Al Gore’s movie, An Inconvenient Truth, employs a variety of techniques to convince the viewer of what Gore apparently believes: that hurricane activity, melting ice sheets, floods, droughts, etc. are all becoming more frequent because of man-made global warming. His campaign to raise public awareness of global warming is reminiscent of Rachel Carson’s 1962 book, Silent Spring, about the negative environmental and human health effects of using the pesticide DDT.
With the production assistance of Laurie David, Gore’s movie is quite convincing if taken at face value. Huge slabs of glacial ice crashing into the ocean, combined with appropriately general claims by Mr. Gore, give the impression that this is something that mankind has caused.
We are treated to video coverage of all manner of dramatic weather-related events, and we subconsciously make the connections. Hurricanes mean global warming. Droughts and floods mean global warming. Melting and calving ice sheets mean global warming.
But everything shown in the movie was, of course, happening even before global warming became popular. While Mr. Gore does not explicitly claim that these events never happened before global warming, the viewer is certainly left with that impression. While some of what Mr. Gore says does reflect the views of many scientists, he conveniently ignores facts that would greatly weaken his case, especially in terms of causation.
Glaciers: Great masses of ice breaking off glaciers and falling into the ocean are certainly dramatic. But in order for a glacier to just maintain a steady state (keep a constant amount of ice), all of the snow that falls on it during the year needs to be balanced by an equal amount of ice either melting or calving (breaking off) into the ocean. If this did not happen, the glacier would continue to grow, year after year.
While it is true that most of the world’s glaciers have retreated in recent decades, many of those are continuing a trend that was evident even in the 1800s. This is possibly related to the ending of the “Little Ice Age” in the early 1900s. One theory of the retreat of the glacier on Mt. Kilimanjaro attributes it to a significant decrease in precipitation that occurred around the same time.
The Greenland ice sheet seems to have undergone a net decrease in ice in recent years, but this could be natural, or short lived, or both. Despite the rather recent shedding of some large icebergs (which would have happened even without global warming), it is still very uncertain whether the Antarctic ice sheet has had a net gain or loss of ice in recent years. Gore’s factoid about the Greenland ice sheet, if completely melted, raising global sea level by 20 feet is little more than fear mongering.
Hurricanes: The recent upswing in hurricane activity has captured the imagination of everyone. Hurricane Katrina is popularly believed to be the result of global warming. Even though Katrina made landfall east of New Orleans as only a strong Category 3 storm, the failure of a levee and resultant flooding of homes (built well below sea level) made the disaster a record-breaker in terms of monetary cost. Had the same storm hit the mid-Texas coast, there would have been little damage to report.
While we have indeed had an unusually large number of named tropical cyclones in the Atlantic basin during 2004 and 2005, an eventual resurgence of activity has been predicted by the National Hurricane Center for many years. Since the 1970s, we have been in a multi-decadal lull in hurricane activity.
The 1930s through the 1950s was the most active hurricane period during the 20th Century. Then, since the 1960s, the migration of people toward the nation’s coasts and the associated building of new businesses and homes has greatly increased human vulnerability to hurricane strikes. It was only a matter of time before a large loss of life and property occurred, with or without global warming. Thus, even without an increase in hurricane activity, hurricane damage could be expected to increase dramatically due to our greater vulnerability. Given the amount of coastal infrastructure, another hurricane catastrophe could easily occur in the next several years.
A couple of peer-reviewed scientific papers have claimed that the apparent increase in hurricane intensity in recent years has been caused by increasing sea surface temperatures (SSTs). If the increasing SSTs have been caused by mankind, then there is the possibility that stronger hurricanes are due to mankind as well. But now, a new research paper by a National Hurricane Center scientist, Chris Landsea, explains that much if not all of the recent increase in observed hurricane intensity is simply due to more modern measurement methods, especially with satellites.
Global Temperatures: In a particularly effective presentation, Mr. Gore shows a huge display board with a graph of thousands of years of relatively minor temperature variations, then a dramatic warming during the last century. In a clever use of a prop, he climbs aboard a man-lift to be raised high enough to reach the temperature curve at the end of the 20th Century.
You might wonder how we know that the temperature of the Earth was so constant over thousands of years. Well, unless you are a paleoclimate researcher whose job depends upon the validity of such indirect estimation techniques, or a member of the climate research community who has a vested interest in such work, you can be excused for being skeptical. Using tree rings from one species of long-lived tree in the Southwestern United States to infer global temperatures has the peculiar advantage of not being disprovable, simply because we have no actual temperature measurements that long ago to disprove the technique with.
The United Nation’s 2001 report on climate change highlighted what was then a new temperature reconstruction for the last 1,000 years that minimized the temperature variations of the “Medieval Warm Period,” and the “Little Ice Age” that followed it. In this infamous “hockey stick” graph, the 20th Century warming dominates the record, as it does in Mr. Gore’s graph, suggesting that current global temperatures are warmer now than any time in the last thousand years.
But recently, as the result of both a National Academies of Science (NAS) review, and an additional, independent analysis of the statistical methods used in the original study, it is obvious that the thousand-year claim was, at best, dubious. The “warmest in 1,000 years” assertion was downgraded by the NAS review “warmest in 400 years,” a change which was essentially ignored by the press. But even being the warmest in the last 400 years is not such a bad thing, since most of those 400 years occurred during the Little Ice Age.
These are just a few examples of the biased scientific explanations found in Mr. Gore’s movie. An Inconvenient Truth is mostly catastrophe theories explained with cherry-picked science, combined with video of natural events, to paint horror scenarios that have little chance of ever materializing.
At the end of Mr. Gore’s movie, he lists some steps we individually can take to greatly reduce global warming: compact fluorescent light bulbs, hybrid cars, conservation. He says we can even stop producing carbon dioxide. These claims are, at best, very misleading.
If it were easy to produce much of the energy that humanity needs without emitting carbon dioxide, or if it were only a little more expensive, then even a 5% chance of catastrophic global warming would argue for that additional investment. After all, buying insurance is prudent when there is a possibility of catastrophic losses.
For instance, the threat of potentially harmful stratospheric ozone depletion led to the adoption of the Montreal Protocol in 1987, which phased out the manufacture of chlorofluorocarbons (CFCs). Fortunately, the additional costs associated with new designs for refrigeration and air conditioning equipment were manageable, at least in the developed world. In other words, the insurance policy was affordable.
But phasing out our emissions of carbon dioxide will be dramatically more difficult than phasing out CFCs, and thus, dramatically more expensive.
Changing all of the light bulbs in the world to compact fluorescents will have no measurable impact on global warming in the next 50 years. Conservation and buying hybrid cars will also have almost no effect. Industry already minimizes energy use in order to reduce costs and increase earnings.
Everyone agrees that the Kyoto Protocol will have no measurable effect because the proposed emissions reductions are far too small. Most “solutions” proposed or adopted today do little more than make us feel good about ourselves — and help some politicians whose constituents like feel-good solutions.
Renewable, non-polluting sources of energy like wind and solar would require large tracts of land since the energy intensity of those sources is fairly low. These sources will help a little, but cannot solve the problem.
The only way out of the global warming problem (if one really exists) is through dramatically new energy technologies. If hydrogen power ever becomes practical and cost effective, then nuclear power could be used to generate the hydrogen necessary for fuel cell vehicles. And hope still remains for nuclear fusion.
Because of the costs involved, it is vitally important that we make the right policy decisions. Unfortunately, policies resulting from environmentalists’ lobbying have sometimes had disastrous results.
The DDT Lesson
The greatest potential danger of any government policy change is in the form of unintended consequences. Let’s return to the case of Rachel Carson, her book Silent Spring and the eventual ban on DDT by many countries.
The United States and much of the rest of the developed world eradicated malaria many years ago with the help of DDT. Its use was particularly widespread during World War II. Then people fell prey to what is now called the “precautionary principle”: If a new technology has potential negative side effects, don’t use it. Carson presented evidence that DDT caused thinning of eggshells in one species of bird. Indeed, the use of DDT on crops at the time was so heavy that it would have been surprising if there were not some negative side effects, either to nature or to humans.
But policy changes cannot be knee-jerk: One must always weigh costs versus benefits. You drive your car betting that the advantages it provides you outweigh the risks of your being killed in a traffic accident. The same decision is made when you walk across the street. You risk choking to death on food, but you continue to eat. Simply put, no one consistently lives their life according to the precautionary principle.
As a result of many countries’ bans on DDT, nearly 1 million people in Africa die each year from malaria, with many millions more permanently disabled. Most of these are children. It is now known that only a small amount of DDT applied to the doorposts of homes, termed residual spraying, greatly reduces the incidence of malaria. After several years of exploding malaria rates resulting from the discontinued use of DDT, South Africa has now reduced malaria dramatically by resuming its use.
And even though malaria has historically thrived in non-tropical countries, environmentalists now want us to believe that global warming will cause malaria to spread in the future, all the while insisting that DDT not be used now. I suspect that few, if any, of these environmentalists live in Africa. The public would certainly not tolerate a widespread outbreak in malaria in the U.S. DDT would be used to combat it.
In our search for global warming solutions, it is important that we not make the same mistakes that were made with DDT. Even if global warming does become serious, it is clear that solutions will be needed that are both effective and that provide many more benefits than harm.
Good intentions are not sufficient and, as history has demonstrated, are potentially dangerous.
Fossil Fuels: Friend or Foe?
The health, longevity, comfort and infrastructure that the developed countries have created over the years required access to abundant sources of inexpensive energy. Yet, 1 to 2 billion humans still do not have electricity. China and India, through a relatively recent embrace of free market concepts, are now entering their own industrial revolutions. They will not forego their opportunity to elevate their lives above a disease-ridden, back-breaking existence so that some people in the developed countries can feel better about themselves.
The combined carbon dioxide emissions of India and China are now equal to the U.S. and growing rapidly. No matter what you believe about future global warming, the United States’ reducing emissions by, say, 30% will have very little impact without reductions in those countries as well. This is why the U.S. Senate voted 95-0 in 1997 to not even consider ratifying the Kyoto Protocol unless those countries agreed to carbon dioxide reductions.
It is ironic that, even as we enjoy the healthy, well-fed, air conditioned and heated comfort of our modern lives, we heap scorn on the fossil fuel industry for “polluting.” For the huge benefits that fossil fuels have brought to our lives, the current anti-“Big Oil” hysteria sounds like adolescent whining.
Unfortunately, An Inconvenient Truth panders to this public sentiment.