Extreme floods, prolonged droughts, searing heat waves, massive rainstorms and the like don’t just seem like they’ve become the new normal in the last few years—they have become more common, according to data collected by reinsurance company Munich Re see Part 1 of this series. But has this increase resulted from human-caused climate change or just from natural climatic variations? After all, recorded floods and droughts go back to the earliest days of mankind, before coal, oil and natural gas made the modern industrial world possible.Until recently scientists had only been able to say that more extreme weather is “consistent” with climate change caused by greenhouse gases that humans are emitting into the atmosphere. Now, however, they can begin to say that the odds of having extreme weather have increased because of human-caused atmospheric changes—and that many individual events would not have happened in the same way without global warming. The reason: The signal of climate change is finally emerging from the “noise”—the huge amount of natural variability in weather.Scientists compare the normal variation in weather with rolls of the dice. Adding greenhouse gases to the atmosphere loads the dice, increasing odds of such extreme weather events. It’s not just that the weather dice are altered, however. As Steve Sherwood, co-director of the Climate Change Research Center at the University of New South Wales in Australia, puts it, “it is more like painting an extra spot on each face of one of the dice, so that it goes from 2 to 7 instead of 1 to 6. This increases the odds of rolling 11 or 12, but also makes it possible to roll 13.”Why? Basic physics is at work: The planet has already warmed roughly 1 degree Celsius since preindustrial times, thanks to CO2and other greenhouse gases emitted into the atmosphere. And for every 1-degree C 1.8 degrees Fahrenheit rise in temperature, the amount of moisture that the atmosphere can contain rises by 7 percent, explains Peter Stott, head of climate monitoring and attribution at the U.K. Met Office’s Hadley Center for Climate Change. “That’s quite dramatic,” he says. In some places, the increase has been much larger. Data gathered by Gene Takle, professor of meteorology at Iowa State University in Ames, show a 13 percent rise in summer moisture over the past 50 years in the state capital, Des Moines.

via Global Warming and the Science of Extreme Weather: Scientific American.

In one of most ironic flip-flops in environmental history, the oil and gas industry is beginning to adapt to climate change. And it’s no wonder. The majority of industry’s infrastructure is located in some of the most climate vulnerable regions on the planet. Nearly 75 percent of the Alaskan pipeline, for example, is built over increasingly unstable permafrost, which is now thawing under warmer temperatures. The Mackenzie Valley in Canada alone has recorded over 2,000 sink holes, rock slides, and large depressions from thawing permafrost.

The pipeline’s famous elevated design was the result of a 20 year study (PDF) on the stability of climate and permafrost from 1950 to 1970. Based on the historic record, engineers designed the supports for the pipeline to withstand some fluctuation in permafrost, but not for the extensive melts now predicted. Indeed, that 20 year study was the one of the coldest periods in Alaskan history. Whoops. Now the supports for the Alaskan pipeline have to be upgraded for a changing climate, and, since the physical lines are heavily subsidized by federal and state governments, it is unclear who will pay.

Now the very industry that publicly denies the very reality of climate change, is looking to climate experts for help. They cooperated with consultants who analyzed oil and gas industry’s ability to absorb impacts from a changing climate. The resulting report was a terse assessment showing that the oil and gas industry was far behind the climate action curve.

extract from: They Know But Won’t Admit: How Oil and Gas Companies are Adapting to Climate Change – Environment – GOOD.

Sceptics argue that there have always been droughts and floods, freak weather, heatwaves and temperature extremes, but what concerns most climate scientists and observers is that the extreme weather events are occurring more frequently, their intensity is growing and the trends all suggest long-term change as greenhouse gases steadily build in the atmosphere.

Killer droughts and heatwaves, deeper snowfalls, more widespread floods, heavier rains, and temperature extremes are now the “new normal”, says Nikhil da Victoria Lobo of the giant insurance firm Swiss Re, which last month estimated losses from natural disasters have risen from about $25bn a year in the 1980s to $130bn a year today. “Globally, what we’re seeing is more volatility,” he says.

People in the most affected areas are certainly not waiting for climate scientists to confirm climate change is happening before they adapt. In Nepal, where the rain is heavier than before, flat roofs are giving way to pitched roofs, and villagers in the drought-prone Andes are building reservoirs and changing crops to survive.

New analysis of natural disasters in 140 countries shows that climate is becoming more extreme. Last month, Oxfam reported that while the number of “geo-physical” disasters – such as earthquakes and volcanic eruptions – has remained more or less constant, those caused by flooding and storms have increased from around 133 a year in 1980s to more than 350 a year now.

“It is abundantly clear that weather-related disasters have been increasing in some of the world’s poorest countries and this increase cannot be explained fully by better ways of counting them,” says Steve Jennings, the report’s author. “Whichever way you look at the figures, there is a significant rise in the number of weather-related disasters. They have been increasing and are set to get worse as climate change further intensifies natural hazards.

“I think that global ‘weirding’ is the best way to describe what we’re seeing. We are used to certain conditions and there’s a lot going on these days that is not what we’re used to, that is outside our current frame of reference,” says climate scientist Katharine Hayhoe of Texas Tech University.

from Warning: extreme weather ahead | World news | The Guardian.