Global dimming masks the effect of global warming

Plus, there's the absence of SNU, which may indicate that the sun is in a cooling phase.

My guess is storms, forest fires, earthquakes, tidal waves, and volcanos add about 100 times more particulates to the atmosphere than humans. Black particulates are heated by the sun, and reradiate longer wave lengths of infrared photons, most of which are absorbed by green house gasses, while the surface is shaded slightly. The atmosphere above one? mile altitude is warmed. Air circulation caries some of this warmer air to the polar region where a great down draft is typical. Thus the polar regions are warmer. Surface air moves away from the poles on the average thus the temperate zones are not cooled as much by the not so cold polar air.
Rather rare white and pastel particulates reflect some of the sun's energy back into space thus cooling tropic regions, as well as Arctic and temperate regions. Please comment, refute and/or embellish. Neil

During the above-mentioned TV programme it was stated, according to the work of an English scientist working in Israel, that sunlight falling on the surface of the earth had decreased by 22% since the 1950s.
We know that the sun has not decreased in intensity, so this effect is presumed due to the dimming phenomenon.
It may be that volcano particulates (Mt St Helens?) and forest fires have something to do with it; although much forest burning is generated by man these days, we hear. More likely is the burning of fossil fuels, according to the programme.

I cannot comment on the movement of air masses; hopefully someone else can.

A volcano erupting (major eruption) puts more particulate in the air than man has put into the air in total, forever. Sounds like the program you watched had a bit of an agenda.

I thought for sure you meant people were becoming so dim they couldn't see what's going on... :wink:

Now THAT's funny!

A 22% reduction in the solar energy impinging on the earth would have unmistakable immediate effects on climate. This has not occurred. I believe you are dealing with selective reporting of data and careful word choice designed to create a dramatic effect on the TV audience.

The earth is over 5 billion years old, has slowly evolved an oxygen rich atmosphere and endured numerous ice ages. As others have already noted, the actions of volcanoes can and have repeatedly dwarfed any effect humans have on airborne particulate, as well as SOX and other pollutants.

The sky is not falling in.

Well, I am putting the view advanced in the programme, that there is a measured and verified (by an independent method) 22% reduction in solar intensity reaching Earth. Some work was done in Israel, some in Germany, some in Australia, and all corroborate this.
The "agenda" is the future of the planet. The "counter-agenda", which seems to be largely an official American view, is that nothing much should change, we have no need to worry, and everything will probably be all right in the end.

The agenda is MONEY. If there's no crisis, there's no research money. If there's no crisis, the UN doesn't get money from taxing carbon. I don't necessarily have a problem believing that global warming can happen. However, the current "crisis" comes from the results from a mathematical model, which necessarily relies on the suppositions of those who designed the model. Climate is extraordinarily complex and a model, with our current computing power, cannot account for all of the variables - the model we have now indicates we should be cautious but, given the nature of the model, should not incite panic.

If global warming is being mitigated by atmospheric pollution, should there be a tax credit for polluting?

Well, my own no doubt simplistic view goes something like this:
We know glaciers are retreating uphill at a rate of knots, and that the ice cap is vanishing off Greenland and off Antarctica, a phenomenon new to us in recorded history.
We also know there is an unprecedented buildup of greenhouse gases in the atmosphere, principally carbon dioxide at the moment.
This theory offers a warning that the full effect of the atmospheric change is not being felt. It suggests that the warming (which critics say is moderate) would be ten times as much without the dimming effect.
I am suggestion these findings are worthy of the most serious attention, because if the forecasts arising from this are right, New York and London could be largely underwater in less than 100 years.
And Roger is right, until we know more about this, apparently the worst thing we could do at the moment is try to reduce atmospheric pollution. Go out tomorrow and burn a tree, maybe.

Your view is simplistic. Some glaciers are retreating, others are growing. Some sections of the Antartic ice cap are shrinking: others are growing fast. The estimates of actual warming are well below what might inundate New York. However coastlines have been eroding for centuries - (intersting story about Caesar;s landing sites in Britain aas they are now and as reported almost two millenia ago) , and cities on rivers are usually found stacked on top of earlier settlements - what happened??.

The human and economic cost of a curtailment of carbon emissions sufficient to significantly alter the greenhouse gas situation woulf far exceed the cost of doing nothing at all - with current technologies.

For those still interested in such curtailment, the most effective remedy by far would be a massive increase in the use of nuclear power to generate both electrical energy and to process synthetic fuels for transportation applications. Odd that most proponents of measures to curtail global warming are opposed to that.

George, I wish you could see the prog itself. All the points you raised were dealt with there. And all I am doing here, is highlighting it, for I admit I am no expert. I read widely enough to say however, that I fear you are wrong about the antarctic ice.

http://www.ananova.com/news/story/sm_838236.html?menu=news.scienceanddiscovery

And "the estimates" you refer to- that is the whole point, isn't it. It is "the estimates", especially those financed by industrial conglomerates, which are questioned.

McTag,

I will try to find out something about the issue. I do know that the chief manmade sources of airborne particulate are (1) Diesel engine exhaust gases, and (2) Inefficient burning of low quality coal and wood in, mostly primitive, low-pressure combustion applications such as cooking and heating. The second factor is larger than the first, and the well-known "brown cloud" over southern Africa and Asia is a result of it. There are large natural sources as well, volcanism being the most prominent (this one can easily dwarf human sources); forest fires also do their part..

There is so much misinformation afoot on this subject, and the public debate on it and related issues is so dominated by zealots who apparently wish to return to a sweet bucolic age (that in truth never existed), that I have become perhaps too skeptical about yet another doomsday scenario.

The earth is very old. Its climate and atmosphere have never been in a state of equilibrium: the geologic record demonstrates numerous ice ages; even tree ring data confirms substantial climactic variation, even during recorded human history. We know the reasons for only some of this (mostly an approximately 11 year cycle of solar activity, and recently emerging information about ocean currents and related energy transport phenomena), but lack a comprehensive understanding of most of it. It strikes me as highly presumptuous to suppose that we could significantly alter a phenomenon whose variations we are only beginning to understand.

The correlation between public reactions to risk and the actual risk itself is generally very poor. This is particularly true with respect to extremely remote, but horrific possibilities. We tend to react to them well out of proportion to the real risk they present while dulling our perceptions of many larger, but ubiquitous risks, which we have long since ceased to notice.

I run an Environmental company. Last year we did the risk assessment for the government-mandated cleanup of PCBs in the sediment of the Hudson River in New York. The sediments are fairly well encapsulated and the PCBs are leeching out at a fairly low rate, and slowly breaking down into harmless constituents. The cleanup will raise the levels if PCBs in the river for the next 40 years after which they will be significantly reduced. $2 billion will be spent in the cleanup. What is the public benefit? PBCs are a suspected carcinogen. The risk of drinking Hudson River water if the cleanup is not done are about equal to the risks of eating two pieces of toast a week. I haven't yet seen a public campaign against toast eaters. The government agency is happy because the fines and penalties will pay for their salaries.

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True, but the actual numbers may surprise you. CO2 is abou 5% of total green house gases. Water vapor actually is the majority of the rest of it. Of that 5%, our contribution is 6%. So, we can jump through all types of hoops to reduce our 6% of the 5% - let's say we reduce our contribution by 50%. We will have just made a 0.15% change in the total greenhouse gases. Do we honestly think that will change the climate of the planet? Perhaps we are giving ourselves way too much credit.

To debate these issues would be beyond me (although I know water vapour is not a greenhouse gas) but it is also a fact that methane locked in sea sediments in the Arctic and in the permafrost Siberian regions will begin to be released if average temperatures rise a few degrees more. This would be far more damaging than the CO2 is at the moment, and would markedly accelerate change.
Also, in the Royal Society Lecture TV programme broadcast here at Christmastime it was stated that a sustainable level of CO2 emissions per individual is around 2.5 ton per annum. In North America the actual figure is around 40 tons.
It is a very serious problem. Most science indicates that we are not living in a sustainable way, and the debate seems mainly to be about the rate of change.

I saw the programme too McTag and agree that the scientific base seemed sound - research on pan evaporation and statistics over long decades with a dramatic and well documented change in recent times.

As a non-scientist I can't back up the arguement with anything constructive but it certainly worried me.

with the speed and timescale it certainly needs urgent investigation.

(

Please don't be silly. Of course it is. Here's a Department of Energy link for you. It would be good if we could at least discuss from a basis of fact.

DOE link

What is sustainable? Certainly not the earth. In a few billion years the sun, having exhausted the lightest elements in its thermonuclear engine, will swell up, become a red giant and swallow all the inner planets. Numerical experiments with their orbital mechanics indicate that chaotic excursions in the planetary orbits of our own solar system are a real possibility in the next millions of years. Asteroid impacts sufficient to wipe out the species are a finite possibility, and evidence of similar such impacts in the past abounds. There are lots of 'end of it all' scenarios, and the warming one doesn't really make the cut in the time required to do the damage.

Did the program also cite the per capita CO2 emissions in Europe? I can't verify the 40 ton figure for North America (by the way those pesky Canadians consume a good deal more energy per individual than we do), but wonder what is the corresponding figure for Europe? Presumably it is greater than 25 tons per individual, or more than ten times the "sustainable" level. Do you believe that is a significant or meaningful difference? If sustainability is the goal, then CO2 emissions will have to be reduced to less than a tenth of their current levels in developed countries, (By the way India and China are very rapidly closing the gap on us.) Do you believe that we can sustain the population of the planet with that low level of emissions? I don't.

Oceanic methane bubbles do occur in temperate climates. Methane is about 26 times as potent a greenhouse gas (per unit of mass) as CO2. I hope all those gas lines from Russia that have enabled Europe to cease burning its low heating value, high sulfur brown coal don't leak much (sadly they do). Humans, of course, in their respiration and flatulence are a constant direct source of greenhouse gases. Perhaps old Malthus was right after all.

I would be more impressed with such analyses (and TV programs) if they would at least briefly reach beyond the dramatization of the obvious and superficial aspects of all this and examine the tradeoffs and the consequences of the actions they so blithely imply are required. This would substantially lessen their dramatic impact.