Very white paint

Joined
Nov 6, 2004
Messages
912
For all the tree huggers out there, wouldn't reflective paint just reflect solar radiation back into the atmosphere and heat it up?
So, no. Sorry, y'all probably didn't realize you were casting "Summon Geology Professor and Research Scientist" did you? ;)

The basic physics of this have been know since approximately the 1850-1890's (so, no blaming Al Gore dammnit, that's really boring at this point)

Approximately 70% of the sun's energy currently is absorbed by the earth at some level.
30% is reflected as essentially the same energy back out into space (on average, there's a bunch of variability based on Location, ground cover, etc.)
This is the chunk that would get increased by this paint. Even if 31% got reflected, this would result in a pretty impressive amount of global cooling. Btw, 1% increase is WAY overstating the effect of this paint, unless literally every building on earth was coated in it. Even during Glacial maximum's (Ice Ages) the global average reflectivity only increased by a few % points, due to the ice sheets covering big chunks of N. America and Eurasia.

The drop in energy use would be the biggest impact to global temperatures, and thus, anthropogenic global warming.

Of 70% that reaches the earth's surface, most of it is absorbed by the ground, increasing it's temperature, and is then re-radiated as heat. The various greenhouse gasses (Water Vapor, CO2, CH4, O2/O3, CFC's mainly) absorb, and re-radiate about 1/2 back to earth as heat. This is the Greenhouse effect. Note: without the greenhouse effect, Earth's average temperature would be roughly -15C, so YAAAY Greenhouse)

The whole anthropogenic global warming thing is basically, if there are more of the Water Vapor, CO2, CH4, O2/O3, then more of that energy get's re-radiated back to earth, which increases the temperature.

BTW, Water Vapor is a hugely important greenhouse gas, but it's also very much self-limiting. Too much water vapor, clouds form, which increases the amount of energy that is bounced into space. Global average reflectivity varies between 30% and 35% based mainly on northern Hemisphere seasonal cycles, because such a large percentage of the northern hemisphere is land, instead of ocean when compared to the southern hemisphere.

O2/O3 (Oxygen/Ozone), have a pretty small impact, and have pretty freaking stable concentrations at 21% for O2 and "damn near nothing" for O3 (except in the lower stratsophere, where the ozone layer is, and ozone is STILL only like 30 parts-per-billion!) They are also, more-or-less not affected by global warming processes.
CFC's are completely man-made, but are trace, the biggest effect they have is destruction of Ozone, with a single molecule of CFC being capable of destroying 10's of thousands of ozone molecules, because the CFC acts as a catalyst.

CH4 is hugely important, but also 'relatively' short lived in the atmosphere, being used in a bajillion biological processes, so it's average time in the atmosphere is about 10 years. And, the amounts are measured in parts-per-trillion, so there's not a lot around. Which also means it's easy to increase it, in the short term. We have tripled the pre-industrial values of CH4, but, because of the short life in the atmosphere, we've kind of already "stablized" CH4 without even really changing stuff.

CO2 is hugely important, is only used in basically two biological process (photosynthesis and shell-forming organisms), and it's measured in parts-per-million ( Today is 417 ppm, 'pre-industrial' is about 280 ppm, so we've already increased it by about 50% from pre-industrial levels.) Also, it's residence time in the atmosphere is over 100 years, so once it's up there, it's there for a while.

Really anthropogenic global warming is all about how much CO2 and CH4 we have added to the atmosphere, and how much that is changing the amount of heat caught (on the way out) by the atmosphere, and re-radiated back to hearth.

BTW, the really freaking scary part of anthropogenic climate change is
1) The rate of change. The fastest the earth has warmed "naturally" is the end of an Ice Age, which is ~5 degrees C warming in ~5000 years. So, 1 degree per 1000 years. Global temps have increased over 1C since pre-industrial levels, in ~150 years.
2) And, IMO, this is the scary part. There is approximately 50-100 years of "lag" in the climate system (it has a LOT of inertia). Which means, the warming we have already experienced is from atmospheric changes between say, 1920 and 1970 ish. And we have DOUBLED the amount of CO2 we have added to the atmosphere since 1970.

So, regardless of ANYTHING we do right now, we have already signed up for at least another 1C warming, which is enough to entirely destabilize the West Antarctic Ice Sheet (WAIS) and big chunks of Greenland Ice Sheet (GIS) based on modelling. Which, at the end of the day, is just a numerical 'best-guess' at how the climate system works, anyways, and also tend to understate the effects based on comparing old models to the last 30 years of actual measurements.
 
Last edited:
Joined
Nov 18, 2011
Messages
641
So, no. Sorry, y'all probably didn't realize you were casting "Summon Geology Professor and Research Scientist" did you? ;)

The basic physics of this have been know since approximately the 1850-1890's (so, no blaming Al Gore dammnit, that's really boring at this point)

Approximately 70% of the sun's energy currently is absorbed by the earth at some level.
30% is reflected as essentially the same energy back out into space (on average, there's a bunch of variability based on Location, ground cover, etc.)
This is the chunk that would get increased by this paint. Even if 31% got reflected, this would result in a pretty impressive amount of global cooling. Btw, 1% increase is WAY overstating the effect of this paint, unless literally every building on earth was coated in it. Even during Glacial maximum's (Ice Ages) the global average reflectivity only increased by a few % points, due to the ice sheets covering big chunks of N. America and Eurasia.

The drop in energy use would be the biggest impact to global temperatures, and thus, anthropogenic global warming.

Of 70% that reaches the earth's surface, most of it is absorbed by the ground, increasing it's temperature, and is then re-radiated as heat. The various greenhouse gasses (Water Vapor, CO2, CH4, O2/O3, CFC's mainly) absorb, and re-radiate about 1/2 back to earth as heat. This is the Greenhouse effect. Note: without the greenhouse effect, Earth's average temperature would be roughly -15C, so YAAAY Greenhouse)

The whole anthropogenic global warming thing is basically, if there are more of the Water Vapor, CO2, CH4, O2/O3, then more of that energy get's re-radiated back to earth, which increases the temperature.

BTW, Water Vapor is a hugely important greenhouse gas, but it's also very much self-limiting. Too much water vapor, clouds form, which increases the amount of energy that is bounced into space. Global average reflectivity varies between 30% and 35% based mainly on northern Hemisphere seasonal cycles, because such a large percentage of the northern hemisphere is land, instead of ocean when compared to the southern hemisphere.

O2/O3 (Oxygen/Ozone), have a pretty small impact, and have pretty freaking stable concentrations at 21% for O2 and "damn near nothing" for O3 (except in the lower stratsophere, where the ozone layer is, and ozone is STILL only like 30 parts-per-billion!) They are also, more-or-less not affected by global warming processes.
CFC's are completely man-made, but are trace, the biggest effect they have is destruction of Ozone, with a single molecule of CFC being capable of destroying 10's of thousands of ozone molecules, because the CFC acts as a catalyst.

CH4 is hugely important, but also 'relatively' short lived in the atmosphere, being used in a bajillion biological processes, so it's average time in the atmosphere is about 10 years. And, the amounts are measured in parts-per-trillion, so there's not a lot around. Which also means it's easy to increase it, in the short term. We have tripled the pre-industrial values of CH4, but, because of the short life in the atmosphere, we've kind of already "stablized" CH4 without even really changing stuff.

CO2 is hugely important, is only used in basically two biological process (photosynthesis and shell-forming organisms), and it's measured in parts-per-million ( Today is 417 ppm, 'pre-industrial' is about 280 ppm, so we've already increased it by about 50% from pre-industrial levels.) Also, it's residence time in the atmosphere is over 100 years, so once it's up there, it's there for a while.

Really anthropogenic global warming is all about how much CO2 and CH4 we have added to the atmosphere, and how much that is changing the amount of heat caught (on the way out) by the atmosphere, and re-radiated back to hearth.

BTW, the really freaking scary part of anthropogenic climate change is
1) The rate of change. The fastest the earth has warmed "naturally" is the end of an Ice Age, which is ~5 degrees C warming in ~5000 years. So, 1 degree per 1000 years. Global temps have increased over 1C since pre-industrial levels, in ~150 years.
2) And, IMO, this is the scary part. There is approximately 50-100 years of "lag" in the climate system (it has a LOT of inertia). Which means, the warming we have already experienced is from atmospheric changes between say, 1920 and 1970 ish. And we have DOUBLED the amount of CO2 we have added to the atmosphere since 1970.

So, regardless of ANYTHING we do right now, we have already signed up for at least another 1C warming, which is enough to entirely destabilize the West Antarctic Ice Sheet (WAIS) and big chunks of Greenland Ice Sheet (GIS) based on modelling. Which, at the end of the day, is just a numerical 'best-guess' at how the climate system works, anyways, and also tend to understate the effects based on comparing old models to the last 30 years of actual measurements.

::bites thumb::

Kuchiyose Jutsu! Zumino!
 
Last edited:

sfsuphysics

[H]F Junkie
Joined
Jan 14, 2007
Messages
14,739
Damn, I was just going to say something simple like the reason why visible light gets to the surface is because our atmosphere largely doesn't absorb visible light, so no reflecting back up doesn't do anything "bad". Not throw all of climate change theory at the guy :D
 

nilepez

[H]F Junkie
Joined
Jan 21, 2005
Messages
11,775
I think the main point is that this paint can reduce the temperature below ambient.
As a building covering, it would reduce cooling costs, but increase winter heating costs, so it seems kind of pointless to me in, except in the tropics.
But if a simple white painted device could condense water out of the air, dry places along the coast would have an alternative to desalination.
True, but there's much less light in the winter. When i lived in the NE it was often overcast in the winter. When i was in Belgium around XMAS, the sun didn't rise until almost 9am...and generally it was overcast.
But TBH, if other places would benefit more from Black, there's very black paints available.
 

sharknice

2[H]4U
Joined
Nov 12, 2012
Messages
2,409
So, no. Sorry, y'all probably didn't realize you were casting "Summon Geology Professor and Research Scientist" did you? ;)

The basic physics of this have been know since approximately the 1850-1890's (so, no blaming Al Gore dammnit, that's really boring at this point)

Approximately 70% of the sun's energy currently is absorbed by the earth at some level.
30% is reflected as essentially the same energy back out into space (on average, there's a bunch of variability based on Location, ground cover, etc.)
This is the chunk that would get increased by this paint. Even if 31% got reflected, this would result in a pretty impressive amount of global cooling. Btw, 1% increase is WAY overstating the effect of this paint, unless literally every building on earth was coated in it. Even during Glacial maximum's (Ice Ages) the global average reflectivity only increased by a few % points, due to the ice sheets covering big chunks of N. America and Eurasia.

The drop in energy use would be the biggest impact to global temperatures, and thus, anthropogenic global warming.

Of 70% that reaches the earth's surface, most of it is absorbed by the ground, increasing it's temperature, and is then re-radiated as heat. The various greenhouse gasses (Water Vapor, CO2, CH4, O2/O3, CFC's mainly) absorb, and re-radiate about 1/2 back to earth as heat. This is the Greenhouse effect. Note: without the greenhouse effect, Earth's average temperature would be roughly -15C, so YAAAY Greenhouse)

The whole anthropogenic global warming thing is basically, if there are more of the Water Vapor, CO2, CH4, O2/O3, then more of that energy get's re-radiated back to earth, which increases the temperature.

BTW, Water Vapor is a hugely important greenhouse gas, but it's also very much self-limiting. Too much water vapor, clouds form, which increases the amount of energy that is bounced into space. Global average reflectivity varies between 30% and 35% based mainly on northern Hemisphere seasonal cycles, because such a large percentage of the northern hemisphere is land, instead of ocean when compared to the southern hemisphere.

O2/O3 (Oxygen/Ozone), have a pretty small impact, and have pretty freaking stable concentrations at 21% for O2 and "damn near nothing" for O3 (except in the lower stratsophere, where the ozone layer is, and ozone is STILL only like 30 parts-per-billion!) They are also, more-or-less not affected by global warming processes.
CFC's are completely man-made, but are trace, the biggest effect they have is destruction of Ozone, with a single molecule of CFC being capable of destroying 10's of thousands of ozone molecules, because the CFC acts as a catalyst.

CH4 is hugely important, but also 'relatively' short lived in the atmosphere, being used in a bajillion biological processes, so it's average time in the atmosphere is about 10 years. And, the amounts are measured in parts-per-trillion, so there's not a lot around. Which also means it's easy to increase it, in the short term. We have tripled the pre-industrial values of CH4, but, because of the short life in the atmosphere, we've kind of already "stablized" CH4 without even really changing stuff.

CO2 is hugely important, is only used in basically two biological process (photosynthesis and shell-forming organisms), and it's measured in parts-per-million ( Today is 417 ppm, 'pre-industrial' is about 280 ppm, so we've already increased it by about 50% from pre-industrial levels.) Also, it's residence time in the atmosphere is over 100 years, so once it's up there, it's there for a while.

Really anthropogenic global warming is all about how much CO2 and CH4 we have added to the atmosphere, and how much that is changing the amount of heat caught (on the way out) by the atmosphere, and re-radiated back to hearth.

BTW, the really freaking scary part of anthropogenic climate change is
1) The rate of change. The fastest the earth has warmed "naturally" is the end of an Ice Age, which is ~5 degrees C warming in ~5000 years. So, 1 degree per 1000 years. Global temps have increased over 1C since pre-industrial levels, in ~150 years.
2) And, IMO, this is the scary part. There is approximately 50-100 years of "lag" in the climate system (it has a LOT of inertia). Which means, the warming we have already experienced is from atmospheric changes between say, 1920 and 1970 ish. And we have DOUBLED the amount of CO2 we have added to the atmosphere since 1970.

So, regardless of ANYTHING we do right now, we have already signed up for at least another 1C warming, which is enough to entirely destabilize the West Antarctic Ice Sheet (WAIS) and big chunks of Greenland Ice Sheet (GIS) based on modelling. Which, at the end of the day, is just a numerical 'best-guess' at how the climate system works, anyways, and also tend to understate the effects based on comparing old models to the last 30 years of actual measurements.

We also already have white paint. The article acts as if having 5% whiter paint is somehow going to solve global warming and provide energy free air conditioning as if the modern world wasn't already utilizing reflective surfaces.

Also if this is like any of the other specialized paints it will not hold up to outdoor elements.
 

revenant

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Joined
Apr 10, 2005
Messages
14,687
powder.jpg

Powder approves.
 
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