Global Dimming

[arkain101]

Oh and another thing.

How does weather get created? We all know it very well has to do with imbalence in the atmosphere.

If there is high pressure here, and low pressure there, the (whats that principle/law called again?) pressures will equalize, creating, weather.

The more intense you can create unbalance, the greater the movement and change in weather one can create.

So if we picture earth with a hypothetical filter around it that causes sunlight to penitrate into it with complete equalness to reduce pressure differences, the weather we can theoretcially assume will remain calm because it is more in equalibrium.

If we beging to tear large holes in this filter, and also put solid blocking patches on this filter. Sun light will reach some spots intensely, some spots not at all, and some spots regularly. This will cause many different pressure differences in the atmosphere. Wind, turbulance, etc.

Now we apply this simple logical thinking to a cristine pure atmosphere, versus a weakening ozone atmosphere with areas that are high in heat containing, and others high in heat reflection capabilities. Weather will get more motivated to react..

What say you?

[Turtle]

Originally Posted by Cedars

I think this needs to be retested several times before it can be given credence. To see this much of a temp change based on a few days of commerical flight groundings in the USA leads me to be skeptical of the actual cause of this warming.

To clarify again, contrails account for very little (about 2% they said) of reflected sunlight, the rest coming from particulate pair pollution. Evidence of the 'global dimming' effect is actually some 30 years old, coming by way of evaporation tray readings. This is a measurement I only first learned of from this show on PBS.
A circular tray of water is left exposed to the elements, and each day the keeper measures & records how much water they must add to bring the tray back to its original level. The data provide a means of measuring the rate of evaporation.
When record keepers noticed this rate falling, i.e. less evaporation, they went looking for the cause. They looked at wind & humidity levels, but in lab experiments this did not correlate to the actual decline. The answer they found lay in less sunlight, moreover experiments showed that photons striking the water account for the majority of evaporation.
So again, the existence of global dimming is well established. What remains unknown is the amount & rate of the dimming & especially the effect these values have on slowing the global warming.

[Cedars]

Originally Posted by Turtle

To clarify again, contrails account for very little (about 2% they said) of reflected sunlight, the rest coming from particulate pair pollution. Evidence of the 'global dimming' effect is actually some 30 years old, coming by way of evaporation tray readings. This is a measurement I only first learned of from this show on PBS.
A circular tray of water is left exposed to the elements, and each day the keeper measures & records how much water they must add to bring the tray back to its original level. The data provide a means of measuring the rate of evaporation.
When record keepers noticed this rate falling, i.e. less evaporation, they went looking for the cause. They looked at wind & humidity levels, but in lab experiments this did not correlate to the actual decline. The answer they found lay in less sunlight, moreover experiments showed that photons striking the water account for the majority of evaporation.
So again, the existence of global dimming is well established. What remains unknown is the amount & rate of the dimming & especially the effect these values have on slowing the global warming.

When I was very young, my neighbor who owned a farm (I mentioned him in the birding thread) told me the skys were not as blue as when he was younger. While I listened to him talk of seeing nearly violet skys, the blue was so deep sometimes, I wondered if it was failing vision that accounted for this observation on his part. I will say that I too think the sky is not as blue now as when I grew up and aging eyes is not the sole cause for my observations.

But to see that much of a temp change from the grounding of planes alone leaves me skeptical of those particular observations.

[Turtle]

Originally Posted by Cedars

I will say that I too think the sky is not as blue now as when I grew up and aging eyes is not the sole cause for my observations.

But to see that much of a temp change from the grounding of planes alone leaves me skeptical of those particular observations.

Apparently the scientists who noticed it expressed their skepticism with surprise. While no one is suggesting stopping all flights again, it has prompted a host of other means and experiments to further examine the phenomenon of global dimming in general.
I don't recall the blueness of the sky from childhood; interesting observation though.

[Michaelangelica]

Originally Posted by arkain101

Oh and another thing.
How does weather get created?
What say you?

I vaguely heard on a BBC Discovery programme that plants exude a protein.
This protein causes water vapour to condense around it and thus create clouds.
Apparently, in the Amazon, you can test the rain for particular proteins to find out where it has come from.
I only half-heard the programme anyone else know about this?

[Turtle]

Originally Posted by Michaelangelica

I vaguely heard on a BBC Discovery programme that plants exude a protein.
This protein causes water vapour to condense around it and thus create clouds.
Apparently, in the Amazon, you can test the rain for particular proteins to find out where it has come from.
I only half-heard the programme anyone else know about this?

I haven't read this whole transcript from BBC yet to see if it has the protein reference, however I found it as the #2 Google hit when I searched "pan evaporation rate".
Thanks again Micha.
http://www.bbc.co.uk/sn/tvradio/prog...ng_trans.shtml

PS

Originally Posted by BBC

Sea salt and natural sulphur compounds emitted by plankton are also very important for cloud formation.

[Michaelangelica]

Latest on global dimming from the BBC
http://www.bbc.co.uk/sn/tvradio/prog..._summary.shtml

I wonder if all the world's black roads were painted white, would this reflect enough sunlight to make a difference either-way?

I wonder if every floor, of every ofiice-block, of every city, were packed with indoor plants would this effect CO2 levels or reduce the mini-particles floating in the air?

[InfiniteNow]

Originally Posted by Michaelangelica

I wonder if all the world's black roads were painted white, would this reflect enough sunlight to make a difference either-way?

I imagine some. Isn't this called albumen or something?

I wonder if every floor, of every ofiice-block, of every city, were packed with indoor plants would this effect CO2 levels or reduce the mini-particles floating in the air?

And roofs and everything with outdoor plants too... What if we put some sort of requirement in place where by vehicles (jets included!) have a vegetation filter between the engine and the exhaust?

Maybe peat land vegetation, but then we'd have more methane... Anyway, we could then have a filter replacement of the vegetation with each petroleum refill. Just like chaning an air or oil filter, but on the exhaust end. And the filter is vegetation which helps scrub the carbon.

"At Sonny's Quick'n'Full, we've got the peat to assist in carbon defeat. Also, with each fillup, get a free wheat grass juice..."

Has this been discussed somewhere? Would it fail immediately? Have merit?

Fire away.

[pgrmdave]

Isn't this called albumen or something?

Albedo, I believe. (If I remember my SimEarth correctly).

[InfiniteNow]

Originally Posted by pgrmdave

Albedo, I believe. (If I remember my SimEarth correctly).

Yep... hit the nail on the head. Thanks. Was having a senior moment.