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 # 417  

June 2002

Climate Change and California Assembly Bill 1058: Is it Hype?

by Willie Soon, Ph.D.

The fear of any catastrophic effects of man-made greenhouse gases continues to terrorize Californians. Assembly Bill 1058, authored by Assemblywoman Fran Pavley (D-Woodland Hills), "instructs" the California Air Resources Board to come up with regulations that allow "maximum and cost-effective" cuts in greenhouse gas emissions from new cars and light trucks by the years 2006-2009.

Why the rush to action called for in AB 1058?

According to Assemblywoman Pavley, "Unless we act, California will experience heat waves, droughts, floods and forest fires that could devastate the economy of the state, including agriculture, fishing, timber, real estate, insurance, construction and tourism... Climate change is already beginning to impact California, the world's fifth-largest economy."

It is important to recognize that Assemblywoman Pavley's extreme claims are deeply rooted in the story lines fueled by flawed computer climate models. In fact, just the mere association of everything bad with "carbon dioxide and global warming" should make one suspicious.

As a scientist, I have been searching for evidence of global warming that can be attributed to rising man-made greenhouse gases like carbon dioxide for some ten years now. Thus far, I have found none.

Computer climate models say that the largest greenhouse gas heating is supposed to occur in air layers a few miles above the earth's surface. Intensive monitoring by both satellites and weather balloons over the last 22 years shows no warming in this part of the atmosphere. Thus, using computer models to confirm the impact of man-made greenhouse gases on California is most likely a futile, if not confusing, effort.


First, the earth's climate is ever-changing, in ways as small as individual molecules within clouds to as large as circulation of the atmosphere and oceans over whole hemispheres.

Also, many climatic processes, such as the way sunlight at different colors or wavelengths interacts with clouds, are still mysterious.

Approximately 5 million different parameters have to be followed for a computer mock-up of the climate system to be accurate. All their important interactions and impacts must be known, but they are not.

Furthermore, a full mock-up, covering all the spatial scales and generating a 40-year forecast of climate change, would take more than 10 to the power of 34 years of supercomputing. In other words, an incredibly long wait and a near-impossible computational task.

Yet, the main goal of serious climate research is to find out if any of the observed regional or global warming can be properly attributed to rising greenhouse gases.

Has California been warming at an alarming rate as suggested by the rapid increase of man-made greenhouse gases? I propose a simple test to answer this question.

Let us study the statewide averaged temperature record for California from 1895 to 2001. Temperature is among the most direct climatic variables one would expect to discern effects from added greenhouse gases. We find two important points: First, the year-to-year temperature fluctuations are very large - about two to four degrees Fahrenheit, so claiming a 100-year warming trend in the California record will not be possible unless those larger year-to-year changes are understood. Second, over the full 100-year temperature record, no systematic warming trend is attributable to the increase in atmospheric carbon dioxide. Still, if one considers that 80 percent of the gradually accumulated carbon dioxide of the 20th century in air came only after 1950s, then one should expect a large warming in the post-1950 period. However, nothing unusual can be seen in the record.

Thus, it is clear that one cannot link temperature change in California to the increase emission of greenhouse gases. Reason for concern over disastrous climatic impacts from greenhouse gases cannot be found in the real climate system so far, but only in the computerized world.

Despite these facts, Assemblywoman Pavley continues to mislead California voters by saying that with AB 1058, "we can help avert a devastating worldwide calamity." This promise is simply untrue because no one really knows if reducing or adding carbon dioxide will actually affect the climate. Indeed, carbon dioxide reduction from California will be extremely small on a global scale. This is why Assemblywoman Pavley's half-truths and the flawed premises for the greenhouse gas emission cuts proposed in AB 1058 mislead and potentially harm Californians.

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This article represents the personal opinions of Dr. Soon and not those of any institution with which he is affiliated.


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