Barry Smitherman, a candidate for Texas attorney general, responded to Republican activist Donna Garner in a Nov. 17, 2013, email: "Donna, I have been battling this global warming hoax for 6 years now. The earth is not warming ."

Politifact was curious how Smitherman reached his conclusion. He emailed us links to about a dozen articles essentially saying that the planet has not been warming as fast as predicted of late or is, in fact, cooling.

Katharine Hayhoe, co-director of the Climate Science Center at Texas Tech University, called Smitherman's claim incorrect, saying, "Climate is defined as the average over 20 to 30 years or more precisely because atmospheric scientists know that short-term natural cycles in the rates at which heat is exchanged between the ocean and atmosphere can lead to variations in global air temperature over shorter time scales."

Hayhoe cautioned that cherry-picking start and stop years can lead to factually skewed conclusions about temperature trends.

"If you cherry-pick short periods of time, you can end up with nearly any result you want," Hayhoe said. "Only by looking at the entire dataset can you see what the truth is."

From the U.N. International Panel on Climate Change, Fifth Assessment Report, Executive Summary Working Group 1: "Warming of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia. The atmosphere and ocean have warmed, the amounts of snow and ice have diminished, sea level has risen, and the concentrations of greenhouse gases have increased. Each of the last three decades has been successively warmer at the Earth's surface than any preceding decade since 1850.

In the Northern Hemisphere, 1983-2012 was likely the warmest 30-year period of the last 1,400 years (medium confidence).

Ocean warming dominates the increase in energy stored in the climate system, accounting for more than 90% of the energy accumulated between 1971 and 2010 (high confidence). It is virtually certain that the upper ocean (0?700 meters) warmed from 1971 to 2010."

Weapons in school

A few weeks after the Newtown, Conn., shootings, Rep. Stockman, R-Texas, introduced the Safe Schools Act of 2013.

The bill would repeal a federal law that bans everyone except law-enforcement officials from bringing a weapon inside a school. The bill's stated purpose was "to restore safety to America's schools by allowing staff, teachers, and administrators to defend the children and themselves."

The gun debate is fueled by conflicting values and studies. David Hemenway, professor of health policy at Harvard School of Public Health, said he knows of no report that shows that armed civilians provide a protective factor.

In his view, the evidence speaks to quite the opposite conclusion. Our experts could not point to research on whether armed school personnel would afford the students greater safety.

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