Earthquakes are rattling the globe this year, but the number of atmospheric catastrophes, like floods, is multiplying faster as the world warms, according to the lead climate researcher at a global insurance corporation.

Haiti, Chile and China suffered jarring quakes in the first half of 2010, resulting in more than 225,000 deaths. Nearly all of those occurred in Haiti during a January shake, marking a global spree of tectonic rumblings that caused $38 billion in total losses, according to catastrophe data collected by insurance giant Munich Re.

But while the number of earthquakes that affect people is rising, it is eclipsed by a faster increase in the frequency of floods, storms and heat waves over the last 30 years, said Peter Höppe, who heads Munich Re's climate research center.

"There is a pronounced larger trend in the weather related events, compared to the geophysical events," he told reporters yesterday in a review of this year's damages.

"As we have these different trends, we have to find the cause for these different trends, and it's quite the probability that global warming has already, and in the future even more, will contribute to the increases in weather-related events."

There have been 440 catastrophic natural events worldwide this year. Only once—in 2007—has that number been exceeded in the first half of any year, Höppe said.

The United States has experienced a "tame" six-month period, having largely avoided damaging tornadoes and thunderstorms, said Carl Hedde, an expert on "risk accumulation" with Munich Reinsurance America.

But that's an odd outcome that likely won't be repeated, or could be erased by this year's hurricane season, which experts believe is twice as likely than normal to whip beaches and flood shorelines.

"In spite of the low total for the first six months of 2010, the trend indicates that thunderstorm losses have quadrupled since 1980," Hedde said.

More catastrophes, or just more people?
There's no dispute that the number of catastrophes is rising. In 1980, for example, the world saw half as many events—less than 200—in the first six months as during the same period this year.

But there's lots of dispute about why it's happening. Is it explained by people suffering more damages as they move toward the water, and to what extent, if any, is climate change riling up the weather?

Just look at Florida. Its population has skyrocketed in recent decades. That ignited a building boom along its shorelines—and a huge jump in damages when a hurricane rambles ashore.

"If Florida had the population it had 40 or 50 years ago, that simply would not be the case," said Bob Hartwig, president of the Insurance Information Institute.

"So yes, there is a very strong socioeconomic component," he added, referring to population movements. "That accounts for the vast majority of both the number and particularly the cost of events. There is a climate component, too, which is more difficult to quantify."

Scientists are not ready to say they can link climate change to a specific event, like Hurricane Katrina. But many point to the growing body of evidence around, especially, increasing downpours and floods as a likely impact of warmer temperatures.

Höppe also highlights the comparison between the much faster rise of storms, floods and weather extremes and the slower increase of earthquakes, which are not affected by climate change.

All of those disasters, including earthquakes, he acknowledges, have become more frequent in part because there are more people on Earth to witness them.

"But as we see a much larger trend in respect to floods, for example—a quadrupling, four times as many events, and this just in a time frame of 30 years—we have to look for other reasons," Höppe said. "And we don't have a different explanation than that global warming is one of the contributors to that."

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC., 202-628-6500