The State of Climate Science

Published June 22, 2015

Few issues have raised more controversy than the science used to justify the theory manmade climate change and the policies developed in response.

Three prominent climate scientists—Dr. Willie Soon, of the Harvard-Smithsonian Center for Astrophysics; Dr. David Legates, professor of climatology at the University of Delaware; and Dr. Patrick Michaels, director of the Cato Institute’s Center for the Study of Science—emphasized the highly complex nature of climate trends. 

Sun Drives Climate

Soon opened his remarks by asking a simple question: “How is the Sun related to Earth’s temperatures?”

Soon says the answer is not an easy as some might think because of huge discrepancies in the quality and kind of data available.

“The Northern Hemispheric record has to be corrected for differences between rural and urban station records,” Soon said. “It is also important to appreciate what time of day data are taken.” What is known as the “urban heat island effect” can result in misleadingly high readings, creating what Soon called “non-climate data.”

While United States temperature data is thorough, this is not always the case internationally, Soon says. In recording global and hemispheric trends, “NOAA and NASA have not given us the data we need,” Soon said. “Rural stations in China do not show the high degree of warming China’s urban-based stations do.”

In the Northern Hemisphere, which has both densely populated urban areas and sparsely populated regions, it is essential to have truly comparable data to form an accurate composite of temperature trends, Soon says.

In the Southern Hemisphere, things are even more difficult. Most of the Southern Hemisphere is covered by water, producing less data than collected in the Northern Hemisphere. Soon says this makes the task of separating natural climate forces, such as volcanoes and solar activity from human activities, such as the urban heat island effect, even more challenging.

In both hemispheres, determining the influence of sunspots on temperatures presents another problem.

“There are 60 different categories of sunspots, and they come in different sizes,” Soon said.

Rainfall Not Getting Worse

Legates turned the audience’s attention from the Sun to precipitation.

“Are we seeing more precipitation extremes?” Legates asked.

Legates says the question is hard to answer because of changes in how we measure what is called “point record rainfall.” The traditional “dip stick” way of measuring rainfall was replaced in the mid-1990s by a more sophisticated mechanism by NOAA, Legates says. 

Once the new rain gauges were in place, NOAA’s Climate Extremes Index began to show a steady rise in precipitation in the United States, but Legates says those readings do not correspond with measurements of stream flows. Higher levels of precipitation, whether as rain or snow, should have resulted in greater stream flow. The fact that they didn’t, says Legates, indicates the higher precipitation readings result from NOAA’s modernization program, and not from climate change.

Climate Rules Unjustified
Policies developed by the Environmental Protection Agency (EPA) targeting emissions from coal-fired power plants came under a withering attack from Patrick Michaels of the Cato Institute.

Citing Michigan v. EPA, a case pending before the Supreme Court, Michaels ridiculed the science EPA is using to justify limiting mercury emissions from coal-generated power plants.  Of the 7,500 metric tons of mercury emitted worldwide into the atmosphere every year, Michaels says, no more than 12 tons come from U.S. power plants.

But Michaels says this didn’t stop EPA from creating a “hypothetical woman” who would consume one pound of freshwater fish every day, 365 days a year. The woman’s consumption of fish would affect her offspring, lowering the IQ of  pregnant women’s children. According to Michaels, EPA even determined what the resulting IQ loss from exposure to mercury would be. In the case of a child with an average IQ, 100, the IQ would drop by .00209 to 99.99791. As a result of this loss of IQ, EPA then calculated that average annual income per person would decline by $1,425. This, Michaels explained, is “EPA math.”

In closing, Michaels says data going back to 1994 and recently released by the University of Alabama show “that we are in the 21st year without any significant warming.”

Bonner R. Cohen, Ph.D. ([email protected]) is a senior fellow at the National Center for Public Policy Research.