03/18/2010 05:12 am ET Updated May 25, 2011

The Texas Drought, The Florida Chill -- Climate Change?

MIAMI-- The drought that just ended in Texas was not an example or a reflection of climate change. Neither were the unusual, near-freezing temperatures in South Florida.

How confusing. You hear so much about climate change. Then you see what looks like evidence of the phenomenon. And it turns out not to be evidence at all.

"Climate change is slower than that," said Dr. John Nielsen-Gammon, a professor at Texas A&M University and the state climatologist in Texas.

Much slower. Climate change is a decades-long process - a long, slow march that is hard for many people to grasp. Widespread confusion over short-term fluctuations in temperature and long-term trends worry the majority of scientists who are convinced that climate change is happening. They say it leads to apathy, inaction, a do-nothing approach, that could prove to be very harmful.

"People say, obviously, we don't really understand this, so we need to wait until the uncertainty is gone," said Don A. Wilhite, the director of the School of Natural Resources at the University of Nebraska-Lincoln, in an interview. "But the uncertainty will never be gone. If you wait 25 or 30 years to do something, then it's basically too late. If everything we are learning is correct, we need to be doing something now."

Short-term fluctuations in weather - like the drought in Texas and the cold spell in Florida - are caused by historic cycles and so-far inexplicable random episodes, scientists say. They may contribute to long-term averages. But the fluctuations often contradict the big picture. The confusion is aggravated when you hear from the handful of scientists who earnestly believe there is no such thing as global warming and climate change.

Recent polls justify this concern. A year ago, 80 percent of those surveyed by the Washington Post and ABC television said they thought climate change was happening. But as 2009 ended, the percentage had shrunk to 72. The Pew Research Center for the People & the Press in Washington found even less public confidence. It recently got a positive response on climate change of 57 percent, down from 71 percent a year earlier.

Some scientists despair at ever getting people to understand climate change. But Michael J. Hayes, the director of the National Drought Mitigation Center, another unit of the University of Nebraska, said, "You can't just say, 'Let's forget about it.'"

Dr. Hayes and scientists who recently assembled at the University of Miami's Rosenstiel School of Marine and Atmospheric Science, advocate putting more effort into finding clear and simple ways to demonstrate that short term changes in the weather and long-term climate conditions are two different things. Or as Dr. Hayes' colleague, Dr. Wilhite put it, today's cold snap does not mean that "climate change is a hoax."

At the Rosenstiel conference, Ben Kirtman, a University of Miami professor, suggested that public support might be increased if people did not have to envision dire consequences many decades into the future - in some cases long after their likely death. "We really want to get into the question of what's going to happen in the next 10 or 30 years," Dr. Kirtman told the conference, according to the Miami Herald.

Lisa Goddard, a scientist at the International Research Institute for Climate and Society at Columbia University, who also spoke at the conference, said in an interview that studies that distinguished more clearly between "natural variability" in the short run and "man-made climate change" could not only reduce public confusion but also could be useful tools for government officials, farmers and others.

Texas has been through lots of droughts. The latest one, which began to manifest itself in early 2008, was the worst since the 1950s. But five droughts hit the state between 1996 and 2006 alone. The latest one cost farmers and ranchers more than $4 billion, according to state officials.

One of the driving forces in the Texas drought was the way things developed in the Pacific Ocean. Water temperatures in the Pacific were cooler than usual in late 2007 and through late 2008 in what is known as the La Niña effect. La Niña reduces rainfall over Texas. Last fall, the cycle shifted to El Niño. That brought rain to Texas and the drought was broken.

During the Texas drought, temperatures rose into the high 80s Fahrenheit or four to six degrees above average. "That made the climate projections" for the future "more real," Dr. Nielsen-Gammon said. "People were able to feel what a hot summer would be like."

That is one benefit of a shock like the Texas drought. Even though it is not evidence of climate change it gets people thinking about what lies ahead.

The New York Times captured the Texas drought and its dénouement in two photographs. One showed a sweep of dry, cracked Texas ranch land. The other focused on the same terrain. But now there was bright green grass in the foreground, a good-size lake in the middle and more greenery beyond the lake. A family of cowboys and ranch women and young ones was lined up on the grass with their horses. The second picture so captured the sense of renewal and joy that, according to The Times, the family sent it out as their Christmas card.