Global Warming......

[KnottyKnanna]

Thanks Wayne.....

Maybe we can stay on topic this time.....

[hydrology_joe]

Personally, I always wondered how much gas one large dinosaur could put out, compared to herds of cows spewing methane now.

What about the herds of millions of bison that used to roam the plains? Thats a lot of ruminants!

[hydrology_joe]

Increases in greenhouse gases are not the only cause of global warming! To blame all of global warming solely on man is both naive and egotistical!

The truth about global warming - it's the Sun that's to blame

Global warming has finally been explained: the Earth is getting hotter because the Sun is burning more brightly than at any time during the past 1,000 years, according to new research.

A study by Swiss and German scientists suggests that increasing radiation from the sun is responsible for recent global climate changes.

Dr Sami Solanki, the director of the renowned Max Planck Institute for Solar System Research in Gottingen, Germany, who led the research, said: "The Sun has been at its strongest over the past 60 years and may now be affecting global temperatures.

advertisement"The Sun is in a changed state. It is brighter than it was a few hundred years ago and this brightening started relatively recently - in the last 100 to 150 years."

Dr Solanki said that the brighter Sun and higher levels of "greenhouse gases", such as carbon dioxide, both contributed to the change in the Earth's temperature but it was impossible to say which had the greater impact.

Average global temperatures have increased by about 0.2 deg Celsius over the past 20 years and are widely believed to be responsible for new extremes in weather patterns. After pressure from environmentalists, politicians agreed the Kyoto Protocol in 1997, promising to limit greenhouse gas emissions between 2008 and 2012. Britain ratified the protocol in 2002 and said it would cut emissions by 12.5 per cent from 1990 levels.

Globally, 1997, 1998 and 2002 were the hottest years since worldwide weather records were first collated in 1860.

Most scientists agree that greenhouse gases from fossil fuels have contributed to the warming of the planet in the past few decades but have questioned whether a brighter Sun is also responsible for rising temperatures.

To determine the Sun's role in global warming, Dr Solanki's research team measured magnetic zones on the Sun's surface known as sunspots, which are believed to intensify the Sun's energy output.

The team studied sunspot data going back several hundred years. They found that a dearth of sunspots signalled a cold period - which could last up to 50 years - but that over the past century their numbers had increased as the Earth's climate grew steadily warmer. The scientists also compared data from ice samples collected during an expedition to Greenland in 1991. The most recent samples contained the lowest recorded levels of beryllium 10 for more than 1,000 years. Beryllium 10 is a particle created by cosmic rays that decreases in the Earth's atmosphere as the magnetic energy from the Sun increases. Scientists can currently trace beryllium 10 levels back 1,150 years.

Dr Solanki does not know what is causing the Sun to burn brighter now or how long this cycle would last.

He says that the increased solar brightness over the past 20 years has not been enough to cause the observed climate changes but believes that the impact of more intense sunshine on the ozone layer and on cloud cover could be affecting the climate more than the sunlight itself.

Dr Bill Burrows, a climatologist and a member of the Royal Meteorological Society, welcomed Dr Solanki's research. "While the established view remains that the sun cannot be responsible for all the climate changes we have seen in the past 50 years or so, this study is certainly significant," he said.

"It shows that there is enough happening on the solar front to merit further research. Perhaps we are devoting too many resources to correcting human effects on the climate without being sure that we are the major contributor."

Dr David Viner, the senior research scientist at the University of East Anglia's climatic research unit, said the research showed that the sun did have an effect on global warming.

He added, however, that the study also showed that over the past 20 years the number of sunspots had remained roughly constant, while the Earth's temperature had continued to increase.

This suggested that over the past 20 years, human activities such as the burning of fossil fuels and deforestation had begun to dominate "the natural factors involved in climate change", he said.

Dr Gareth Jones, a climate researcher at the Met Office, said that Dr Solanki's findings were inconclusive because the study had not incorporated other potential climate change factors.

"The Sun's radiance may well have an impact on climate change but it needs to be looked at in conjunction with other factors such as greenhouse gases, sulphate aerosols and volcano activity," he said. The research adds weight to the views of David Bellamy, the conservationist. "Global warming - at least the modern nightmare version - is a myth," he said. "I am sure of it and so are a growing number of scientists. But what is really worrying is that the world's politicians and policy-makers are not.

"Instead, they have an unshakeable faith in what has, unfortunately, become one of the central credos of the environmental movement: humans burn fossil fuels, which release increased levels of carbon dioxide - the principal so-called greenhouse gas - into the atmosphere, causing the atmosphere to heat up. They say this is global warming: I say this is poppycock."

[bigalpha]

To determine the Sun's role in global warming, Dr Solanki's research team measured magnetic zones on the Sun's surface known as sunspots, which are believed to intensify the Sun's energy output.

They just think that sunspots are believed to intensify the Sun's energy output; but they have no concrete proof to this?

"It shows that there is enough happening on the solar front to merit further research. Perhaps we are devoting too many resources to correcting human effects on the climate without being sure that we are the major contributor."

Yes, I agree. We need to do more research to see if the Sun is a (major) contributor to the heating of the earth. It may be that the Sun is the major shareholder in the heating game. However, to say that "we are devoting too many resources to correcting human effects on the climate" is asinine. We should be pushing to stifle our effects on the climate as that would result in a cleaner environment (i.e. less coal and oil burning, etc).

[Mike Cato]

Woah, BigA!!!

Careful, you might find yourself feeling comfy on that soapbox.

Down boy!

[Teresa]

[
Yes, I agree. We need to do more research to see if the Sun is a (major) contributor to the heating of the earth.

BigA-- the sun is responsible directly or indirectly for something like 95%+ of all surface heat on earth. I found that out in eighth grade. However, humans are largely responsible for excess perturbations and particulates in the atmosphere on any given day (exceptions, of course for volcanoes, rockslides, violent ocean waves stirring up H2O into the air and cow flatulence). It is the condition of the atmosphere which affects how that heat behaves after it arrives. (Does it bounce off into space? Does it get trapped beneath clouds? (greenhouse effect). Atmospheric haze is caused by a lot of things-- atmospheric disturbance by jet planes, power plants, car exhaust, presence of water vapor, road dust, an elephant stampede, sneezing) but the most controllable part of atmospheric haze and particulates are human use of fossil fuels. If you know how to tame a volcano, let the rest of us know.

The concept that global warming is caused because the sun is getting hotter (it will continue to do so, if you know anything about the life cycle of a star) is a copout. We're all dependent on the sun, anyway, and not much we can do it but travel to another solar system if the sun misbehaves. *IF* we can get the earth to lose heat equal to what is coming in we've got the problem whipped. But if we wrap ourselves in a cloudy insulating cocoon, we've got no one to blame for it but ourselves and a few volcanoes and cows.

[hydrology_joe]

They just think that sunspots are believed to intensify the Sun's energy output; but they have no concrete proof to this?

bigalpha,

I know Wikipedia isn't the best source for information but their article on Sun Spots is very concise. Here is a clip from the site...

The number of sunspots has been found to correlate with the intensity of solar radiation over the period - since 1979 - when satellite measurements of radiation are available. Since sunspots are dark it is natural to assume that more sunspots means less solar radiation. However, the surrounding areas are brighter and the overall effect is that more sunspots means a brighter sun.

The concept that global warming is caused because the sun is getting hotter (it will continue to do so, if you know anything about the life cycle of a star) is a copout. We're all dependent on the sun, anyway, and not much we can do it but travel to another solar system if the sun misbehaves. *IF* we can get the earth to lose heat equal to what is coming in we've got the problem whipped. But if we wrap ourselves in a cloudy insulating cocoon, we've got no one to blame for it but ourselves and a few volcanoes and cows.

If you want to believe that the sun getting hotter as THE cause for global warming is a copout, then explain this...
CO2 and Water Vapor produce no heat of their own and CO2 and water vapor BLOCKS incoming solar radiation (just the same as it blocks radiation from leaving). If that radiation is NOT coming into the earth because it is being blocked, then how is the earth warming? A. Increased Solar Radiation!

[bigalpha]

Woah, BigA!!!

Careful, you might find yourself feeling comfy on that soapbox.

Down boy!

sorry

[bigalpha]

Teresa -

Not trying to offend you, but it's been a long time since you were in the 8th grade. Do you have a source for the 95%? It may very well be impossible to equal heat coming in and out of the atmosphere if we are in a natural warming trend anyways.

Joe -

So, if H20 and C02 block incoming radiation, then theoretically; increased amounts of these in the atmosphere should lower our global temperature? If these two compounds block incoming solar radiation; and the sun is increasing it's radiation thereby heating up the earth - shouldn't we increase the amount of H20 and CO2 to make sure the earth's temperature doesn't increase?

[Marlatt]

...explain this...
CO2 and Water Vapor produce no heat of their own and CO2 and water vapor BLOCKS incoming solar radiation (just the same as it blocks radiation from leaving).

Just as a point of reference, the majority of the insolation is short-wave radiation, primarily in the visible spectrum, while the emissive radiation is largely IR. CO2 and water vapor are much less transparent to longer wave radiation.

swm

[Teresa]

First, some figures:

mW/m2=milliwatts/meter squared
kW/m2=kilowatts/meter squared

http://zebu.uoregon.edu/disted/ph162/l4.html

Average incoming solar radiation per 24 hrs = 164 w/m2

http://www.answers.com/topic/earth-heat-flow-in
Average outgoing earth heat flow 87 mW/m2

.087/164 =.05% geothermal heat flow to surface vs solar input.

Reason for the 95% figure, vs 99.95% figure derived above:
a)heat flow figures are averages and do not take into account
discrete energy releases such as volcanoes, earthquakes, geyser fields
etc. where earth heat flow events may exceed the 87 mW/m2 by significant amounts. For example: heat flow at Kilauea which has been erupting for 25 years with observed maximums of 8.09 kW/m2 greatly exceed the average. (http://adsabs.harvard.edu/abs/1983Sci...222...47H)

At any given moment, a volcano is erupting and an earthquake is occurring somewhere on the planet, which would make such surface heat input hard to quantify as hard numbers.

b)I'm not a geophysicist, and am willing to give the planet some slop in its functioning.

Even being so data liberal, this still gives the sun a 95-99% advantage in its input to the surface heat flux. My point was: regardless of how the earth is heating, if the atmosphere does not permit the release of that heat into space, we're gonna get warmer. Period. I believe this is a corollary of the GIGO principle: if Garbage comes in, and cannot go out, you get buried in Garbage.

The point being: heat escapes faster through an atmosphere without greenhouse gases than from one with greenhouse gases.

I don't have a problem with the sun getting hotter. It is supposed to. At some time, if we survive as a species (doubtful, IMO) we are going to be fried to a crisp, assuming the sun expands as it grows older--a phenomenon which most astronomers expect to occur over the next few billion years. The sun is not large enough and is of the wrong star class to go nova and explode. It is also presumed to be in stellar middle age. So, we'd better get the lifeboats ready...but there isn't any point to bring the end to life on earth any faster than it is going already.

The original figure of 95% earth surface heat from the sun came from data in
The Peterson Field Guide to the Stars and Planets, by Donald H. Menzel. p.186. Actually, Menzel goes further: saying: "The sun is our source of heat and light." No quibbles about earthly heat sources. When you are looking at things as an astronomer, and you've got figures to back up a 99.95% input, you can make wild statements like that. I actually did a similar series of calculations as above to account for volcanoes, earthquake, geyserfields and radioactivity back in 1970 as an eighth grader. and yes, bigalpha, I still have the term paper.

See also:


http://www.madsci.org/posts/archives/oc ... .Es.r.html


Further references on the topic.

The Galaxy Song by Eric Idle

http://solar-center.stanford.edu/sun-on ... -warm.html

http://earthobservatory.nasa.gov/Library/Oven/

http://dev.nsta.org/ssc/moreinfo.asp?id=947

http://en.wikipedia.org/wiki/Sun

http://terra.nasa.gov/FactSheets/EnergyBalance/

http://www.sciam.com/article.cfm?articl ... 414B7F0000
http://www.astrosociety.org/education/p ... ason3.html

http://www.msnbc.msn.com/id/3077384/

http://genesismission.jpl.nasa.gov/scie ... index.html

http://geothermal.marin.org/pwrheat.html

http://csmres.jmu.edu/geollab/fichter/P ... story.html

http://www.phy6.org/stargaze/Sun7enrg.htm

http://www.geology.sdsu.edu/how_volcano ... /Heat.html

Ranges in heat flow on this map vary from 25 to 150 mW/m2.
http://www.smu.edu/geothermal/heatflow/heatflow.htm

Read the abstract on this one: Note that it says an increase due to propagation *into* the subsurface.
http://esrc.stfx.ca/pdf/halifaxtalk.pdf
http://esrc.stfx.ca/pdf/grl-2.pdf

http://www.atmos.uiuc.edu/earths_atmosp ... nsfer.html
http://www.agu.org/reference/gephys/11_stein.pdf

[bigalpha]

Thanks for the info. There's a lot of really interesting stuff buried in all that.

[Cheryl Jones]

Climate scientists feeling the heat
As public debate deals in absolutes, some experts fear predictions 'have created a monster'
http://www.chron.com/disp/story.mpl/front/4487421.html

A tantalizing snippet:
"...........In their efforts to capture the public's attention, then, have climate scientists oversold global warming? It's probably not a majority view, but a few climate scientists are beginning to question whether some dire predictions push the science too far.

"Some of us are wondering if we have created a monster," says Kevin Vranes, a climate scientist at the University of Colorado......."

[Teresa]

I am a confirmed skeptic. Not whether the earth is warming, not whether there is more CO2, not whether climate is or is not something to keep track of--but if
the climatologists who derive their predictions from computer models have all the data they need to make those predictions, and what the accuracy rate of those predictions will be.

Just heard a professional meteorologist with 40 years experience who both teaches at a good university and does on-air forecasting say, 'I'm not a climatologist. But considering if we forecast accurately more than 48 hours in the future, we think we're doing pretty good--I'd like to know how these guys know what the weather is going to be 100 years from now. A lot can change in 100 years."

Something to think about.

[erebus]

I think weather is not the same as climate, and nobody is predicting "what the weather is going to be 100 years from now."