Global Warming, and How Much Solar Energy Comes from the Sun?

Energy rates are commonly described in either Btu/sq. ft./hour (English system) or Watts/sq. meter. We will discuss a number of different descriptions regarding solar energy.

The first and simplest answer is for the amount of solar energy that has radiated from the Sun and is available in space at the Earth's distance from the Sun, before it gets into the Earth's atmosphere. That amount is 1,353 Watts/sq. meter or 429.7 Btu/sq. ft./hour, which is called the Solar Constant. That value has some slight variations: (1) the actual output of the Sun has very slight variations which seem to be related to the number of sunspots which exist at the time (about 2%); (2) the distance of the Earth from the Sun varies during the year, being closest on January 3 (about 3.3%); and (3) there are some slight periodic variations in the intensity of the short wavelength parts of the solar spectrum, possibly also caused by sunspot variations on the Sun's surface (around 2%).

Once the solar energy encounters the Earth's atmosphere, a lot of additional effects occur. Whenever light (electromagnetic radiation) encounters any material, there are three things that can happen, the light can be reflected, absorbed, or transmitted. In nearly all actual materials, all three occur at the same time, but usually at different rates. We will consider the major effects here, and also the cumulative effects of everything.

The first major effect starts to occur when the sunlight gets to about 100 km (60 miles) above the ground. There is an abundance of ozone (a variation of the normal oxygen molecules that we all need to breathe) which begins at about that level. (Not actually an ABUNDANCE as it is always less than twelve parts per million of the atmosphere there!) Ozone tends to absorb the shorter wavelengths of sunlight, the portion that is called ultraviolet. The rest of the sunlight is nearly unaffected, so the visible light and the infrared are transmitted downward. This has two major effects: (1) by the ozone absorbing the ultraviolet, it gains heat and so that part of the atmosphere gets warmer. This acts to heat a layer of our atmosphere called the Stratosphere from the top. There are probably convective circulation cells in the stratosphere, but little research seems to have yet been done to study it, and it is still unclear if that action has any effect on weather or anything else; and (2) since most of the ultraviolet energy is absorbed by the ozone layer, very little remains that gets transmitted down to the surface where we are. There is still enough to cause us to get a severe sunburn, but we are protected from the probable fatal effects of getting all the ultraviolet radiation that was present in the original solar radiation. This last is why many scientists are extremely concerned that human activity seems to be damaging the ozone layer. Some chemicals such as ones called CFCs (chloro-fluoro-carbons) such as Freon seem to rise up in the stratosphere and react with the ozone to break it down. Such chemicals provide free-radicals of chlorine, which can react in the following way: Cl^- + O₃ = OCl + O₂ and then OCl + O₃ = Cl^- + (2)O₂. A single chlorine free radical can therefore cause two ozone molecules to break down into three normal oxygen molecules and then even wind up ready to do it again.

If human activity should ever completely destroy the ozone layer (which was nearly caused over the South Pole), we would be exposed to as much as four times as much of certain wavelengths of ultraviolet energy as we are now. Rather short exposure to sunlight on your skin could then cause serious damage (even cancer) if the ozone layer was completely gone. Could you spend your life without EVER having any of your face or skin exposed to sunlight for half an hour? Anything more could cause skin cancer, some kinds of which could kill you. After a CFC ban in 1989, it appears that this problem is improving and it is thought that the ozone layer might again be fully recovered by around 2050.

As the sunlight proceeds downward toward the earth, it passes an altitude called the tropopause. Nothing special occurs there but it is the altitude that separates the stratosphere (above it, and heated from above by the ozone heating) and the troposphere (below it, and heated from below by the various effects described in the following text). It is therefore the coldest portion of the Earth's atmosphere (except for a region extremely high, almost where satellites orbit). Around the ozone layer (32 miles or 160,000 feet or 50 km up), the atmosphere is around 20°F or -5°C, fairly warm. At the tropopause (8 miles or 40,000 feet or 13 km up), it is far colder, around -70°F or -55°C. That is roughly the altitude that jet airliners fly at. Below that altitude, the atmosphere becomes much warmer, getting up to an average of around 59°F or 15°C at sea level.

Once the sunlight has passed the tropopause, it gets into the troposphere, the layer of the atmosphere that we live in and which all weather occurs in. Most specifically, there is carbon dioxide and water vapor in the troposphere, both of which absorb a lot of the infrared part of the sunlight. This absorbed energy heats up the air and causes convection (circulation) to occur in the atmosphere, which causes all the Fronts and other air circulations you see in the daily weather forecasts. It is a primary energy source for most weather phenomena.

When scientists suggest that more severe weather might occur (such as stronger hurricanes and tornadoes and thunderstorms) it is because of this. If more carbon dioxide is present in the atmosphere (and it definitely is), then more solar heat is absorbed into the atmosphere by that carbon dioxide, and there is therefore more energy present to drive convections and the other motions of the atmosphere. Much of the detail of such things is still unknown, but the basics are definitely known, and greater carbon dioxide concentration seems certain to enable stronger storms. That added energy to the atmosphere has to somehow get "used up", and two common ways that happens is getting converted to kinetic energy (air motion) by convection and getting converted to electrical (lightning) energy as related to cloud formation.

The water vapor in the atmosphere starts out low in the atmosphere where it is warm, which is why it evaporated from liquid surface water in the first place. If it rises in the atmosphere (due to convective circulation as mentioned above), it gets to cooler levels. If the tiniest specks of dust are present, the water vapor can condense out onto those dust specks to form very tiny droplets of water. The droplets are so tiny that they do not fall, because the convective upflow of the air easily supports them. This is how a cloud forms. It is no longer water vapor but actual water droplets, just really small ones! Clouds are important in our discussion here because they are very reflective of visible and infrared sunlight. This reflected light therefore never gets down to us on the surface, and it also does not heat the clouds or air, but simply bounces back out toward outer space.

The amount of carbon dioxide in the atmosphere, the amount of water vapor and the quantity of clouds are each quite variable, and so these various effects of absorption and reflection can have minimal effect (for example, on a cloudless summer day in a desert) up to an extreme effect (for example, an extremely overcast day with thick clouds). These effects are the primary ones that drive the Earth's weather, and since they are each so variable, it makes weather forecasting the difficult job that it is. Even the best weather forecaster can be wrong when unexpected changes occur locally in any of the above, or in any of their consequences (specifically, the convection cells and the winds).

Summary so far: If we consider there to be 100% of incoming solar energy in space approaching Earth, about 19% of that energy gets absorbed by all the components of the atmosphere. This results in a maximum of about 81% of the solar constant ever being able to reach the Earth's surface, around 340 Btu/sq. ft./hour or 1,070 Watts/sq. meter. On the clearest possible day, this is about the best solar energy input that is possible. However, on the average, clouds in the Earth's atmosphere reflect another 25% of the incoming sunlight back off to outer space. Since cloud creation tends to occur in mid-latitudes (where most of us choose to live), cloudiness is even greater in such areas, and so the local reflection of solar energy back to space is even greater. Even though the average for the Earth is 25% reflection off the clouds, it is commonly about double that (on an average) for cities like Chicago, where average sky clearness is only described as around 35%. Therefore, for practical application, it makes sense to think of (100% incoming solar minus 19% that gets absorbed by the atmosphere minus 50% (locally) that is (average) reflected by cloud cover, leaving only around 30% of the solar energy to actually be potentially usable, on the scale of 130 Btu/sq. ft./hour or 400 Watts/sq. meter.

Regarding solar heating equipment, this is when the many heat losses of the equipment itself would be considered. The (glass) cover plate(s) each reflect a few percent of incoming energy and also absorb a small amount, insulation around the (hot) collector loses captured heat, piping or ducts have heat losses, any method of heat storage also loses heat through insulation, and every stage of heat transfer must be "driven" by temperature differentials to get the heat where it is desired. These various issues are why effective solar energy applications require extensive Engineering design. Almost any "solar product" seems to work great on a hot sunny day around noon! But for any application to provide reliable performance, all the different aspects of a system must be maximized. Unfortunately, very few building contractors seem to yet fully understand all the necessary subject areas, and so effective solar heating and other quality solar products are still sadly rare.

We accounted for 19% of the sunlight energy being absorbed in the atmosphere, and another 25% (Earth average) being reflected by clouds. This therefore left around 56% which is able to get to the Earth's surface. Around 9% reflects off various Earth surfaces (such as the ocean surface and light colored deserts), so there is around 47% of the incoming solar energy that actually gets absorbed by the Earth. (There are other sources that have slightly different numbers, where the total solar energy reflected to space is 30% rather than the 34% (25%+9%) indicated here, and that there is therefore 51% of the actual solar energy that gets absorbed by the Earth rather than the 47% number given here. The Handbook of Chemistry and Physics gives a number of 0.367 for the Albedo of the Earth. This is that total reflectivity, in other words, 36.7% (again, instead of the 34% total that we are using here). The reasoning is the same whichever set of numbers are used.)

If we briefly consider a bigger picture, the Earth cannot actually absorb extra energy on an average, because then it would get hotter and hotter and hotter! Therefore, at the end of the day, or year, all the energy absorbed by the Earth (47%) and the atmosphere (19%), a total of 66% must be eventually re-radiated back out to outer space, joining the 25% that was initially reflected by clouds and the 9% that was reflected by the Earth (or 34% total initial reflection). The 66% re-radiation and 34% reflection therefore accounts for all the solar energy getting to the Earth. That means that the Earth as a whole does not heat up or cool off, as an average, because no net energy gets kept as absorbed and all is either re-radiated or reflected out to outer space.

This is true as an average, but it is NOT true for any short time period or for any specific location. Variations are constantly occurring. Specifically, if a thorough "energy balance" is calculated for a location around the Equator, the more direct incoming solar radiation is mathematically easily shown to be too great (by about 15%) when compared to the outgoing radiation FROM the Earth due to its surface temperature. This suggests that the surface temperature of Equatorial regions should be higher than it actually is. Similarly, a careful analysis of the energy balance for the Polar regions shows that more than three times as much outgoing radiation occurs (due to the surface temperature of the Earth there) than the amount of solar energy arriving there, so the surface temperature in polar regions should rightfully be even colder than it is. These two conditions are related. The Earth's atmosphere (actually, the troposphere) gets heated up in Equatorial areas (as described above) and it moves, as winds, in giant circulations called Hadley cells, to carry a surprising amount of that heat energy toward the polar regions. Some estimates are that 250 million tons of air move in these patterns every second, all carrying heat from Equatorial regions to Polar regions, which accounts for the regional differences in the energy balances.

By the way, there is some evidence that suggests that 60 million years ago, the Earth may have had an average temperature of around 22°C or 72°F, and that the average Earth temperature probably fell to around 2°C or 36°F during some Ice Ages in the past few million years, before getting back up to the Earth average of 15°C or 59°F that it is currently. It is unknown if these changes occurred due to changes in the Sun's actual output, in changes in the Earth's orbit around the Sun, or in changes in the composition of the Earth's atmosphere. Since even small changes in the amounts of ozone, carbon dioxide, and water vapor, and in cloudiness, can have extreme effects, it is generally thought that the long term changes occurred due to things that happened inside the Earth's atmosphere. When a large volcano blows up, for example, such as Mount Saint Helens, or Mount Pinatubu, or Krakatoa, millions of tons of find dust particles are shot up into the air. Many are so tiny that they remain suspended in the air for years! They can circle the Earth many times during that time. The dust itself can block sunlight from getting to the surface, while also absorbing extra energy in the atmosphere, and the dust can also provide countless particles for water vapor to condense upon to form more clouds. In both cases, severe changes in the Earth's weather patterns can result. The year 1816 is sometimes called the year without a summer, since it never really got warm and snow fell in most of the United States even in July and August, and that was due to a volcanic explosion a few months earlier thousands of miles away. It is thought that a similar volcanic explosion occurred around 600 AD which might have caused several years of unusual cold for Europe, where crops all failed and starvation was a severe problem.

In this general regard, our modern industrialized society is probably doing a similar effect. All homes are heated with fossil fuels (oil or natural gas or by electricity, which is indirectly usually coal) or with wood or propane gas, all of which creates large amounts of carbon dioxide gas as the primary chimney product. All vehicles (cars, boats, aircraft) use gasoline, diesel oil, kerosene, or jet fuel, which similarly produce carbon dioxide gas as the final waste product of burning. Nearly all industrial processes create even more carbon dioxide gas. The amounts are rather amazing, mostly because the carbon dioxide gas is the primary result of all those chemical reactions combining carbon from any of those fuels with oxygen from the atmosphere.

In fact, you can check in any annual Almanac to confirm that we humans are adding over eight billion tons of carbon dioxide to the atmosphere every year now! That is roughly 144,000,000,000,000 cubic feet of carbon dioxide we add to the atmosphere EVERY YEAR! (NOTE, Feb. 2007: Richard Branson and Al Gore announced an Earth Challenge Prize of $25 million to anyone who can figure out how to REMOVE carbon dioxide from the atmosphere! (Branson included some trickery in that offer, because even a small part of that prize would not be paid until after 2011 and then nearly all of that highly publicized Prize would not be given until the process actually proved effectiveness for the next ten consecutive years! This is from the actual Application Form for applying for that Prize, where it also claims absolute and complete ownership of any technology submitted by Branson and his Virgin company. VERY tricky stuff! I am VERY disappointed with Branson for doing such things!) They must not actually realize the scale of the problem! Even to remove the carbon dioxide we add in a single year, that would involve removing nearly a million times as much carbon dioxide gas as has EVER been removed by all machinery in all history! In a Press Conference, Branson enthusiastically mentioned concepts such as extracting the carbon dioxide from the atmosphere and pumping it down into the ground! That concept is now so politically popular that it already has its own name, Sequestering. He must not realize that it would percolate back up through the ground within months and be back in the atmosphere! I would think that SOMEONE would have remembered all the terror caused when they were told that Radon gas was constantly seeping up through the ground. And Branson and others think that carbon dioxide under far higher pressure would NOT? Duh??? The gesture was admirable for its apparent intent, but extremely unrealistic regarding it actually accomplishing the desired task.)

We reliably also know that the TOTAL carbon dioxide in the whole atmosphere is around 2000 billion tons. (Anyone can simply calculate the total mass of air in the atmosphere by multiplying the 14.7 pounds per square inch atmospheric pressure (which is actually simply the total weight of all the air directly above that square inch) by the total surface area of the Earth, to get 5.136 * 10¹⁸ kg or 1.133 * 10¹⁹ pounds or 5.67 * 10¹⁵ tons. We know that the carbon dioxide component of that is roughly 390 parts per million (by volume). A simple density adjustment gives a total of around 1.98 * 10¹² tons total, the number given above.)

So every five years now we are adding about two per cent more carbon dioxide to the atmosphere! Since it is invisible, we are not very aware of it, but an average car causes tons of carbon dioxide gas to go up into the atmosphere every year! (It is very easy to calculate) If there were only a few cars, there would be no serious problem, but since there are hundreds of millions of cars in use, the total amount of carbon dioxide gas being added into the atmosphere is astounding!

Explaining the Greenhouse Effect

The atmosphere can therefore become far warmer, just because of a "blanket effect" of a surprisingly small quantity of Carbon Dioxide in the atmosphere. We are about to show that we NEED a certain amount of carbon dioxide in the atmosphere!

It is actually easy to calculate the average temperature the Earth's surface SHOULD have, at our distance from the Sun. We know that there must be an average balance between the energy coming in from the Sun (and a far smaller amount that comes up from inside the Earth from radioactive decay going on down there) and the energy being radiated out into space. This is known as Equilibrium. Again, for short times (months or years) and in specific places (equator or poles) there may not be an equilibrium, but that there must be on a longer time scale and for the whole Earth.

We know the amount of solar radiation coming in. Above we gave the value of the Solar Constant. That tells how much energy from the Sun gets to the top of the Earth's atmosphere for each square foot or square meter of area. If we just multiply by the total area of the Earth presents to the Sun (NOT the SURFACE area!), we can know the total amount of energy that is aimed at the Earth. Once we subtract off the amount that gets reflected back out into space, we learned above how much actually gets absorbed into the Earth and its atmosphere. Whatever total amount that is, and we can fairly easily calculate it, it must be the same as the amount of radiation the Earth gives off to space, for that Equilibrium.

There is a well-proven Stefan-Boltzmann law and equation that calculates the amount of outgoing radiation that any body must give off at any specific temperature. We will not go into those details here, but the radiation varies as the FOURTH POWER of the absolute temperature of the surface! Fairly small changes in the average surface temperature of the Earth therefore can really change the amount of radiation we give off to space.

Fact 1

Fact 2

Actually, analysis of air bubbles in ice cores has shown that the carbon dioxide in the atmosphere has fluctuated over time, but apparently within a relatively small range. The Vostok ice-core data (Barnola, Raynaud, Lorius; 2003) gives values for the past 419,000 years which are never above 300 ppm and never below 188 ppm. For the 800 years between 1000 AD and 1800 AD, it stayed very close to 280 ppm, never being more than around 5 ppm away from that.

In 1958, our government started precisely measuring the concentration of many gases, including carbon dioxide, at Mauna Loa mountain in Hawaii, monthly. The annual average for 1959 was 315.83 ppm. By 1989, just forty years later, it was already 352.75 ppm.

Fact 3

In just the past 100 years or so, we have increased that proportion of carbon dioxide in the atmosphere from that fairly constant 280 ppm to about 390 ppm. If the relationship is linear, which seems fairly likely, (and many researchers consider to be true) and if carbon dioxide is the principle cause, which also seems very likely, this indicates that the PRESENT stable temperature for the Earth should be (390/280) * 66 or 92°F warmer than the initial -9°F. [if 280 ppm caused the 66 degree increase, then proportionally, 390 ppm would cause a 92 degree increase, to a current 83°F.]

Conclusion 1

Not even counting the additional carbon dioxide we will pump into the atmosphere in coming decades, we have ALREADY caused a twenty-five degree F rise in the atmosphere (which may take many decades to actually appear because of how massive the atmosphere and Earth is). But there can be no doubt from this reasoning that we have ALREADY caused a coming 25°F rise in the average temperature of the Earth's atmosphere and surface. So when alleged "experts" claim that there will only be a two-degree rise over the next hundred years, they clearly have no idea what they are talking about!

We can even use published data to confirm this! Any annual Almanac can confirm that the world now sends around 8 billion tons of new carbon dioxide into the atmosphere each year, nearly all of which comes from vehicle exhausts and electric power plants. We know that there are around 1800 billion metric tons (or 1,980 billion standard tons) of carbon dioxide in the atmosphere already (using the Mauna Loa data figure from 1987). [We know the total mass of the atmosphere and we know the fraction of it that is carbon dioxide.] Since the 1980 billion tons of total carbon dioxide is the 350 ppm, then the 8 billion tons that we add each year must logically be increasing that fraction by about 1.4 ppm every year [simple proportion]. This actually seen in the data. From 1979 (336.68 ppm) to 1989 (352.75 ppm) there was an increase of 16.07 ppm in ten years, or an average of 1.6 ppm each year.

We have shown that 1.4 ppm of that is clearly directly due to the carbon dioxide that humans have added to the atmosphere. The small remainder may be due to the massive removal of rain forests, which have eliminated countless trees from being able to remove carbon dioxide from the atmosphere.

And now that China is going industrial, on an enormous basis, this contribution will get far faster and worse.

We can project this ahead, with reasonable assumptions of China's contributions, where the annual increase such that the annual increase rises to around 2.2 ppm.

Conclusion 2

This is catastrophic beyond imagination! Few trees will be able to survive and actually live and expel oxygen at 35°F hotter than they are used to. They can't go anywhere, so they are nearly all likely to simply die. This would mean that THE major source of oxygen in the atmosphere no longer existed. Food supplies, too, would be essentially gone. As animals and humans lived and breathed and used it up, far less new oxygen would be formed. This might easily represent a death sentence for all animal and human life on Earth, except for very small numbers of individuals who were somehow able to survive on minimal oxygen. We know that there are about 1.2 * 10¹⁸ kg of oxygen in the atmosphere. We know that photosynthesis of the world's plants adds around 2.6 * 10¹⁴ kg of oxygen to the atmosphere every year, and we know that the vegetative decay of dead trees and plants and animal wastes and carcasses and respiration uses up roughly that same total every year.

In the event that all plants and trees died, humans and animals would then only have the existing oxygen in the atmosphere on which to live. While there were still plants to rot and decay, that 2.6 * 10¹⁴ kg/year of oxygen would get used up (and never be replaced), of the existing supply of the 1.2 * 10¹⁸ kg. This implies that there is enough oxygen in the atmosphere for humans and animals to breathe for around 4,600 more years. Actually, more, because once there were no more plants to decay, the consumption of oxygen from the atmosphere would be greatly reduced.

So, the concern about running out of oxygen is not one we truly need to see as urgent, although once the oxygen is gone, that would certainly be it for humans and animals on Earth!

However, of all or most plants died, the ENTIRE source of food for all animals and plants would end. A very small number of humans might be able to survive for a while, by possibly manufacturing food nutrients from fossil fuel, but such a situation, total lack of vegetable and animal food, would be incredibly grim, and THAT would occur within a matter of months of plants all dying.

It turns out that this concept is not even new! (Archer and Barber, 2003, Photosynthesis and Photoconversion, Chap 1, p.4, calculated that several years ago, and expressed the concern that the end of human and animal life may soon happen.) They also noted and calculated that if all plants were gone and people were still breathing oxygen, we would consume all the remaining oxygen in the atmosphere surprisingly quickly! (But we would run out of food far quicker.) They calculated the oxygen consumption to take around 4,600 years. Few food crops will be able to survive that great temperature increase either. That suggests that, very quickly, in months, that the entire food supply for humans and animals might end (ibid).

Confirmation

By the way, the fact that this matches so extremely well seems to imply that the scientists who first calculated the 36°F Equilibrium temperature must clearly have KNOWN all this stuff some years ago! Why didn't they speak up more loudly about the catastrophe that we are headed for?

Much of our possible survival may depend on whether plankton in the oceans can survive such great temperature increases. Plankton is actually the greatest source of oxygen in our atmosphere, with trees and land plants being second. (They are tiny, but there are a LOT of them!) If they can, humanity and animals have a chance. If not, there is no chance at all.

If we really allow the Earth to heat up by 35°F, where nearly all trees and grasses can no longer live, and if plankton also die from that excessive heat (as has been seen in some coral reefs), then there will be two separate new problems. One is that there would no longer be any plant food supply for any animals or humans to eat. That problem would be very urgent, in a matter of months. The other is that there would no longer be any significant way that carbon dioxide could be removed from the atmosphere and oxygen sent into it. Without any source of oxygen, animals and humans could not survive. As noted above, that would likely not be a severe problem for a few thousand years. However, the other half of that, the removal of carbon dioxide from the atmosphere is also a very serious issue.

When occasionally people refer to a "runaway Greenhouse Effect" it is this, where more and more carbon dioxide will accumulate in the atmosphere, without any way for it to be removed (due to the plants being gone), and the global warming would become faster and faster. Currently, plants remove around 300 * 10¹² kg of carbon dioxide from the atmosphere every year. If photosynthesis suddenly stopped, that would end and all that carbon dioxide would remain in the atmosphere. There are currently around 2500 * 10¹² kg of organic carbon in the biosphere, which would all rot and decay over a period of decades, and release about 7000 * 10¹² kg of additional carbon dioxide into the atmosphere. That would essentially quadruple the current amount of carbon dioxide in the atmosphere, which would cause enormous temperature increases due to the effectiveness of that blanketing effect.

It is REALLY important to understand that we have ALREADY fouled things up enough to cause the 25°F rise. It is unavoidable because IT HAS ALREADY HAPPENED. Even if every driver on Earth scrapped all his vehicles today, and all coal-fired electrical generation plants completely shut down today, and we stopped ALL heating of all houses, apartments, stores, factories and schools today, we are STILL going to have that 25°F rise of the average temperature of the entire Earth.

Every additional day of using ANY of those things will just make the situation even more grim. So, when politicians announce that they intend to reduce greenhouse emissions by 20% by the year 2050, it is meaningless. The cows have already run away so there is no reason to talk about some minimal thought of closing the gate 43 years from now.

No politician, and no country, will ever actually DO anything serious about this. As long as they think that "the other guy" won't, they would never agree to absorb the many very grim hardships that are obviously and certainly necessary. Given that there is a valid possibility (mentioned above) that we may have already done enough harm that all sources of oxygen (trees and maybe plankton) will likely die within a hundred years or so, there will simply be denial. We all saw in the movie Titanic that the band kept playing until the very bitter end. We are now all on board, and there seems little doubt that politicians and all other leaders will NOT do anything to adversely affect their countries' businesses' profits or their residents' comfortable lifestyles, until the day when the band can no longer play.

A FEW people probably ARE willing to completely give up driving a car. But not nearly enough to actually make any difference.

We have already "hit the iceberg" but it is an absolute certainty that we will choose to stay in denial, and effectively even be looking for more icebergs to hit! Human nature is something special!

Global Warming Effects of Carbon Dioxide

Once carbon dioxide gas is in the atmosphere, it pretty much stays there, with only one normal method of being used up, by the activity of plants, which take in carbon dioxide gas and give off oxygen as a result of photosynthesis. A few insightful scientists have noted that we STILL have carbon dioxide in the atmosphere from the very first Model T cars of a hundred years ago! The point being, the net amount of this invisible carbon dioxide gas is continually rising in the atmosphere. ^{note 2}

Even that effect that initially seems attractive, of the plants REMOVING carbon dioxide from the atmosphere, is not nearly as wonderful as it first seems. Yes, living plants do that, and remove 300 billion tons of carbon dioxide from the atmosphere each year. But when those plants die, or when the animals that ate them die, everything then decomposes, which has the direct effect of again releasing all that carbon dioxide back into the atmosphere. We might be able to remove a lot of carbon dioxide from the atmosphere for a few months, but when the plants and animals die, it is all back again.

Some evidence of polar ice cap melting is certainly already being seen, but it may be another 20 years before the melting is at a truly rapid rate. At that point, if political leaders finally decide to act to control global warming, there will still already be enormous amounts of additional carbon dioxide gas in the atmosphere for many years, and even decades or centuries, afterward. But no one seems to comprehend the AMOUNT of carbon dioxide involved! We are adding around 144,000,000,000,000 cubic feet of carbon dioxide to the atmosphere every years, just primarily from vehicles and from electric power plants. So even if all sources of carbon dioxide gas were stopped at that time (which no businesspeople would agree to anyway), all the bad effects of global warming would continue for many, many, many years, and those many cities would and WILL certainly be flooded and lost. Most of the very worst effects will likely occur after we are dead, but our children and grandchildren face a future that is dire indeed.

In other words, the damage that we have already done, of causing the equilibrium temperature of the earth to rise from the current 59°F to what should already be 83°F, cannot even be slowed or reversed! Around 140 years from now, it appears that is the unavoidable reality.

Regarding sea levels rising, there is actually also another effect, regarding the density of water at different temperatures. As water warms up, it becomes slightly less dense, meaning it takes up more volume. So even without any ice melting at the North and South Poles, there would be a noticeable (and also easily calculable) sea level rise simply due to that density change of the water. We know that the average depth of the world's oceans is around 12,500 feet. At 58°F (20°C) the specific gravity (essentially density) of water is 0.99823. At 22°C (or 61.6°F), it is 0.99780. (like most other things, it expands when it is heated, so the density drops.) The proportion of these two numbers is 0.99823/0.99780 or 1.00043. So the average depth of the ocean would increase by this proportion JUST BY THE DENSITY DIFFERENCE (not counting any added ice). Therefore, the 12,500 average depth would become 12,505.4 feet, indicating a change in depth of around 5.4 feet, raising the oceans sea level by that amount. If we do this for the 83°F (or 34°C) that we calculated as the present correct Equilibrium temperature for the Earth, this becomes more significant. The specific gravity at that temperature is 0.99440, so we have a multiplier of 1.00385, which gives the average depth of the oceans then to be 12,548 feet. So, even without any ice melting, we have a situation where the sea levels will certainly rise by around 48 feet.

Now, no business and no nation is going to seriously consider cutting back on any activities that now produce all that carbon dioxide gas! "Tell the other guy to cut back, I do not see that I am doing any harm, and I only make a small amount anyway! And it would hurt my business!" If anyone did cut back, by restricting or eliminating home heating, or driving, or almost any industrial process, then it would be seen as a tremendous financial disadvantage for that company or nation, because all their short-term profitability is absolutely dependent on processes that all create carbon dioxide gas in the atmosphere! So, the reality is that NO ONE is going to make the slightest real move toward even limiting the emission of carbon dioxide gas into the atmosphere, until a worldwide crisis is considered absolutely urgent. And, by then, it will be far too late to actually do much. (It is pretty certain that it is ALREADY far too late to save us.) Any actions taken then will really only (potentially) benefit the great-grandchildren of people then living, mostly related to whether they even have any chance of survival. It is hard to imagine the political unrest that will exist in most of the world when hundreds of millions of people lose everything they have, homes, jobs, cars, food, lives. So no one thinks about it today! As long as companies keep making larger and larger (short-term) profits, and keep hiring enough employees, nothing will change. It is a truly sad consequence of modern technology and modern attitudes.

Interestingly, the few leaders who even see a problem all seem to assume that modern technology is so advanced as to be able to easily solve even this problem. However, there really is no "high-tech" solution available, except possibly to make trees and other plants even better at what they do naturally, the process of photosynthesis. But even that only represents a short-term effect, because of there then being even more organic material that has to die and decompose! Someone will probably eventually come up with the idea of covering all the oceans with some sort of fast-growing oxygen producing algae or some other similar plant. And the problem will then be likely to be so desperate that it will be instituted, without ever considering any long-term consequences. Even if such a concept worked to straighten out the carbon dioxide gas matter, it figures that more, possibly even worse, consequences might then result! It seems highly likely that such an effort would quickly totally kill all the fishes ane everything else in the oceans, and most competing plants, too, so the oceans would wind up totally dead-zones after such an experiment. Human beings are an interesting lot!

Political leaders go on television to announce that they WANT to get their country to commit to a 20% reduction of CO₂ emissions by the year 2050! They seem to be oblivious to facts! By 2050, there will be NO petroleum left in the ground, anywhere on Earth. There will be NO natural gas left. There will be NO Uranium that could be mined anywhere. (there WILL still be coal!) So such a statement might seem to be implying that he is caring, and that might be true, but it is the emptiest of all possible statements, because of the facts. The reality will certainly be that, by lack of any fuels, the emission into the atmosphere of carbon dioxide will be nearly completely ended! NOT by any political or business decisions, but by total lack of being able to proceed with the status quo!

Given the rate that China and India are using up those fuel resources (new electric power plants are completed EVERY WEEK!), the projections regarding supplies of fuels lasting (see the Current Energy Resources link below for official government and industry figures) will certainly be far shorter. Nearly complete consumption of all the world's petroleum, natural gas and nuclear seem likely by around 2020, less than 15 years from now! Almost certainly by 2030. AFTER that point, we really will no longer even have the CAPABILITY to send much carbon dioxide into the atmosphere, so THIS problem will disappear because a natural situation, total lack of fuel!

This figures to be especially interesting to watch, as Washington, D.C. is at 25 feet altitude right now! Certainly, within 30 to 50 years, that entire city will be gone and part of the Atlantic Ocean! I bet that the Senators and Congressmen will start really enacting effective laws when there is a foot of water in their offices, within just a few decades!

The recent concern regarding trying to save New Orleans will be entirely forgotten, as New York City (55 feet), Baltimore (100 feet), Boston (20 feet), Philadelphia (40 feet) and most of the State of Florida, all figure to be underwater within just a few decades. There are liable to only be around 30 United States which may still actually exist 140 years from now! (But some will still be islands, where mountains now stand. (Only 15 States seem unlikely to lose significant area in this process.)

This discussion did not include the effect of the change of seasons. In winter (in the Northern hemisphere), the sunlight comes from a lower angle in the sky, so it has to pass through a longer path through the atmosphere, so all those loss effects described above are greater. Also, with the sunlight hitting the Earth at an angle, the light is spread out over a larger area, so any specific (horizontal) area gets less incoming heat. So, even though the Earth is closest to the Sun on January 3 each year, that lower incoming angle (due to the tilt of the Earth's rotation axis) causes less incoming heat during winter and so cooler weather.

All these matters are very complex, and each is the subject of many textbooks! The fact that these are so complex a set of subjects is the normal excuse that businesses and politicians use to still try to deny the very existence of global warming! If and when they ever have to face the reality of the effects they are causing (in their pursuit of short-term profits), they would be forced to also confront the long-term catastrophic consequences of their activities. Interesting, it seems almost certain that the long term financial costs (having to completely replace all the major cities of the world, etc) will be far greater than the total of their short-term profits now! But since those consequences will be faced by businessmen and politicians of 50 and more years from now (AND NOT THEM!), they do not see any real reason to care! I am an advocate of technology, but to see technology used and abused in such terrible ways is really disgusting (personal opinion!)

But this was the first time that any large group like that has admitted that the effects of greenhouse gases (which they say are definitely the cause of the global warming, and that WE directly have done it), will continue for HUNDREDS OF YEARS and possibly THOUSANDS OF YEARS. No one yet seems to realize the importance of that statement. IF we cause the average Earth's temperature to rise by the (VERY conservative, and they admitted that) 4°C (which is about 9°F) by the end of this century, and if we KNOW that the temperatures will continue to rise for hundreds or thousands of years after that, some day, someone will realize what that means! We will have exterminated countless species of animals, maybe even ourselves, because they can't deal with those very high temperatures, and if we cause places like here in Chicago to be 100°F in winter and 180°F in summer (speculating, for maybe 500 or 1000 years from now), even humans may have trouble surviving!

They mentioned another comment that closely matches what I said in this web-page several years ago. They were ONLY talking about the ice sheet in Greenland, which is melting at the amazing rates described above, where about 150 feet wide sections of the edges of the Greenland ice are falling off every single day. They noted in their report that if all of the Greenland ice sheet should melt, that will raise the world's sea level by about TWENTY-THREE FEET!

In a somewhat strange loss of logic, their report seems to indicate that nearly all of Greenland's ice will be gone by 2100, but they then indicate that the oceans are likely to rise by just few feet! Didn't they even read their own report where they clearly state that the direct effect of just Greenland's ice melting will result in a 23-foot rise in all the oceans? I must be missing something here!

Look on a globe at how small Greenland is, especially as compared the HUGE Antarctic ice sheet (about nine times the area). If they are discussing the world's oceans rising 23 feet just from Greenland, can you see that the above (simple) calculations are certainly true, that Antarctica melting will cause that 300 foot rise? And there are many other glaciers and ice sheets, like on most of northern Siberia, Alaska, Norway, Sweden and Canada.

Their report announced that sea levels will rise by at least four feet by the end of this century. But they also admit that is the most conservative of the conservative possibilities.

My personal guesstimate is that sea levels will already be four feet higher than today by 2025, less than 20 years from now! And that by 2050, at least 15 feet and probably more than 20 feet higher than today. And by the end of this century, at least 60 feet and possibly 150 feet higher than today. Nearly EVERY major world city is lower than that! It is good that people are finally at least starting to realize what we humans have done.

I realize that there are readers who will completely disbelieve such comments, and attribute them to some "lunatic tree hugger" However, I am not that. I am a Physicist, who does not really care about political and social consequences of research I do, but instead simply insist that it be as accurate and complete and correct as it can possibly be. My intent here is NOT to be "alarmist" or a "the sky is falling catastrophist". It seems that is the case, but these statements here are all scientifically based and likely to be reliably true.

It is appropriate to note something else here. Petroleum was only discovered around 1870, and only rather small amounts of it were pumped up and refined before around 1950. So we have really done all of this SINCE 1950! And, today, we (the whole world) are wildly burning everything and anything we can find as fast as we can burn it! I mention that here because that report noted that the EFFECTS we are seeing today are actually due to greenhouse gases put into the atmosphere before around 1970. They were rather quiet in their reference that things will certainly get much worse. In other words, their very grim report of today is certain to be spectacularly outdone by climate changes in twenty or thirty years, which no one can even estimate yet. In other words, they were essentially saying that "we are TELLING you that sea levels will rise by four feet, but that we actually know that things will actually become far worse."

Their report also made clear that nothing can now stop this happening, that the best we can hope for is to get the effects to slow down after 2050 IF we greatly stop today. Well, they have to know that we are NEVER going to STOP today! Or ever, until it all runs out!

THIS is one subject that I REALLY would have preferred that my calculations from the 1970s and my comments then (which were all absolutely ignored!) and even this web-page of 2004, might have all been wrong. But since human societies are NOT going to show restraint regarding burning fossil fuels, the locomotive is going to go off the cliff at quite high speed. And there are so many bad consequences that it is terrifying.

Yes, there are some caring individuals who will turn out light bulbs or such things. But at the same time, there are over a billion Chinese who are just now learning to get spoiled like us, AND they suddenly have loads of money to spend. So for each person here who turns off that light bulb, there will be ten in China buying the biggest and the most expensive cars, appliances and everything else. China doesn't know it yet, but they are likely to only have a total of ten or fifteen years max of prosperity before all the major energy sources are gone (petroleum, natural gas, Uranium/nuclear) and they will have serious crises of their own then. It does NOT figure to be any 'fun time' anywhere in the world even twenty years from now. WE did that! We can't blame it on dogs or cows or trees!

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Graph of Carbon Dioxide Concentration 1000ad - present

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