Thursday, January 20, 2011

Rich Winsor: Global Warming and Engineering Solutions

Global Warming & Engineering Solutions

January 18, 2011

Climate change is becoming too apparent to ignore; what realistically can be done about it?

What is global warming?

Global warming is also called the “greenhouse effect” whereby sunlight warms the earth and some of the thermal radiation that would normally be expected to leave and thereby somewhat cool the earth is trapped or absorbed by the atmosphere. This effect has been present for much of the time that the earth has been a planet.

Why is global warming important?

Without global warming it is estimated that the earth would be 59 F cooler. So global warming is a good thing. Nevertheless, like many good things, too much can be harmful, and there is mounting evidence that global warming is increasing.

What is the evidence for increased global warming?

Various measures of average surface temperature of the Earth have shown rising temperatures, but this has been only 0.74 deg in the last hundred years, so that is not convincing to some people. This small change has a bigger effect than you might think as shown by the melting polar ice caps, which give more dramatic evidence of global warming.

There are many statistics showing increased CO2 concentration in the atmosphere. One of the most convincing is measurements made at Mauna Loa, Hawaii where CO2 has increased from 315 to 385 ppm in 50 years. There are no signs that CO2 will decrease significantly, especially with the substantial economic growth in India and China.

Munich Re is an insurance company that estimates risk and looks forward rather than backward for potential risks. To quote Bloomberg Businessweek “One of the new risks Munich Re is tracking is climate change. The company has the world’s most comprehensive database on natural disasters, with information going back centuries. It shows that the frequency of serious floods worldwide has more than tripled since 1980, while hurricanes and other severe windstorms have doubled. (This is because warmer sea and air masses lead to greater winds.) ‘Global warming is real’ says Peter Hoppe, who leads the company’s climate-change research.”

By the way, they predict 97% probability of a major earthquake in Los Angeles by 2040.

What problems may be caused by climate changes?

There are many potential changes caused by global warming and the associated shift in the earth’s climate. Of course, climate is a complex system so it is difficult to determine which changes will actually happen and if any given change is due to global warming or just a random variation in the weather. Some predicted changes:

  1. Sea level rise and more and larger storms.
  2. Melting polar ice and retreat of glaciers.
  3. Alterations in habitats and dominance of plants, animals, and insects.
  4. Changes in local climates – droughts, flooding, colder in some areas and hotter in others

Another concern is that there may be a positive feedback of global warming, i.e. some effects of global warming themselves may contribute directly to further global warming, in a vicious circle. For example, melting ice could lead to increased heat absorption because ice reflects more solar radiation than land or water. Also, warmer temperatures in the oceans can reduce the growth of ocean phytoplankton (algae). This is expected to reduce the amount of carbon dioxide taken up by photosynthesis in the ocean, which would increase the overall amount of CO2 in the atmosphere, and hence increase the greenhouse effect. This is a concern because ocean photosynthesis is as large a part of the planet's overall carbon balance as land photosynthesis.

What are the Causes of Global Warming?

Obviously CO2 emissions come from burning petroleum products like gasoline, diesel fuel, jet fuel, propane, and heavy fuel oil. Burning coal, natural gas, and biological materials also add CO2 to the atmosphere, but there are other sources that are less well known. The American Association for the Advancement of Science (AAAS) has pointed out a "little known" global problem caused by the unintentional burning of coal. The Association estimates that such fires, started mainly by human activity, contribute significantly to carbon dioxide emissions - as much as 3% of total world output deriving from such fires in China alone.

Deforestation adds CO2 from burning and reduces the amount of CO2 that is consumed. Production of fertilizer and cement also add significantly to atmospheric CO2.

Methane is a much more effective greenhouse gas than CO2, and it is produced by landfills, animals, and termites. It is estimated that methane currently contributes 28% of the warming that CO2 contributes.

Why do people deny global warming?

There are many reasons, so I will try to list the three most common ones:

1. Economic – Reducing consumption of relatively inexpensive fossil fuels will cause serious economic changes. Note that out of all the major scientific organizations, only the American Association of Petroleum Geologists has not affirmed the consensus view on global warming (they haven't taken a firm stand).

2. Government Conspiracy Theory - Solving global warming implies government action. Many have a strong political and ideological bent against government regulation. There's a fear that individual freedoms will be infringed upon.

3. Religious and/or Anti-science – Some people think that science causes problems and that we should rely on religion and “common sense” and avoid complex rational thought and scientific theories. Therefore, they believe that we should not try to affect global warming.

How are we going to solve this problem of global warming or climate change?

There are at least four categories of actions that can be taken to mitigate global warming:

1. Reduction of energy use (conservation)

2. Shifting from carbon-based fossil fuels to alternative energy sources

3. Carbon capture and storage (carbon sequestration)

4. Planetary engineering to cool the earth

The first three of these could theoretically be effective, but they have had little impact. Many small efforts can help reduce global warming, but reasonable estimates show that they will not be sufficient. Global warming is like a runaway freight train going downhill and efforts to reduce it have failed and will continue to fail. India and China are industrializing, as is most of the rest of the world, and energy consumption is increasing. Countries and people will not significantly cut back on consuming energy for heating and cooking, transportation, manufacturing, etc. Anyone who suggests that we all get together and solve the global warming problem is simply being unrealistic. None of the efforts of the past have had a significant effect on CO2 production, and the nature of human existence has shown that nothing significant will be done until there is a crisis, and that will be too late.

So I believe that conservation and alternative energy are not going to solve the problem, and carbon sequestration is expensive and will therefore be only a token effort. I believe the solution to global warming must be planetary engineering, so let’s explore this topic.

What are the issues with planetary engineering?

First, let me define engineering. Engineering is the application of scientific and mathematical knowledge to practical ends such as the design, manufacture, and operation of efficient and economical structures, machines, processes, and systems. Of course, engineering, like science, can be used for beneficial or detrimental purposes, but here we want to use engineering principles to address the global warming problem. One of the major considerations in any engineering activity is cost, and here I am using cost in a very general sense. Costs include raw materials, manpower, detrimental effects on other activities, etc. We must be very aware of costs because if we are spending an inordinate amount of resources on planetary engineering, we will be using resources that might better be employed to solve many other problems, such as disease, hunger, and the general standard of living. We must use resources wisely as we conduct planetary engineering.

We have to consider many possible solutions to global warming, conduct experiments and pilot studies, generate cost estimates, and determine the benefit vs. cost of the alternatives before starting a major program to combat global warming. Of course, this investigation will take time and resources, but starting a major effort without the necessary studies risks wasting much more than would be gained by an early start. For example, T. Boone Pickens started on an ambitious program to generate wind power in Texas. Unfortunately, there was little market for semi-reliable power far from customers and the cost of generating and shipping the power was high, so he is now trying to sell the operation.

Another consideration with planetary engineering is unintended consequences which often arise from major activities. Some of these could be beneficial spin-offs, while others could be quite detrimental to some portion of the ecosystem. However, we must not be paralyzed by the possibility of some unknown problem. We must do our best to choose a wise solution to global warming with the overall objective of improving life on earth.

Proposed Planetary Engineering (Geoengineering) Solutions

The cost per ton of CO2 pollution reduction is $10 to $30, while estimates are that geoengineering can give the same effect for $0.7. Therefore, I think we must invest in serious studies of geoengineering, like we invested in space exploration. I will mention some geoengineering concepts, but it is premature to recommend anything without pilot studies, improved models, and further calculations by multiple investigators.

  1. “Doping the stratosphere” involves releasing aerosol particles above the clouds to reflect sunlight and thereby cool the earth. Sulfur dioxide is generally suggested as the material to be used to create the reflective aerosol, and it might be provided by burning high-sulfur fuel in high-flying intercontinental jets.
  2. “Cloud brightening” involves releasing fine water droplets to create more reflective clouds and/or more clouds.
  3. Lighter colored rooftops and roads have been suggested to reduce absorption of sunlight.
  4. Ocean nourishment including fertilizing with iron has been proposed to encourage growth of CO2-consuming plankton.
  5. Another concept is “space sunshades” to obstruct solar radiation with space-based mirrors or other structures.
  6. Building thicker sea ice by spraying seawater onto existing ice has been proposed to increase the polar ice caps and reflect more sunlight.
  7. Air capture of carbon dioxide and its sequestration has also been proposed.

As I suggested before, the cost effectiveness, side effects, and risks must be considered before embarking on large-scale geoengineering. Nevertheless, it is time to begin serious studies of planetary engineering alternatives, and there is growing support for this because the cost is much lower than alternatives.

Some Risks of Planetary Engineering

Changing global temperatures without lowering the level of greenhouse gas concentrations is a source of concern. One risk is the possible lessening of rainfall, and the possible weakening of the Indian or African monsoons is a particular worry. In the wake of the Pinatubo eruption, there was some diminution in rainfall, and some model results suggest this might also result from solar radiation management strategies.

Not all planetary engineering technologies are equally at risk on this score. The more localized nature of marine cloud whitening may represent a positive advantage. Because of anxiety over the effect of extra cloud condensation nuclei on rainfall, areas upwind of land with a drought problem could be avoided. In a sense, the more localized nature of marine cloud whitening operations is an offset to the potential disadvantages of the patchy effects of this approach.

Summary

With that I will finish and restate “the much lower cost of a planetary engineering solution to global warming should be seriously considered since conservation, alternative energy, and carbon sequestration will be delayed and avoided because of the societal costs.”

For more information on Climate Engineering, I recommend “An Analysis of Climate Engineering as a Response to Climate Change” by J Eric Bickel and Lee Lane. They conclude “the results of this initial benefit-cost analysis place the burden of proof squarely on the shoulders of those who would prevent such research.”

No comments: