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Posted

http://physicsweb.org/article/news/6/8/7

Water vapour supplies new climate clues

8 August 2002

 

Our atmosphere and climate is dominated by the effects of water vapour, which strongly absorbs sunlight. But even after decades of study, scientists struggle to explain how water molecules absorb as much solar radiation as they do. Now Thomas Rizzo of the École Polytechnique Fédérale de Lausanne in Switzerland and colleagues hope that their novel study of excited water molecules will solve the discrepancy and improve our understanding of effects such as global warming (A Callegari et al 2002 Science 297 993).

 

Water vapour absorbs radiation at many wavelengths, but it absorbs infrared and ultraviolet radiation - which are strongly emitted by the Sun - particularly well. The different energy transitions in molecules of water vapour allow it to absorb radiation of certain wavelengths, and when light is shone through this vapour and dispersed using a prism, this absorption shows up as dark lines in the resulting spectrum.

 

Many researchers have determined the positions and intensities of these absorption lines by measuring the electric dipole moment of molecules of water vapour. This quantity describes how charge is spread through the molecule, and determines how it absorbs radiation. But the electric dipole moment is tricky to measure using conventional spectroscopy, and the best calculations based on previous results cannot fully explain the observed absorption of solar radiation by water vapour in the atmosphere.

 

The electric dipole moment is directly linked to the 'Stark effect', in which the absorption lines of atoms or molecules split into several thinner lines when an electric field is switched on. Exploiting this effect, Rizzo and colleagues applied an electric field to a collection of water molecules and excited them with a laser pulse.

Posted

http://physicsweb.org/article/news/6/3/8

US physicists studying the El Niño and La Niña climate effects believe that these phenomena may simply be short-term fluctuations in a longer-lasting 'super-Niño' event. David Douglass and colleagues of the University of Rochester and David Clader at the State University of New York at Geneseo have shown that climate data collected on El Niño and La Niña since 1967 closely fit a 'resonant function' with a period of about 15 years. The researchers hope their discovery will help climate experts to identify the geophysical mechanisms that underpin El Niño and La Niña (arXiv.org/abs/physics/0203016).

 

El Niño and La Niña are alternating hot and cold periods in the atmosphere and ocean of the Pacific, each lasting about six months. These effects are monitored by the 'sea surface temperature anomaly' - the deviation in the temperature of a certain region of the Pacific ocean from its average temperature. El Niño and La Niña are defined as a difference of more than 0.4 degrees centigrade that lasts at least five months. The 'southern oscillation index' - the difference in atmospheric pressure between certain points in the Pacific - is also closely linked to El Niño and La Niña.

 

http://physicsweb.org/article/world/14/11/6

Our atmosphere could absorb much more radiation from the Sun than previously thought - with far-reaching consequences for climate modelling and the evaporation and condensation of water.

 

Earlier this year a group of some 70 scientists spent an intense week in the foothills of the Rocky Mountains in Colorado reviewing the current understanding of the radiation budget of the atmosphere. The meeting, the latest in the series of Chapman Conferences organized by the American Geophysical Union, focused on the so-called anomalous absorption of solar radiation in the atmosphere.

 

Evidence gathered over the past 20 years has increasingly shown that the absorption of solar radiation predicted by models is significantly less than the absorption measured experimentally. Current models predict that, on a global average, the atmosphere absorbs about 65 W m-2, whereas observations from the top of the atmosphere and the Earth's surface show that the actual absorption is 95 W m-2. This mismatch of some 30 W m-2 corresponds to about 10% of the globally averaged incoming solar radiation, suggesting that some extra anomalous absorption needs to be added to the models

Posted

Just a bit of history :)

 

http://physicsweb.org/article/world/12/12/6/1

Over 100 years ago, the Swedish chemist Svante Arrhenius first pointed out that the release of carbon dioxide into the atmosphere by the burning of fossil fuels was warming the Earth. At the time, neither he nor anybody else was particularly concerned. Greenhouse gases, such as CO2 , water vapour and methane, absorb infrared radiation emitted from the Earth's surface and radiate the heat back towards the planet. The natural concentrations of these gases increase the temperature of the Earth by about 35 °C, and are thus essential for a habitable planet.

 

In Arrhenius's day, the additional greenhouse warming due to human activities was negligible. However, after continuous measurements of the atmospheric CO2 concentration began in 1957, computations soon showed that the rise in CO2 would lead to a warming of our planet by several degrees if it continued unabated. This temperature rise is comparable with the increase since the last ice age, but was predicted to occur on a 100 year, rather than a 10 000 year, timescale. The implications for regional climate, sea levels, ecology and human living conditions were far from clear

Posted

Thanks Rad-E,

I don't see how CO2 relates to an oil Ice age. At least there is data on CO2 but oil dissapates and there is no data to say mid ocean is covered with a film. Bacteria removes it and chemical reactions change the oil to harmless concentrations of organic compounds or clumps of tar.

Just aman

Posted

Ok, lets get one thing straight, spin gravity, oil induced ice ages, darwin false, anti metal, etc, or for that matter anything I choose as a major topic are MY THEORIES.....ther is no back up. This is all synthetised from OBSERVATIOB..not other peoples words.

 

Yoy have to put observation to theory OK.

 

Seeing no boby knew about global warming, accepted theories, I posted them, seeing that nobody knew about the atmospheres heat account, I posted them.

 

Now please stop telling me I do not know what I am talking about!!!

 

YOU will NOT find these THEORIES ANYWHERE!!!

Posted

Billzilla, forget the theory, there is the photo, that is a real observation!

 

And that isn't the only one :)

Posted

Wrong post thread!

 

Have you heard of the Asian Brown cloud !

Floods in Europe, Russia.

Draught in India and China

Draught in the USA

All fairly extreme weather!

Posted

PRAGUE, Czech Republic (CNN) -- Tens of thousands of people are fleeing the Czech capital of Prague as torrential rains and floods continue to devastate cities and towns across Europe.

 

GAUHATI, India (AP) -- Another 10 people have drowned in swirling floodwaters in Bangladesh and helicopters dropped food and medicine to nearly 5,000 people stranded by floods in eastern India, relief officials said.

 

ISTANBUL, Turkey -- Rescuers are continuing to search for people missing in major storms that have lashed Turkey in recent days.

At least 40 people have died, including six children.

Floods, lightning and landslides have struck central and eastern parts of the country since Tuesday.

 

ROSTOV-ON-DON, Russia -- The death toll from flooding in southern Russia -- the worst in 10 years -- has climbed to 93 with tens of thousands fleeing their devastated homes.

 

http://www.cnn.com/2002/WORLD/asiapcf/south/08/12/asia.haze/index.html

HONG KONG, China, CNN -- A dense blanket of pollution, dubbed the "Asian Brown Cloud," is hovering over South Asia, with scientists warning it could kill millions of people in the region, and pose a global threat.

In the biggest-ever study of the phenomenon, 200 scientists warned that the cloud, estimated to be two miles (three kilometers) thick, is responsible for hundreds of thousands of deaths a year from respiratory disease.

By slashing the sunlight that reaches the ground by 10 to 15 percent, the choking smog has also altered the region's climate, cooling the ground while heating the atmosphere, scientists said on Monday

The potent haze lying over the entire Indian subcontinent -- from Sri Lanka to Afghanistan -- has led to some erratic weather, sparking flooding in Bangladesh, Nepal and northeastern India, but drought in Pakistan and northwestern India.

While haze hovers over other parts of the world, such as above America and Europe, what surprised scientists was just how far the cloud extended, and how much black carbon was in it, according to A P Mitra from India's National Physical Laboratory.

Asia's brown haze is altering the weather,creating acid rain

A cocktail of aerosols, ash, soot and other particles, the haze's reach extends far beyond the study zone of the Indian subcontinent, and towards East and Southeast Asia.

While many scientists once thought that only lighter greenhouse gases, such as carbon dioxide, could travel across the Earth, they now say that aerosol clouds can too.

"Biomass burning" from forest fires, vegetation clearing and fossil fuel was just as much to blame for the shrouding haze as dirty industries from Asia's great cities, the study found.

A large part of the aerosol cloud coms from inefficient cookers, where fuels such as cowdung and kerosene are used to cook food in many parts of Asia, says Mitra.

They discovered not only that the smog cut sunlight, heating the atmosphere, but also that it created acid rain, a serious threat to crops and trees, as well as contaminating oceans and hurting agriculture.

Nobel laureate Paul Crutzen -- one of the first scientists to identify the causes of the hole in the ozone layer and also involved in the U.N. report -- said up to two million people in India alone were dying each year from atmospheric pollution.

But because the lifetime of pollutants are short and they can be rained out, scientists are hopeful that if Asians use more efficient ways of burning fuel, such as better stoves, and cleaner sources of energy, time has not run out.

 

The last is due to LACK of rain to wash the atmosphere.

 

And this is just some of the crazyness :)

Posted

Hasn't this stuff been going on for ages somewhere in the world but since we are in the information age and communist countries are being a little more open that we hear about it all at once?

Somebody has floods and somebody has droughts.

We do need to clean up a lotta crap in the world though.

Just aman

Posted

I agree.

It's mainly to do with improved reporting rather than actual deterioration of the general weather systems.

But I do also agree there is a certain amount of deterioration of the general weather systems, though I could not speculate how much of that is due to human factors and how much is some chaotic variation.

I suspect that the true lies somewhere between the tree-huggers shouts of doom, and the fat bloke who doesn't care.

Posted

Africa, Australia, Tasmania, India all have drought.

 

Yes it has all happened before, nothing unusual about the individual events, it is just the extent and extreme nature that is common to each.

 

Certainly insurance companies are in trouble, governments are anxious..

 

If we didn't have the technology we have now, this world wide chaos would be tragic for many be half the population of the world!

:)

Posted

We got lots of rain today in Nebraska. It will normalize soon. Just a bad bump in the road.

Just aman

Posted

You are right Zarkov about the facts of lots of threats to the enviroment. Somebody needs to ring a loud bell.

:uhh: :uhh: :uhh: :uhh: :uhh:

I just personally don't see the threat of microscopic oil layers as you describe them.

Just aman

Posted

I suspect Nature is ringing this bell loud and clear, Aman. Money has to be put aside and all of us should get together and think about our very SURVIVAL!!

Posted

The latest New scientist p13 :-Global warming and cosmic rays!

 

" if Greenhouse Gases were sole heating mechanisms, the Earth's surface and atmosphere would heat up at the same rate- satellite measurements show that this is not happening"

 

"while the surface of the planet has warmed by 0.6 C over the last centuary, the lower 8 kms of the atmosphere has warmed little, if at all."

 

They say, data from the last 20 years has backed up that the Sun has become more active, cosmic rays should reduce cloud cover if the model presented was correct, but low altitude cloud cover has dropped .

 

This is due to oil on the water!

Posted

That was a pretty big leap in logic to a conclusion. If oil coats so many things, how come stuff rusts? Just curious.

Just aman

Posted

OIl is unstable anywhere. >:)

 

In my world everything must happen!

 

Where is your cheer squad :) :)

Posted

CAMP SPRINGS, Maryland (CNN) -- An extraordinary drought and near-record warm temperatures stretched across the United States in July, the National Oceanic and Atmospheric Administration said Wednesday.

 

NOAA's monthly drought assessment placed 49 percent of the contiguous United States in "moderate to severe" drought conditions -- due in part to the fifth-warmest July on record.

 

It goes on to say 6 states are the driest ever!

 

In Australia we have a long ongoing drought, searing sun, and little cloud!

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