madrid and Florence, the readings were normally below 100 times the standard.

He said energy-wasting signboards or spotlights that usually point upwards could generally be blamed in Hong Kong.

He added: “Lighting is supposed to provide safety and security for people’s daily life. Lights are for human use and not for the sky. But what we see is that many lights are pointing to the sky.”

Lighting is supposed to provide safety and security for people’s daily life. Lights are for human use and not for the sky. But what we see is that many lights are pointing to the sky

Conservationists were alarmed by the reading at the Wetland Park in Tin Shui Wai at 130 times the standard.

Hong Kong Entomological Society chairman Yiu Vor said he feared the brightness would affect the breeding of fireflies, including the endemic bent-winged firefly, which relied on light signals to mate.

“They might not be able to notice the signals in a bright environment or they simply release the signal less frequently. This would affect their continuing survival.” Yiu said insects that relied on moonlight to navigate could also be affected.

Pun said Hong Kong needed tougher measures to curb light pollution, instead of relying on voluntary technical guidelines.

Sydney requires all private illuminated signs to be scrutinised by the city council.

London also makes such nuisances a statutory offence carrying a fine or even imprisonment.


Light Pollution

Hong Kong


More on this:

Light pollution task force at impasse after 20 months [2]

Resetting the body clock can affect health [3]

Source URL (retrieved on Mar 20th 2013, 6:07am):


The Great Green Con no. 1: The hard proof that finally shows global warming forecasts that are costing you billions were WRONG all along

No, the world ISN’T getting warmer (as you may have noticed). Now we reveal the official data that’s making scientists suddenly change their minds about climate doom. So will eco-funded MPs stop waging a green crusade with your money? Well… what do YOU think?

The Mail on Sunday today presents irrefutable evidence that official predictions of global climate warming have been catastrophically flawed.

The graph on this page blows apart the ‘scientific basis’ for Britain reshaping its entire economy and spending billions in taxes and subsidies in order to cut emissions of greenhouse gases. These moves have already added £100 a year to household energy bills.

global warming graphglobal warming graph

Steadily climbing orange and red bands on the graph show the computer predictions of world temperatures used by the official United Nations’ Intergovernmental Panel on Climate Change (IPCC).

The estimates – given with 75 per cent and 95 per cent certainty – suggest only a five per cent chance of the real temperature falling outside both bands.

But when the latest official global temperature figures from the Met Office are placed over the predictions, they show how wrong the estimates have been, to the point of falling out of the ‘95 per cent’ band completely.

In 1977 we were warned of the 'next ice age', now we are warned that the planet is getting dangerously hot Varying fears: In 1977 we were warned of the ‘next ice age’, now we are warned that the planet is getting dangerously hot

The graph shows in incontrovertible detail how the speed of global warming has been massively overestimated. Yet those forecasts have had a ruinous impact on the bills we pay, from heating to car fuel to huge sums paid by councils to reduce carbon emissions.

The eco-debate was, in effect, hijacked by false data. The forecasts have also forced jobs abroad as manufacturers relocate to places with no emissions targets.

A version of the graph appears in a leaked draft of the IPCC’s landmark Fifth Assessment Report due out later this year. It comes as leading climate scientists begin to admit that their worst fears about global warming will not be realised.

Academics are revising their views after acknowledging the miscalculation. Last night Myles Allen, Oxford University’s Professor of Geosystem Science, said that until recently he believed the world might be on course for a catastrophic temperature rise of more than five degrees this century.

But he now says: ‘The odds have come down,’ – adding that warming is likely to be significantly lower.
Prof Allen says higher estimates are now ‘looking iffy’.

The graph confirms there has been no statistically significant increase in the world’s average temperature since January 1997 – as this newspaper first disclosed last year.

At the end of last year the Met Office revised its ten-year forecast predicting a succession of years breaking records for warmth. It now says the pause in warming will last until at least 2017. A glance at the graph will confirm that the world will be cooler than even the coolest scenario predicted.


Its source is impeccable. The line showing world temperatures comes from the Met Office ‘HadCRUT4’ database, which contains readings from more than 30,000 measuring posts. This was added to the 75 and 95 per cent certainty bands to produce the graph by a group that amalgamates the work of 20 climate model centres working for the IPCC.

Predictions of global warming, based on scientists’ forecasts of how  fast increasing CO2 levels would cause temperatures to rise, directly led to Britain’s Climate Change Act. This commits the UK to cut emissions by 80 per cent by 2050.


In the Seventies, scientists and policymakers were just as concerned about a looming ‘ice age’ as they have been lately about global warming – as the Time magazine cover  pictured here illustrates.

Temperatures had been falling since the beginning of the Forties. Professors warned that the trend would continue and food crises were going to get worse because of shorter growing seasons.

Newsweek magazine reported that evidence of cooling was so strong ‘meteorologists are hard-pressed to keep up with it’. But, it lamented, ‘scientists see few signs that government leaders anywhere are even prepared to take the simple measures of introducing the variables of climatic uncertainty into economic projections’. It said the planet was already ‘a sixth of the way towards  the next ice age’.

While recently every kind of extreme weather event has been blamed on warming, in the Seventies the culprit was cooling. One article predicted ‘the most devastating outbreak of tornadoes ever recorded’, along with ‘droughts, floods, extended dry spells and long freezes’.

The current Energy Bill is set to increase subsidies for wind turbines to £7.6 billion a year – leading to a combined cost of £110 billion. Motorists will soon see a further 3p per litre rise in the cost of petrol because this now has to contain ‘biofuel’ ethanol.

Many scientists say the pause, and new research into factors such as smoke particles and ocean cycles, has made them rethink what is termed ‘climate sensitivity’ – how much the world will warm for a given level of CO2.

Yesterday Piers Forster, Climate Change Professor at Leeds University, said: ‘The fact that global surface temperatures haven’t risen in the last 15 years, combined with good knowledge of the terms changing climate, make the high estimates unlikely.’

And Professor Judith Curry, head of climate science at the prestigious Georgia Institute of Technology, said: ‘The models are running too hot. The flat trend in global surface temperatures may continue for another decade or two.’

James Annan, of Frontier Research For Global Change, a prominent ‘warmist’, recently said high estimates for climate sensitivity now look ‘increasingly untenable’, with the true figure likely to be about half of the IPCC prediction in its last report in 2007.

Avowed climate sceptics are more  unequivocal. Dr David Whitehouse, author of a new report on the pause published on Friday by Lord Lawson’s Global Warming Policy Foundation, said: ‘This changes everything. It means we have much longer to work things out. Global warming should no longer be the main determinant of anyone’s economic or energy policy.’

I said the end wasn’t nigh… and it cost me my BBC career says TV’s first environmentalist, David Bellamy

Former BBC Botanist David Bellamy said that he was regarded as heretical for not toeing the line on global warmingChallenged the orthodoxy: Former BBC Botanist David Bellamy said that he was regarded as heretical for not toeing the line on global warming

This graph shows the end of the world isn’t nigh. But for anyone – like myself – who has been vilified for holding such an unfashionable view, possibly the most important thing about it is its source: the United Nations’ Intergovernmental Panel on Climate Change (IPCC).

Since its creation in 1988, the IPCC has been sounding the alarm about man-made global warming. Yet here, in a draft of its latest report, is a diagram overlaying the observed temperature of the earth on its predictions.

The graph shows a world stubbornly refusing to warm. Indeed, it shows the world is soon set to be cooler.

The awkward fact is that the earth has warmed just 0.5 degrees over the past 50 years. And Met Office records show that for the past 16 years temperatures have plateaued and, if anything, are going down.

As the graph shows, the longer this goes on, the more the actual, real-world temperature record will diverge from the IPCC’s doom-laden prediction.

Yet this prediction is used to justify the ugly wind farms spoiling our countryside and billions in unnecessary ‘green’ taxes that make our industry less competitive and add up to £100 a year to household energy bills.

Man-made global warming has become scientific orthodoxy, with no room for dissent. Tragically, the traditional caution of my brethren has gone out of the window along with the concept of sceptical peer reviewing to test new theories.

Opponents of man-made global warming are regarded as dangerous heretics, as I learnt to my cost. Soon after the IPCC was created, I was invited to what is now the Met Office’s Hadley Centre for Climate Prediction and Research in Exeter to hear a presentation on global warming.

As the face of natural history on the BBC and a science academic, they wanted to enrol me in their cause. But when I read the so-called evidence, I realised it was flawed and refused to ‘sign up’.

I rapidly found myself cast out from the BBC and the wider scientific community. When I helped some children campaign against a wind farm as part of a Blue Peter programme, I was publicly vilified. Abusive emails criticised me. I realised my career at the BBC was over.

But scientific theory should be tested. That’s why I question the science which casts carbon as the villain that will bring about the end of the world.

David Bellamy argues that we should be able to test theories about global warming and that the world can live with fluctuations of carbon levels in the airOpen discussion: David Bellamy argues that we should be able to test theories about global warming and that the world can live with fluctuations of carbon levels in the air

Geology tells us that fossil fuels are predominantly carbon which was part of our atmosphere before being locked away in the earth millions of years ago. At that time, there were more than 4,000 carbon parts per million (ppm) in the atmosphere. Over time this has been as low as 270ppm and is now about 385ppm.

It is obvious the world can live with these fluctuations in the level of atmospheric carbon.
There is a correlation between temperature and CO2, but some of my colleagues have put the cart before the horse.

The evidence shows CO2 levels follow temperature, not the other way around.
Indeed, there may be many factors that determine our climate. Australian scientist David Archibald has shown  a remarkable correlation between the sun’s activity and our climate over the past 300 years. Climate scientists insist we must accept the ‘carbon’ orthodoxy or be cast into the wilderness.

But the scientists behind  the theory have a vested interest – it’s a great way to justify new taxes, get more money and guarantee themselves more work.

The reality is that man-made global warming is a myth: the global temperature is well within life’s limits and, indeed, the present day is cooler by comparison to much of Earth’s history. Perhaps this will be the moment that this fact becomes the new scientific orthodoxy.
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Street cleaners send waste for recycling to landfills

Sunday, 17 March, 2013, 12:00am

News›Hong Kong


Keith Wallis

Government-paid street sweepers have been caught emptying recycling bins and dumping their contents with general waste destined for landfills.

Video taken by the Sunday Morning Post revealed the illegal activity, which is torpedoing public recycling efforts and denying the government’s recycling contractor revenue from the sale of plastics, paper and metals for reprocessing.

In the footage, operatives in blue overalls and yellow high visibility vests, employed on government cleaning contracts, open the doors of on-street recycling boxes and pull out the collection bins.

They then mix material for recycling with rubbish from general waste bins and dump the black bags with other rubbish bags on their trolleys.

They close the boxes and continue sweeping the streets.

Such activities have been caught on camera in Causeway Bay and Wan Chai and appear to have increased in recent weeks.

In the past, such bins were typically the target of scavengers, hunting for material to sell to backstreet recycling operators.

It was also accepted that operatives would sometimes remove material hanging outside the bins or lying on the ground. But the video footage reveals street sweepers are now opening the bins to remove their entire contents, sometimes less than an hour before the recycling contractor is due to arrive.

A Food and Environmental Hygiene Department spokesman said: “Our street cleansing contractors are not allowed to tamper with the content of the recyclables collection bins.” He added that tampering with the boxes “without a reasonable excuse” was an offence with a maximum fine of HK$5,000.

On Kee Metal Company was awarded contracts totalling HK$12.92 million to collect plastics, metal and paper from recycling boxes on Hong Kong Island, Kowloon and the New Territories. The contracts began on August 1 last year and will expire on July 31 next year.

Project manager at On Kee Anthony Ho could not estimate how much revenue the business was losing at the hands of street sweepers.

Scavengers tend to get about HK$1 per kilogram for waste paper and steel sold to backstreet recyclers, while aluminium cans fetch about 10 cents each.

A departmental spokesman said an average of about 44 tonnes of waste paper, 1.3 tonnes of metals and 14 tonnes of plastic was collected each month last year.

Ho said material collected under the department’s contract represented 3 per cent of the total amount of plastics, paper and other recyclables collected from organisations, including the airport, Jockey Club, hospitals, hotels and supermarkets.

He said On Kee would report the situation with street sweepers to the department.

A departmental spokesman said: “We have received no such complaints from the contractor since the commencement of the contract.”



Waste Management

Public Services

Recycling Bin



Source URL (retrieved on Mar 17th 2013, 7:10am):

Making waste a resource and moving towards a truly circular economy

Download PDF : SPEECH-13-211_EN

Greenhouse Gas Emissions

NASA – Water Vapor Confirmed as Major Player in Climate Change

Water Vapor Confirmed as Major Player in Climate Change


Still from animation showing global distribution of atmospheric water vapor

The distribution of atmospheric water vapor, a significant greenhouse gas, varies across the globe. During the summer and fall of 2005, this visualization shows that most vapor collects at tropical latitudes, particularly over south Asia, where monsoon thunderstorms swept the gas some 2 miles above the land.
Credit: NASA
> Watch video
Water vapor is known to be Earth’s most abundant greenhouse gas, but the extent of its contribution to global warming has been debated. Using recent NASA satellite data, researchers have estimated more precisely than ever the heat-trapping effect of water in the air, validating the role of the gas as a critical component of climate change.

Andrew Dessler and colleagues from Texas A&M University in College Station confirmed that the heat-amplifying effect of water vapor is potent enough to double the climate warming caused by increased levels of carbon dioxide in the atmosphere.

With new observations, the scientists confirmed experimentally what existing climate models had anticipated theoretically. The research team used novel data from the Atmospheric Infrared Sounder (AIRS) on NASA’s Aqua satellite to measure precisely the humidity throughout the lowest 10 miles of the atmosphere. That information was combined with global observations of shifts in temperature, allowing researchers to build a comprehensive picture of the interplay between water vapor, carbon dioxide, and other atmosphere-warming gases. The NASA-funded research was published recently in the American Geophysical Union’s Geophysical Research Letters.

“Everyone agrees that if you add carbon dioxide to the atmosphere, then warming will result,” Dessler said. “So the real question is, how much warming?”

The answer can be found by estimating the magnitude of water vapor feedback. Increasing water vapor leads to warmer temperatures, which causes more water vapor to be absorbed into the air. Warming and water absorption increase in a spiraling cycle.
Graph showing that the energy trapped by water peaks near the equator
Based on climate variations between 2003 and 2008, the energy trapped by water vapor is shown from southern to northern latitudes, peaking near the equator.
Credit: Andrew Dessler
> Larger image
Water vapor feedback can also amplify the warming effect of other greenhouse gases, such that the warming brought about by increased carbon dioxide allows more water vapor to enter the atmosphere.

“The difference in an atmosphere with a strong water vapor feedback and one with a weak feedback is enormous,” Dessler said.

Climate models have estimated the strength of water vapor feedback, but until now the record of water vapor data was not sophisticated enough to provide a comprehensive view of at how water vapor responds to changes in Earth’s surface temperature. That’s because instruments on the ground and previous space-based could not measure water vapor at all altitudes in Earth’s troposphere — the layer of the atmosphere that extends from Earth’s surface to about 10 miles in altitude.

AIRS is the first instrument to distinguish differences in the amount of water vapor at all altitudes within the troposphere. Using data from AIRS, the team observed how atmospheric water vapor reacted to shifts in surface temperatures between 2003 and 2008. By determining how humidity changed with surface temperature, the team could compute the average global strength of the water vapor feedback.

“This new data set shows that as surface temperature increases, so does atmospheric humidity,” Dessler said. “Dumping greenhouse gases into the atmosphere makes the atmosphere more humid. And since water vapor is itself a greenhouse gas, the increase in humidity amplifies the warming from carbon dioxide.”

Specifically, the team found that if Earth warms 1.8 degrees Fahrenheit, the associated increase in water vapor will trap an extra 2 Watts of energy per square meter (about 11 square feet).

“That number may not sound like much, but add up all of that energy over the entire Earth surface and you find that water vapor is trapping a lot of energy,” Dessler said. “We now think the water vapor feedback is extraordinarily strong, capable of doubling the warming due to carbon dioxide alone.”

Because the new precise observations agree with existing assessments of water vapor’s impact, researchers are more confident than ever in model predictions that Earth’s leading greenhouse gas will contribute to a temperature rise of a few degrees by the end of the century.

“This study confirms that what was predicted by the models is really happening in the atmosphere,” said Eric Fetzer, an atmospheric scientist who works with AIRS data at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “Water vapor is the big player in the atmosphere as far as climate is concerned.”

Related Links:

> Will Runaway Water Warm the World?
> Atmospheric Infrared Sounder (AIRS) Web page

Kathryn Hansen
NASA’s Goddard Space Flight Center

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