Why we must learn to see ourselves as others see us-2

(Continued from yesterday.)

Examples of people’s willingness to believe the best about their own tribe and the worst about the tribe opposing them are not hard to find.

For example, I remember when the Iranian airbus civilian plane was shot down by a US navy warship in the Persian Gulf in 1988. Some people in the US went so far as to suggest that this was a diabolical plan by the Iranians, that they actually ordered a plane full of civilians to pretend as if it were a fighter plane dive-bombing a US navy cruiser so that it would be shot down and thus cause the US to look bad. The only reason such a story would be believed (or even proposed) by anyone was if they started out with the view that Iranians were completely evil and diabolical and viewed their own citizens as expendable.
[Read more…]

Why we must learn to see ourselves as others see us-1

(I have been thinking a lot about the violence that is engulfing the Middle East and the horrific loss of life and homes and other property that is taking place. What follows is a long essay that reflects my thoughts and feelings on it. I have serialized it into four parts and will post one part each day for the rest of this week.)

As the ghastly events in the Middle East keep unfolding, it becomes imperative that we need to radically change the way we view ourselves and others if we are to have any hope of saving the world from an endless cycle of death and brutality.

Robert Burns’ poem To a Louse contains a much-quoted passage that is a good starting point for such a transformative approach.

O wad some Pow’r the giftie gie us

To see oursels as others see us

It wad frae monie a blunder free us

An’ foolish notion

(My feeble attempt at a translation into modern English that loses the charm, appeal and rhythm of the Scottish dialect of the original is:

O for a gift that God would give us
To see ourselves as others see us
It would from many a blunder save us
and foolish thoughts)

Truer words were never spoken. The hardest thing for us to do is to put ourselves in another person’s shoes and see how we, and our actions, might look to them. Instead, as has often been pointed out, our tendency is to judge others by their actions and ourselves by our intentions. As a result, the bad actions of others are taken at face value and their protestations of good intentions are often dismissed as excuses and rationalizations, or even bad faith lies. But when others do the same thing to us, we are deeply offended and become aggrieved. Can’t they understand that we meant well? Shouldn’t our intentions count for something? Such unbalanced approaches cannot help but lead to conflict between people.
The tendency to have such a blinkered view becomes worse when the actions of entire groups of people are involved because the tribal instinct also then kicks in and those blinders provide an even narrower perspective. The worst examples occur when groups go to war against each other. When the ‘we,’ ‘us,’ or ‘ourselves’ becomes our clan or tribe (labeled by religion or ethnicity or nationality) and ‘they’ or ‘others’ becomes members of a different tribe with whom we are at war, the blindness to our own tribe’s faults and mistakes, and the harshness of our judgments of the other side’s actions become pronounced to the point of losing touch with reality.

Take as examples the many current conflicts going on in the Middle East region, be it the US forces battling the insurgency in Iraq or the clashes between Israel and Hezbollah in Lebanon or between Israel and Hamas in Gaza.

If you live in the US, there is a dominant storyline that most people, especially elected officials and the media subscribe to for these conflicts. In this narrative, ‘we’ represent either the US or Israel, and ‘they’ are Muslims or Arabs. ‘We’ are intrinsically good people and ‘they’ are not as good as us, and harbor many bad people. ‘

‘We’ use force only when we have no alternative, and when we do so we are very judicious, careful to make sure that only the guilty are targeted. When innocent civilians are hurt or killed by ‘our’ actions, it is purely inadvertent and accidental. We are quick to express regret and expect that ‘they’ will immediately accept those apologies as genuine, because after all, we are good, humane, decent people.

At the very worst, when some massacre or other atrocity of ‘their’ civilians occurs because of some actions by ‘our’ people, and there seems to be no way of explaining it away as an accident, we are quick to say that these were gross aberrations, the work of a ‘few bad apples’ that in no way represent official policy, or our usual behavior. The actions are portrayed as deviations from our normal high ethical and moral standards. We insist that, as a matter of fair play, the accused must be given all the benefits of due process, be viewed as innocent until proven guilty, and strongly urge everyone to withhold judgment until ‘all the fact are in.’ We then hold extended inquiries and trials, find all kinds of mitigating factors for the actions of ‘our’ errant people, and give the culprits relatively minor punishments.

It is easy to find examples of this. The official responses to the My Lai massacres and the Abu Ghraib prison scandal immediately spring to mind.

The Los Angeles Times of August 6, 2006 has an explosive article by reporters Nick Turse and Deborah Nelson, based on recently declassified secret documents, that this kind of condoning of bad behavior by ‘our’ soldiers during the Vietnam war was much more widespread than originally thought. The long article goes into shocking details of the casual brutality perpetrated on the Vietnamese. Here is just a brief excerpt of the article but you have to read the full story with its details to appreciate the immensity of the crimes committed:

The documents detail 320 alleged incidents that were substantiated by Army investigators — not including the most notorious U.S. atrocity, the 1968 My Lai massacre.

Though not a complete accounting of Vietnam war crimes, the archive is the largest such collection to surface to date. About 9,000 pages, it includes investigative files, sworn statements by witnesses and status reports for top military brass.

The records describe recurrent attacks on ordinary Vietnamese — families in their homes, farmers in rice paddies, teenagers out fishing. Hundreds of soldiers, in interviews with investigators and letters to commanders, described a violent minority who murdered, raped and tortured with impunity.

Abuses were not confined to a few rogue units, a Times review of the files found. They were uncovered in every Army division that operated in Vietnam.
. . .
Ultimately, 57 of them were court-martialed and just 23 convicted, the records show.

Fourteen received prison sentences ranging from six months to 20 years, but most won significant reductions on appeal. The stiffest sentence went to a military intelligence interrogator convicted of committing indecent acts on a 13-year-old girl in an interrogation hut in 1967.

He served seven months of a 20-year term, the records show.

Despite the fact that this kind of thing has happened repeatedly in the past and still continues to happen, ‘we’ are still amazed when ‘they’ see our behavior as approving of, if not condoning, the actions of the perpetrators.

But what happens if ‘our’ civilians are killed and hurt by ‘them’? Then our perspective shifts by 180 degrees. The actions by ‘them’, even if by a few individuals, are not treated as aberrations, but instead are taken as official policy by the opposing government or group because, after all, they are not as good as we are, and are thus capable of not only committing the most heinous crimes, but actually desiring to do so. No apologies or expressions of regret are accepted. Judgment is not withheld but the actions are immediately condemned as wrong and the accused are assumed to be guilty. No calls for due process now. Instead, summarily killing the accused is seen as acceptable, if not desirable. Only swift revenge will appease us, either in the form of military action, quick and severe justice for the perpetrators, sanctions against the offending nations, or financial restitution.

Seeing the world and people in such a weirdly dualistic way is only possible if one values one’s tribal allegiance above all other allegiances, and is willing to ignore reality to maintain the belief that ‘we’ must be inherently better then ‘they.’ Many people clearly think like this. So strong are people’s tribal allegiances that they will hold onto the narrative of the essential goodness and purity of their own side, and the essential evil of the other side, even in the face of clear evidence to the contrary. Even the starkest of facts will not shake their faith.

To be continued. . .

Global warming-9: The demise of Easter Island

Easter Island tends to grip the imagination of people. But the things that people remember most about it (even perhaps the only thing) are the giant stone statues of faces that exist on the island.

Jared Diamond tells the sad story of this island as a warning to us all in a chapter of his book Collapse: How societies choose to fail or succeed, but an earlier essay by him can be seen here. Thanks to MachinesLikeUs.com for the link.)
[Read more…]

Global warming-8: The danger of complacency

The documentary An Inconvenient Truth provides a good introduction to the problem of global warming. The film has three interwoven threads: (1) a documentary showing a slide-show talk that former Vice-President Al Gore gives around the world on the facts of global warming, mixed with film footage of the impact of warming on the environment; (2) the story of Gore’s own interest in this topic; and (3) some self-promotion by Gore.

While I could have done without the last and was not particularly interested in the second, the first part was done very well. It captured most of the state of the science accurately and presented it in a visually captivating way. The film is sobering and well worth seeing to get an introduction to the science behind the problem and a sense of the gravity of the situation we are facing.
[Read more…]

Intelligent Design Creationism movement loses support in Kansas

Back in November 2005, a 6-4 majority of Republicans on the Kansas State Board of Education inserted pro-IDC language into the state’s science standards, going so far as to even write a definition of science to include supernatural explanations for phenomena. (For some background, I wrote earlier about this when I was asked to testify at hearings in Kansas in May 2005 that were being boycotted by the scientific community.)

The standards state that high school students must understand major evolutionary concepts. But they also declare that some concepts have been challenged in recent years by fossil evidence and molecular biology.

The challenged concepts cited include the basic Darwinian theory that all life had a common origin and the theory that natural chemical processes created the building blocks of life.

In addition, the board rewrote the definition of science, so that it is no longer limited to the search for natural explanations of phenomena.

But yesterday, that policy received a setback in primary elections when two seats of that six-person majority group went to Republicans who opposed what their party colleagues had done.

Moderate Republicans scored key primary victories in State Board of education races, wrestling control from conservatives in a battle shaped by the debate over the teaching of evolution.

Conservative Republicans began Tuesday with a 6-4 board majority. However, one of their incumbents lost, and a pro-evolution moderate won the GOP nomination for a seat held by a retiring conservative.

The results left only four board members who voted last year to adopt science standards that questioned the validity of evolutionary theory.

In one of the most watched races on the ballot, Sally Cauble, of Liberal, defeated anti-evolution incumbent Connie Morris, of St. Francis. With 99 percent of the precincts reporting early Wednesday, Cauble held a 54 percent to 46 percent lead in the 5th District, which covers 41 western counties.

Morris, a former teacher, has described evolution as “an age-old fairy tale” and “a nice bedtime story” unsupported by science. She also had drawn criticism for her outspokenness on teaching children of immigrants and sex education. [For more on the colorful Morris, see here.]

Pro-evolution candidate Jana Shaver, an Independence Republican, defeated conservative Brad Patzer of Neodesha, who supported the new standards. Patzer is the son-in-law of incumbent Iris Van Meter, of Thayer, who is not seeking re-election. Shaver won 58 percent of the vote, to 42 percent for Patzer.

Two other conservatives fared better, but face challenges in November, where victories by Democrats could leave the conservative bloc with just two members.

This is the latest domino that has fallen since the Dover, PA court decision, driving the IDC forces back even more. I wrote about these Dover dominoes back in May 2006.

I had thought that the Kansas issue would also end up in the courts. But it seems like the voters have decided to pull the plug first. If the new board in November reverses itself and removes the pro-IDC language, then the people of Kansas will have saved themselves a long and probably losing court battle. I am not sure what the IDC forces will do now. One of their chief architects, law Professor Phillip Johnson of Berkeley, in an interview given after the Dover decision, sounded discouraged:

“I think the fat lady has sung for any efforts to change the approach in the public schools. . .the courts are just not going to allow it. They never have. The efforts to change things in the public schools generate more powerful opposition than accomplish anything. . .I don’t think that means the end of the issue at all.” “In some respects,” he later goes on, “I’m almost relieved, and glad. I think the issue is properly settled. It’s clear to me now that the public schools are not going to change their line in my lifetime.”

It is clear that he thinks the battle had a better chance of being won in the court of public opinion, rather than in the courts of law. But the Kansas primary results are an ominous sign that the tide may be turning there too.

POST SCRIPT: The terrorists have won

The congressional cafeterias on Capitol Hill have quietly gone back to calling them “French fries” and “French toast.” Those congressional superpatriots who felt that they had struck a decisive blow against Islamojihadifascistiterrorism by renaming them “Freedom fries” and “freedom toast” were strangely unavailable to comment on why they had made such a major retreat.

Global warming-7: The current status of the scientific consensus

So what is the scientific consensus about the answers to the key questions concerning global warming?

The British magazine New Scientist gives a review of the state of affairs concerning climate change, along with a handy summary sheet of the main points, and the Intergovernmental Panel on Climate Change (IPCC) report (thanks to Brian Gray of the Kelvin Smith Library who runs the blog e3 Information Overload for the link) provides more detailed information. Here are some tentative answers to the five key questions I raised in a previous post.

1. Is warming occurring? In other words, are average temperatures rising with time?

Here we have to distinguish between the more recent period (starting in 1861) when we have direct measurements of temperature and the prior periods, for which we have to infer temperatures using proxy measures such as using tree rings or bubbles trapped in ice cores that date back 750,000 years.

For the recent past, the IPCC report says that “The global average surface temperature has increased by 0.6 ± 0.2°C since the late 19th century”.

For the period prior to that, the report says “It is likely that the rate and duration of the warming of the 20th century is larger than any other time during the last 1,000 years. The 1990s are likely to have been the warmest decade of the millennium in the Northern Hemisphere, and 1998 is likely to have been the warmest year.”

2. If so, is it part of normal cyclical warming/cooling trends that have occurred over geologic time or is the current warming going outside those traditional limits?

Some skeptics have pointed to relative warm periods associated with the 11th to 14th centuries, and relative cool periods associated with the 15th to 19th centuries in the Northern Hemisphere as evidence that the kinds of warm temperatures we have witnessed recently are part of global cyclical patterns. However the IPCC reports says that “evidence does not support these “Medieval Warm Period” and “Little Ice Age” periods, respectively, as being globally synchronous.” In other words, these were likely regional phenomena.

If we go back even further the report says that “It is likely that large rapid decadal temperature changes occurred during the last glacial and its deglaciation (between about 100,000 and 10,000 years ago), particularly in high latitudes of the Northern Hemisphere. In a few places during the deglaciation, local increases in temperature of 5 to 10°C are likely to have occurred over periods as short as a few decades. During the last 10,000 years, there is emerging evidence of significant rapid regional temperature changes, which are part of the natural variability of climate.”

So while rapid localized changes in temperature have occurred, there is little evidence that these were global in scope.

But there are also suggestions that temperature swings in the past may have been greater than originally thought.

3. Are the consequences of global warming such that we can perhaps live with them (slightly milder winters and warmer summers) or are they going to be catastrophic (causing massive flooding of coastal areas due to rising ocean levels, severe droughts, blistering heat waves, total melting of the polar regions, widespread environmental and ecological damage)?

The answer to these important questions, of course, depend on projections for the future which in turn depend on what actions are taken. The IPCC report outlines possible scenarios here. But some things, such as the reductions in the polar ice caps and snow cover generally are already visible.

One of the most dramatic consequences of snow and glacier melting is a rise in sea levels. It is estimated that a 30 cm (one foot) rise in sea levels results in shorelines receding by 30 meters. Some recent studies suggest that the IPCC report estimates of possible rise in sea levels were low, and more recent estimates are that sea levels could rise by six feet, which would result in massive flooding of highly populated areas the world over. Again, there is limited data so these are still rough estimates. But to my mind, the state of the large ice and snow areas (the polar caps, Greenland, glaciers, and mountain tops) are things that we should watch carefully, and the signs there are not good.

4. How reliable are the theories and computer models that are being used study this question?

The IPCC report points out that “The basic understanding of the energy balance of the Earth system means that quite simple models can provide a broad quantitative estimate of some globally averaged variables.” But only numerical models can provide the kinds of detailed quantitative projections into the future that we need in order to make informed decisions. “The complexity of the processes in the climate system prevents the use of extrapolation of past trends or statistical and other purely empirical techniques for projections.” In other words, just having data about the past is insufficient to project to the future. We also need computer models based on the science and mathematics of climate change. “Climate models can be used to simulate the climate responses to different input scenarios of future forcing agents. . .Similarly, projection of the fate of emitted CO2. . .and other greenhouse gases requires an understanding of the biogeochemical processes involved and incorporating these into a numerical carbon cycle model.” (For details on how the computer models used to predict future trends in climate work, see here.)

The IPCC report concludes that “In general, [the computer models] provide credible simulations of climate, at least down to sub-continental scales and over temporal scales from seasonal to decadal. Coupled models, as a class, are considered to be suitable tools to provide useful projections of future climates.”

5. What are the causes of global warming? Is human activity responsible and can the process be reversed?

Several of the greenhouse gases that influence global temperatures, referred to as “climate forcing agents” (carbon dioxide, methane, nitrous oxide) have recently shown dramatic increases in concentrations in the atmosphere. This graph is perhaps the one that alarms me the most.

figts-8.gif

These sharp increases in greenhouse gas concentrations are clearly correlated with rapid increases in the rate of industrialization and energy consumption within the two last centuries. It seems to me that while individual changes in behavior (such as using less stuff and reusing and recycling more) are important, they must be accompanied by concerted international governmental actions to reverse the trends.

We have a precedent for this kind of concerted international action to solve an important environmental problem. Recall the recent time when there was concern that the ozone layer was being damaged by the extensive use of chlorofluorocarbons (CFCs). International action led to the complete ban on its use worldwide. Now there is some good news.

While ozone degradation continues despite global bans on ozone-depleting pollutants imposed more than a decade ago, the rate has slowed markedly enough in one layer of the atmosphere that scientists believe ozone could start to be replenished there within several years.

“There is compelling evidence that we are seeing the very first stages of ozone recovery in the upper atmosphere,” said Michael Newchurch, an atmospheric chemist with the National Space Science and Technology Center at the University of Alabama in Huntsville.

Evidence suggests that international efforts to reduce chlorofluorocarbon (CFC) pollution are working.

Of course, greenhouse gases are produced by a much more extensive and powerful group of industries than those producing ozone depleting ones, and require greater changes in our own lifestyles. So achieving international cooperation on this will not be easy, as the difficulties implementing the Kyoto treaty suggests. That treaty committed industrialized nations to commit to reducing their emissions of greenhouse gases within the next decade to a level of about 5% below their 1990 levels. Although the US produces about 36% of the world’s output of greenhouse gases (the largest single producer), George W. Bush said in 2001 that the US would not sign the treaty.

Next: The danger of complacency

POST SCRIPT: And sure enough, right on cue. . .

Just last week, I said that the lack of public understanding that climate questions such as global warming only deal with averages over long times and large areas inevitably lead to people drawing the wrong conclusions from short term fluctuations.

Sure enough, yesterday’s Plain Dealer has the following letter to the editor:

We constantly are subjected to news about the coming devastating effects of global warming, which includes the recent story on how it is going to dramatically change Lake Erie and its shoreline. So it’s a bit perplexing to me to see in my most recent FirstEnergy electric bill that during my past 30-day billing cycle, the average temperature in Cleveland was 69 degrees, versus 72 degrees last year. Now, if we are to believe the global-warming doomsayers, a three-degree swing in temperature is cataclysmic. So when will The Plain Dealer begin printing articles about how Cleveland is at risk of entering an ice age if we don’t change our behavior?

Why does the Plain Dealer even print such nonsense? Either they know it is flat out wrong, which means they are deliberately propagating erroneous information, or even the editors don’t know the basics about climate. I don’t know which is more disturbing.

Global warming-6: The public and the paradigm

In the previous post, I discussed how after a paradigm is adopted, scientists tend to communicate only with each other. They are now freed from the need to explain and justify the basic premises of the field to a lay public, and no longer have to make a political case to justify what they are doing. This results in them developing a more technical, insider language and jargon that is opaque to nonscientists, and the technical paper addressed to similarly trained scientists and published in specialized journals becomes the chief means of communication.
[Read more…]

Global warming-5: The emergence of a paradigm

The need to take global warming seriously is not slam-dunk obvious to most people. In my own case, over time I have slowly became convinced that there was an emerging consensus among scientists studying the issue that planetary warming was a serious matter. Like most people, I do not have the time or the expertise to have studied the question in detail, but I have enough respect for the scientific process and the way that scientists make collective judgments as a community that when I see a scientific consensus emerging on anything, I tend to take it seriously. In fact the global warming issue is a great example of seeing, before our very eyes, a transition in science from a pre-paradigmatic state to a paradigmatic state.
[Read more…]

Global warming-4: Is there a scientific consensus on global warming?

Is there a scientific consensus on global warming? Naomi Oreskes from the Department of History and Science Studies Program, University of California at San Diego, thinks so. She published a study in the journal Science (December 3, 2004, volume 306, p. 1686) which argued that the scientific community had arrived at a consensus position on “anthropogenic climate change.” i.e. that global warming was occurring, and that “Human activities . . . are modifying the concentration of atmospheric constituents . . . that absorb or scatter radiant energy. . . . [M]ost of the observed warming over the last 50 years is likely to have been due to the increase in greenhouse gas concentrations”.
[Read more…]

Global warming-3: The science behind global warming

To understand the science behind global warming, it may be helpful to look at a simplified version of the science behind it.

Consider two objects, one that is luminous (i.e., an object that we can see without the aid of a light source) and another that is not luminous. Examples of luminous objects are the Sun (which generates energy due to nuclear reactions within it and sends a lot of that energy out as light) or a light bulb (that converts electrical energy into light energy). Examples of non-luminous objects are the Earth or a person in a room. The energy radiated by the luminous source spreads out in all directions and some of it will fall on the non-luminous object.

What is important to understand is that even what looks like a non-luminous object also radiates energy into space. In fact every object radiates energy. So in a sense, every object is ‘luminous’ in the sense that it sends out energy, but we usually reserve that term for objects that emit visible light. Not all radiated energy is visible. A human being radiates energy at a rate of about 500 watts, or the equivalent of five 100 watt bulbs, but the reason we do not “see” the radiation energy emitted by people is due to it being outside the visible range

The rate of energy emission of an object radiates depends to a large extent on its temperature (it actually goes as the fourth power of the temperature) and the nature of its surface (such as color, texture, material). So just as the Sun radiates energy into space, so does the Earth, except that the Sun’s radiation is much greater since it is at a much higher temperature.

The important thing about global warming is understanding what happens when the energy radiated by a luminous source (say the Sun) falls upon a non-luminous object (say the Earth). Part of it is immediately reflected back into space, and does not affect the temperature of the Earth. But the rest is absorbed by the Earth and, in the absence of anything else happening, will tend to cause the Earth’s temperature to rise. The relative amounts of the Sun’s energy that are absorbed and reflected by the Earth depends on the nature of the Earth’s surface. (As an example, a person in a room absorbs energy from the surroundings at a rate of about 400 watts, thus adding a person to a room is the net heat equivalent of turning on a 100 watt bulb.)

But as the temperature of the object rises due to it absorbing energy, the amount it radiates out again also increases, and at some point the object reaches equilibrium, which occurs when the energy absorbed by it from outside equals the energy it radiates away. Once an object reaches this state of thermal equilibrium, its temperature stays steady.

If for some reason we alter the ratio of energy absorbed by the Earth to the energy reflected, then the state of equilibrium is disturbed and the Earth’s temperature will shift to a new equilibrium temperature. If relatively more energy gets absorbed, then the equilibrium temperature will rise until the energy radiated again becomes equal to the energy absorbed. Conversely, if relatively more energy now gets reflected, then the equilibrium temperature will drop, i.e., the Earth will cool. The people warning of global warming argue that human activity is causing the former situation and they say that the reason for this is that we are changing the nature of the Earth’s surface, especially its atmosphere.

To understand what is happening at the Earth’s surface and atmosphere, we need to understand something about the energy radiated by the Sun. This comes largely in the form of “electromagnetic energy.” This is an umbrella term that encompasses X-rays, ultraviolet, light waves, infrared, microwaves, radio waves, etc. All these types of radiation are identical except for one single factor, which is called the wavelength of the radiation. The items in the list differ only in their wavelengths, with X-rays having the smallest wavelength and radio waves having the longest. (Similarly, all colors of visible light are also identical except for the wavelength, which increases as you go from blue to green to yellow to red.)

When this broad range of electromagnetic radiation from the Sun hits the Earth’s atmosphere, almost all of it, except the visible light portion, gets absorbed by the atoms and molecules in the atmosphere and does not reach us on the ground. Of the portion that does reach the ground, some of it gets directly reflected unchanged and escapes back into space. The remainder gets absorbed by the ground. It is the energy that is absorbed by the ground that is the source of concern.

Recall that the Earth, like any object, also radiates energy away. But since the temperature of the Earth is different from the temperature of the Sun, the distribution of the wavelengths in the energy radiated by the Earth is different from the distribution that we receive from the Sun (although the total energy involved is the same in both cases for an object in equilibrium). This affects how much is absorbed by the atmosphere as it passes through it. Some of the Earth’s radiation will get absorbed by the gases in the atmosphere (i.e., is trapped), while the rest passes through and goes off into space.

This is a crucial point. If the gases in the atmosphere change significantly, then you can change the relative amounts of the Earth’s radiated energy that escapes into space and the amount that is trapped by the atmosphere . The so-called ‘greenhouse gases’ (carbon dioxide, water vapor, methane, nitrous oxide, and others) are those that are very good at absorbing the energy at the wavelengths radiated by the Earth, preventing them from escaping into space.

Global warming scientists argue that human activity is increasing the concentration of greenhouse gases (especially carbon dioxide) in the atmosphere. Hence more of the energy radiated by the Earth is being absorbed and less of the energy is escaping into space. Note that the incoming visible light from the Sun is not affected much by the concentrations of greenhouse gases since they are at a different wavelength, and the greenhouse gases do not absorb them as much. As a result of this increase in the absorption levels of the outbound radiation, the equilibrium temperature of the Earth will rise.

At this point, there are various scenarios that can unfold. One is that we arrive at a new and higher but stable equilibrium temperature. If the change in equilibrium temperature is small, the consequences might not be too disastrous, although there will be some adverse effects such as some temperature-sensitive organisms (such as coral reefs) becoming destroyed or some species going extinct if they cannot evolve mechanisms to cope. If the change is large, then there could be massive floods and droughts and other catastrophes.

The worst case scenario is a kind of runaway effect, where a rise in temperature results in effects that cause an even more rapid rise in temperature and so on, in a series of cascading effects.

Some argue that we are already seeing some signs of runaway effects, and point to the melting of the polar ice caps and the general decrease in glaciers and snow coverage worldwide. Snow is white and thus reflects back unchanged into space almost all the sunlight that hits it at the Earth’s surface. When this snow melts and becomes water, not only is the amount of reflected energy decreased but water absorbs light energy. Hence the major loss of snow cover (apart from adverse environmental and ecological consequences) has a major effect on the reflection/absorption balance of the Earth, shifting it towards greater absorption. So more energy is absorbed by the Earth, resulting in even greater warming, resulting in further snow loss, and so on.

Another possible runaway factor is the amount of green cover. On balance, plants, because of photosynthesis, tend on average to be net absorbers of carbon dioxide and emitters of oxygen. Thus they reduce one of the greenhouse gases. If global warming results in less green cover of the Earth (say caused by prolonged droughts), then that would result in more greenhouse gases remaining in the atmosphere and causing yet more warming and more droughts. Human activity such as deforestation can accelerate this process.

Those are the basic elements of the science underlying global warming and the factors that go into building the models that try to predict long term climate change.

Next: The emerging scientific consensus over global warming.

POST SCRIPT: Colbert takes media apart again

As you may recall, the mainstream media did not take kindly to Stephen Colbert’s demolishing them at the White House Correspondents Association Dinner. Now he takes them apart again.