Beck said others argue the record is flawed because of differing equipment, changing technology and varying altitudes.
But he said while it may be true that the record could be improved, the hundreds of thousands of measurements taken all over the world in different ways and over more than 100 years overcome the difficulties.
"It's difficult to establish a confident temperature trend," he said. "But there's no reason to believe that scientists haven't handled that problem."
So goes the theory of global warming: The average surface temperature of Earth is gradually getting warmer partly because of increases in human-caused greenhouse gases in the atmosphere.
But some of the most highly-trained skeptical scientists argue that the climate isn't as sensitive to the key greenhouse gas carbon dioxide as the greater scientific community thinks.
"I believe the fundamental basis, which is that CO2 is a greenhouse gas and we are adding it to the atmosphere," said Roy Spencer, a principal research scientist at the University of Alabama in Huntsville. "Where I depart is on this issue of how sensitive is the climate system to that little bit of warming."
Based on satellite observations of Earth, he said he's found evidence that the climate is very insensitive.
Spencer said it makes a big difference. If the climate system isn't as sensitive to carbon dioxide and the temperature change isn't as significant, he said, "then human caused global warming becomes a false alarm."
But others in the scientific community argue that the climate sensitivity hypotheses don't fully explain global temperature trends.
Jay Gulledge, the senior scientist and director the Science and Impacts Program at the Pew Center on Global Climate Change, said this argument is the most common one maintained by the most skeptical of the qualified scientists. But he emphasized that when examined by peers, it has not gained traction.
"It has failed in their eyes to explain their observations," he said.
The research published by scientists who subscribe to this argument gets published in journals and is legitimate, he said, but the theory can't explain key historical temperature changes.
Another common claim is that solar activity is causing global warming. Skeptics who subscribe to this claim argue that the sun's output is driving the upward global temperature trend.
But Gulledge said that scientists have collected large amounts of data on the sun's activity. Some data goes back 30 years, some goes back as far as 600 years, he said, and none of it supports the theory.
"Every single measurement of what the sun is doing shows that the sun is changing in the opposite direction of what would be required to produce a warming of the earth," he said.
As the so-called "climategate" scandal unraveled over the past few months, some skeptics went from challenging the science to challenging the messengers.
In November, thousands of hacked e-mails from a leading climate research center in the U.K. fueled debate.
Some skeptics saw them as evidence that researchers were exaggerating their claims and burying opposing evidence.
At the time, conservative blogger Michelle Malkin said it promised "to be the global warming scandal of the century."
"Right now, the biggest thing is just the attacks on the climate science community," said Beck.