Posted on 06/19/2009 9:50:19 PM PDT by neverdem
Particles cool down the climate, but to which extent? This has remained an unanswered question for scientists. A new article in Science by Gunnar Myhre at CICERO, Sweden, brings the scientific community a step closer to solving the mystery.
There is large scientific agreement that human made emissions of CO2 and other gasses give global warming. But human activity doesn’t just cause gas emissions. Burning of fossil fuels and biomass also causes emissions of the particle black carbon. Other kinds of particles are formed in the atmosphere as a cause of human made emissions.
Particles, also named aerosols, are today one of the main reasons for the uncertainty about how humans affect the global climate. Aerosols like sulfur, nitrate, and organic carbon are formed in the atmosphere and cause global cooling. Thereby they contribute to mask parts of the human induced global warming. On the other hand, black carbon absorbs radiation and thereby has a warming effect on the earth’s climate.
Models and observations
The average climate effect from particles is a cooling effect. But to which extent particles cool down the climate, has remained an unanswered question for scientists.
“An important reason for this uncertainty is that estimates of the climate effect based on observations and models have not coincided”, Gunnar Myhre explained.
“For scientists, this has been frustrating. It has given us less faith in our understanding of the models and in our understanding of the direct aerosol effect”.
Defect in the estimates
Based on satellite observations, estimates are made of the climate effect from aerosols. If these estimates were correct, aerosols would have had a stronger cooling effect than the models show and thereby to an even larger extent have masked the global warming. Some estimates even show that aerosols have masked as much as 50 percent of the warming from CO2.
But Myhre’s article now points at what might have been a defect in these estimates. By doing this, he brings scientists a big step closer to the explanation of the discrepancy between models and estimates from observations.
“The estimates are not able to consider that the share of black carbon particles has increased by a much faster rate than the total number of particles. This can explain the main discrepancy we have seen between estimates from observations and models”, Myhre said.
Weaker cooling effect
According to Myhre’s article, the models have until now given the best picture of the climate effect from aerosols. The cooling effect from aerosols looks like being a bit weaker than the estimates from observations would say.
“What I have done, is a small contribution to our understanding of the human influence on climate change. The more we understand, the better prognoses can we give for future temperatures”, Myhre said.
Even though particles until now have masked part of the global warming, they will not do this to the same extent in the future.
”Particles only stay in the atmosphere for a few days. If the production of particles should remain constant in the future, the amount of particles in the atmosphere would also be constant”, Myhre said.
”CO2 is different. CO2 stays in the atmosphere for several hundred years. With constant CO2 emissions, the concentration continues to increase and the warming will accelerate strongly in the future. The aereosols will then be able to mask a relatively smaller part of the global warming”, Gunnar Myhre said.
climate ping
Mist me?
My question is pretty simple, really. By direct measurements, global temperatures have been falling for the past 6 years. By direct measurements, CO2 levels have been rising for the past 6 years. Anyone find that strangely opposite to what the global warmists are telling us?
Underlying this article's focus is that people, as a species, are bad (for who?). Regards, R.
Lemmings over a cliff.
“The average climate effect from particles is a cooling effect. But to which extent particles cool down the climate, has remained an unanswered question for scientists.”
Sort of like the extent to which CO2 and other “greenhouse” gases affect warming the planet also remains an unanswered question for real scientists.
6 years really isn’t a trend. These things go up and down.
30 or 40 years is a trend.
I personally have no idea what’s going on with the climate and how much of it is influenced by human activity. And based on all of the reading I’ve done (which is a reasonable amount) that seems to be probably about the best and most honest “opinion” out there.
In any event, we certainly don’t seem to me to have enough evidence of “anthropogenic global warming” to warrant some of the costly nonsense this admistration is trying to pass through into law.
There the liberals go again. Blame the black particles!
'Sluggish' jet streams linked to quiet Sun I first thought they were describing current weather in the US.
Nanoparticles make 'self-erasing' images
FReepmailFReepmail me if you want on or off my health and science ping list.
From the article:
“There is large scientific agreement that human made emissions of CO2 and other gasses give global warming.”
Here’s an article saying the opposite:
http://www.gazette.com/common/printer/view.php?db=colgazette&id=56674
Excerpts:
> Expect “climate change” to become more and more the catch phrase as it becomes more clear the planet isn’t warming. The evidence is becoming overwhelming: The National Oceanic and Atmospheric Administration found that snow cover in January was the most extensive ever recorded in Eurasia; NOAA found that temperatures in the tropical troposphere dipped to their lowest levels in 30 years in March; the Bering Strait ice cover in march was higher than ever recorded, while Antarctic sea ice cover was 30 percent above normal.
And
> In the 1970s, those who wanted to tax Americans to control the climate warned of a looming ice age. When temperatures rose, they changed their tune and warned of global warming. Now, as the temperature drops, they warn of “climate change.” Be skeptical.
Aerosols like sulfur, nitrate, and organic carbon are formed in the atmosphere and cause global cooling. Thereby they contribute to mask parts of the human induced global warming.IOW, there's no evidence of global warming, but that's because of humans too. Liars, demagogues, grifters, crooks, frauds! Thanks neverdem.
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I posted that one too.
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