OT: Horizon - Global Dimming/Warming

Yes, so unknowingly we have done two things to the environment that have mostly counteracted each other. If we continue to cut pollution, and thereby reduce the cooling effect, we must cut greenhouse gasses too or face the consequences over the next few decades.

Wasn't there climate change before man came along? What caused all those ice ages thousands of years ago? ISTR 20 years or so ago the "experts" were threatening us with another ice age.................

Dave

1983 series 3 SWB petrol (proudly contributing to global warming thanks to poor fuel consumption)

Hi Alan

I watched it - with a growing sense of apprehenion. The nuclear fision scenario seems to offer the only way out unless we can get the fusion problems licked. I guess that if we don't get sorted old Gaia will do it for us!

Too many wanting too much.

Perhaps we should persuade Gdubya to pre-emptively nuke China to buy us a decade or two of time! Then there's India to think about. They can't all have air-conditioning, fridges, freezers and family cars or we'll all be bolloxed!

Tough decisions will be required before 2050. I worry for my grand- children & their kids.

Dave J

On or around Sat, 15 Jan 2005 01:10:34 GMT, Jacko enlightened us thusly:

bloody bloke doing the narrative drove me nuts. But a worrying conclusion, even so. Perhaps I should retune the TDi to make black smoke, and help avoid global warming by creating more dimming... nah, better not.

indeed. The world would be much better off with about 40% of its current population, the trouble is, deciding which 60% to get rid of.

much sooner than that, I suspect, if we stand a real chance of stopping it. What we really need to do is get rid of head-in-the-sand politicos whose only interest is their own career or making a fast buck out of oil.

As an example: many millions of people commute unnecessarily to work every day. Communications now really are up to having people working from home.

On or around Fri, 14 Jan 2005 23:27:08 -0000, "David Bexhall" enlightened us thusly:

yes, there was. But it took 10,000 years or so to do the amount of change we've achieved in 100.

Just seen this on repeat - scary!

The theory behind the program, that more sunlight is reflected, due to (sulphate) aerosols is proven false.

As you may know, we have some satellites flowing around out of the atmosphere, which measure reflected sunlight (SW reflection) and heat (LW emission) from below.

For the (sub)tropics, in the period 1985-2001 the amount of sunlight reflected by clouds reduced with ~2 W/m2. (see:

confirmed for the 30N-30S (sub)tropics in ) In the same period, there was a loss of cloud cover, both in the tropics and sub tropics (and even up to 60N-60S).

If there is global dimming at the surface, the only explanation possible is that more sunlight is retained in the atmosphere. Which is (only) possible with (dark brown and black) soot particulate.

If soot particulate is to blame, then a reduction of them would have a cooling effect, not a warming effect!

See also the amount of reflected sunlight from earth on the moon ("eartshine"), which parallels the "global dimming" trend, while it should have opposite trends, at:

Ferdinand

I haven't seen it, but I have noticed Horizons decline from a factual documentary into some kind of sensationalist scaremonger. They rarely tackle current issues anymore, preferring to look at thinks that 'could' happen & look good on a computer simulation etc.

Don't really watch it much these days.

Nige

-- Subaru WRX (The Bitch)

Series 3 Landrover 88" (Albert)

"If you tolerate this then your children will be next"

Which is what I understood the program to have expalined, it was the soot and general pollution in the atmosphere actually cooling things down by absorbing/reflecting sunlight by creating clouds that are more dense than those naturally created and the greenhouse gases that were adding to global warming.

Now that we're on an enviromental crusade to reduce all the soot and pollutants in the atmosphere we're accelerating global warming as we haven't done enough to also reduce emmissions of greenhouse gasses.

As I understood the Horizon program (and I'm no scientist) you've basically described the same situation occuring but you theory of where the loss in sulight has gone differs slightly but with the same outcome.

Whenever I watch these I always take them with a pinch of salt, as at one time the most intelligent people on the planet told us the Earth was flat. And a large proportion of the scientific results are conjecture, it still makes an interesting program though.

I miss QED though.....wish they'd bring that back.

Alan M.

The argument that nature is actually to blame for the exponential increase in atmospheric carbon has been the excuse clung on to by anyone who either has a vested interest in the profitability of carbon emitting factors or on a much lower (sic) level those 'good ol' boys often know by the name if 'Bubba' in the USA ,who simply seek to justify their not subscribing to the solution i.e., changing to a lower polluting lifestyle.

However such self serving and spurious arguments, though ironically kamikaze in effect, are easily rebutted by simple reference to the facts.

WE KNOW THAT THE MASSIVE INCREASE IN ATMOSPHERIC CARBON IS MAN MADE BECAUSE THE ISOTOPES REVEAL THE DIFFERENCE BETWEEN MAN MADE AND NATURAL PARTICLES.

Or Proof Positive as they say