[lyner]

Ops, I notice that I've misquoted something [:I] Is that stuff about the

It is well known as black body radiation

true?

Yes, I think you are.
The bit about re radiation is also true but, because human skin is only at 300K, there may be less radiated than absorbed from the sun. There is no reason to assume the emissivity of black skin is different from that of white skin for infra red. The pigment may well not be an ideal 'black body'.

[NobodySavedMe (OP)]

Ops, I notice that I've misquoted something [:I] Is that stuff about the

It is well known as black body radiation

true?

Yes, I think you are.
The bit about re radiation is also true but, because human skin is only at 300K, there may be less radiated than absorbed from the sun. There is no reason to assume the emissivity of black skin is different from that of white skin for infra red. The pigment may well not be an ideal 'black body'.

That is incorrect.

In any case the power bill and consumption can be reduced by at up to 50% if roads were white as reflected light will reduce the need for higher powers and also the spacing could be increased between lamps.

No need to paint them at all.

All you have to to is make the sale of black tyres illegal and mandate all tyres produced must be white.Hence the continual wear and tear of white tyres will gradually make the roads white.

[Chemistry4me]

What about the cost of making white tires? For all we know, they could decompose and release carbon dioxide and methane gas...  []

[turnipsock]

I'm going back to driving with my night vision goggles and not turning my lights on.

[Chemistry4me]

All you have to to is make the sale of black tyres illegal

What about black/dark coloured vehicles, you going to distroy them too?

[techmind]

A similar line of thinking is that if we all put several square metres of (dark-coloured) solar panel on our roofs (whether simple thermal/hot-water, or photovoltaic) "for the environment" we'd appreciably increase the solar-absorbtion of the planet.
Food for thought.

[lyner]

NSM

That is incorrect.

Which bit's incorrect?

[lyner]

A similar line of thinking is that if we all put several square metres of (dark-coloured) solar panel on our roofs (whether simple thermal/hot-water, or photovoltaic) "for the environment" we'd appreciably increase the solar-absorbtion of the planet.
Food for thought.

Not really. If you made use of that particular received power, you would not need to produce it by burning fuels etc.
White roofs would have a useful function in all circumstances where you didn't actually 'need' the heat.
Plus - whitewashing the desert would be even better value.

[Karsten]

I just today read an article (Times I believe) about planting crops that reflect sunlight more efficiently. While they talked a whole lot about genetic engineering, this approach may cover more surface area than the white roads we still would need to build. While corn in Iowa? On the other hand, growing hundreds and hundreds of square miles of reflecting plants makes only sense if we do not fertilize them with products that require the use of fossil fuels.

And could any of this actually counter the disappearance of the huge areas of highly reflective ice?

[Karsten]

Not really. If you made use of that particular received power, you would not need to produce it by burning fuels etc.

I often wonder whether solar cells (photovoltaic that is) actually ever create as much energy as it requires to make them. Do you know?

[lyner]

It used to be the case that PV cells produced less energy than their manufacture  used but I think it's better than that now.

[paul.fr]

All you have to to is make the sale of black tyres illegal and mandate all tyres produced must be white.Hence the continual wear and tear of white tyres will gradually make the roads white.

do you think the residue left by the "wear and tear" will just sit there on the road? I think you will find the wind just may, blow it away.

I just today read an article (Times I believe) about planting crops that reflect sunlight more efficiently. While they talked a whole lot about genetic engineering, this approach may cover more surface area than the white roads we still would need to build. While corn in Iowa? On the other hand, growing hundreds and hundreds of square miles of reflecting plants makes only sense if we do not fertilize them with products that require the use of fossil fuels.

The other problem is, the crops also add to the moisture in the air.

[Chemistry4me]

But more crops will mean less carbon dioxide will it not?

[Karsten]

I just noticed:

It should say WHITE corn in Iowa, not "while corn in Iowa". I hope it did not make sense before because it sure was not meant to make sense that way.

[Karsten]

But more crops will mean less carbon dioxide will it not?

I guess that depends on how much CO2 you add while making the synthetic fertilizers from fossil fuels.

[Chemistry4me]

But more crops will mean less carbon dioxide will it not?

I guess that depends on how much CO2 you add while making the synthetic fertilizers from fossil fuels.

Why?

[NobodySavedMe (OP)]

All you have to to is make the sale of black tyres illegal and mandate all tyres produced must be white.Hence the continual wear and tear of white tyres will gradually make the roads white.
[/quoteq

do you think the residue left by the "wear and tear" will just sit there on the road? I think you will find the wind just may, blow it away.

I just today read an article (Times I believe) about planting crops that reflect sunlight more efficiently. While they talked a whole lot about genetic engineering, this approach may cover more surface area than the white roads we still would need to build. While corn in Iowa? On the other hand, growing hundreds and hundreds of square miles of reflecting plants makes only sense if we do not fertilize them with products that require the use of fossil fuels.

Asphalt is porous.

just like chewing cum the white tyre particles will be embedded in it.

also remember it will constantly renewed by white tyres passing over.

I suggest you contact your government official so that he can get it started.

Already incandescent bulbs are being outlawed, let us outlaw black tyres now.

you only need to add a dye to make black tyres look white.

I believe i have seen white tyres somewhere already...possibly antique cars.

[Don_1]

[just like chewing cum.............

Never have, never will.

FOG

[Bored chemist]

Whoa!  [] So white coloured objects can't reflect IR, I did not know that... []

I don't think anyone said that.
I did point out that white objects will reflect visible light which will then leave the earth rather than becomiing trapped and heating it.

[Chemistry4me]

So is it true or not?