The Earth's albedo (reflectance) to the Sun's energy is around 34% as indicated in the first presentation. Whether or not the atmosphere acts as a blanket, the Earth would have a harder time becoming dangerously hot if less of the Sun's energy were absorbed by the Earth. Imagine if there were some way that we might somehow increase that albedo a little, maybe up to 36%. The effect (as calculable by the equations in the first presentation) would be a net reduction of incoming energy from 66% to 64%, a significant amount of energy (around 4 * 1015 watts, around 8,000 times as much energy as ALL the electricity used in the United States!). (That much change would result in a reduction of the Earth's equilibrium temperature by around 3.9ºF., as can be confirmed with the equations of the first page of this presentation.) Could something like this be done? That amount of change might not be enough to really eliminate all the problems, but it might enable the persistent existence of plants and animals and people on Earth.
The most logical possibility that occurred to me is regarding the fact that our Government says there are around 8.5 million miles of roads in the US, with the majority of them being paved with asphalt. There are also an impressive amount of area of parking lots which are all asphalt, particularly in and near cities, as well as a surprisingly large number of flat-roofed buildings that have asphalt-based roofs.
This all indicates that there are well over 100,000 square miles of area of the United States that is currently covered by Asphalt, in pavement in highways and roads, in pavement in parking lots, in the Asphalt roofing on countless flat-roofed buildings, etc. (The entire country has around 36 times that area.) Asphalt happens to be black and it has an extremely high absorbtivity and emissivity of solar energy, generally described as being around 0.95 or 95%. So, imagine if all that asphalt were somehow changed in color to extremely reflective white, for example. What effect would that have? The area we are talking about is only around 1/2000 of the surface area of the Earth, so it figures that the effect might be limited. We can convert the 100,000 square miles into square meters of area, and multiply it by the 893 watts of solar energy coming in per square meter, to get a value of around 2.3 * 1014 watts, as being the maximum incoming radiation energy from the Sun. But since the Earth rotates, and is spherical, this actual AVERAGE energy rate is around 6 * 1013 watts, which ACTUALLY hits the Asphalt surfaces of the United States.
For comparison, this is around 120 times the TOTAL amount of electricity energy that we use up in the US! A significant amount of energy.
And if we could change the color of all that asphalt so that it reflects maybe 85% of that incoming solar energy rather than the 5% it currently reflects, that simple action of changing the color of all that asphalt could eliminate around 5 * 1013 watts of (heat) energy from BEING ABSORBED and even entering our planet's ecosystem! The fact that the light is REFLECTED means it stays in the same wavelengths, including visible and ultraviolet, which could then generally pass easily OUTWARD through our atmosphere, without having any global warming effects. A really good thing!
And being the removal of around 100 times the energy of all the electricity we use up (which all becomes heat after we use it), or around 50 times the amount of heat energy that electric powerplants throw off in the process of making that electricity, this would certainly be a wonderful step in the right direction.
Counteracting the massive energy dumping into the atmosphere of electric powerplants and much more, would be a very wonderful accomplishment!
How hard would it be to do such a thing? Maybe fairly easy! Consider the traffic markings on the highways! White lines and yellow lines are EVERYWHERE! True, some are merely painted on, but many are heat-melted (thermoplastic) into becoming part of the roadway. So imagine that instead of a four-inch wide line, the white line now at the edge of every roadway was made far wider, to cover the entire surface of the highway. (Maybe the line markings could then be black or some contrasting color.) The materials used for those lines have already been fully tested for not making the roads too slippery or wearing out too quickly, or otherwise detrimentally affecting the asphalt surface. So such a change could be done virtually next week! The plastic nature of the coating material would even reduce moisture penetration into the asphalt, probably lengthening the life of the road materials! A company in India manufactures a material they call ROMAC, which comes in bags and is heated to around 200ºC and then applied in any of several standard methods, to a thickness of around 2.5 mm (0.1 inch). That would be it!
We should certainly do such things, but we clearly need to do far more as well. This is a good indication of how huge the problem is! For us to change the color of EVERY highway and road in America, and every parking lot, and every flat rooftop, in having the benefit around a hundred times better than the total amount of all energy dumped into the atmosphere related to our usage of electricity, STILL only has such a miniscule effect in reducing the equilibrium temperature. It is amazing.
However, if we did this, and changed the color of all of our highways and parking lots and rooftops, maybe other countries might follow and do the same. And maybe people smarter than me will then see other and better ways to reflect more sunlight. Or other creative ways of giving us a fighting chance of survival as a species.
The Earth's Rotation as a Source for Energy
Waste Nuclear Power For Making Electricity And Heat?
The Physics of Efficiency In Electric Power Plants
Individual Ways of Reducing Your Energy Usage
Methods of Storing Energy for Later
How Much Energy Comes From the Sun? And Why is there Global Warming?
How does the Sun create so much energy?
Inventions Which Might Help Deal With Coming Energy Catastrophes
An Invention to Efficiently Make Electricity from Solar
Enormous Heating of the Atmosphere by the Alaska Pipeline
Air Conditioning without Huge Electric Bills and without Freon
A Method of Storing Summer Heat to (Nearly) Entirely Heat a House all Winter
An Extremely Highly-Efficient (and Fast, 200.0 mph) Transportation System for People and Products
The Sophisticated Woodstove I Invented in 1973
The Physics of Wood as a Heating Fuel
Why is the North Pole Heating Faster than the rest of the Earth?
A Possible way to greatly reduce Aerodynamic Drag of Airplanes
( http://mb-soft.com/public/index.html )
C Johnson, Physicist, Physics Degree from Univ of Chicago