Whence the Wacky Weather?

June 2012 was the warmest month on record in North America. July is on pace to exceed June. Here in the Northeast, we have been spared the searing triple digit heat waves that everyone from Denver to Washington DC has experienced. But we have had wave after wave of intense “precipitation events” like last night’s storm.

Is this wacky weather normal? Or is this caused in part by all the stuff we put in the atmosphere?

Two years ago I wrote a book that summarized what scientists knew then with a high degree of certainty about the growing human impact on climate. The news was grim. Since then, the climate disruption news has only grown worse, as the scientific findings have grown even stronger. 

What did we expect? In 2009, when 167 countries met in Copenhagen, the two nations responsible for 40% of global carbon emissions, the United States and China, committed no one to anything to curb emissions.

As Bill McKibben writes in the current issue of Rolling Stone,

“If the pictures of those towering wildfires in Colorado haven't convinced you, or the size of your AC bill this summer, here are some hard numbers about climate change: June broke or tied 3,215 high-temperature records across the United States.”

For the history of the U.S Drought Monitor, which began in 1999, this summer we have the largest spatial extent of drought on record: almost 64% of the contiguous US experienced drought conditions last week.

The U.S. Department of Agriculture to declared more than 1,000 counties in 26 states natural disaster areas effective July 12, 2012, establishing the largest natural-disaster area in U.S. history.

Earlier this month, the National Climatic Data Center released the 2011 State of the Climate, a peer-reviewed report complied by 378 scientists from 48 countries around the world. This annual summary of global climate events is full of stuff that data hounds like me adore. For example,

“In 2011, oceans were saltier in already drier areas and fresher in already rainy areas, indicating an increase in the global water cycle.” 

In plain English, more water is moving through the atmosphere so dry areas (like the American Southwest) are becoming drier and wet areas (like New England or Florida) are becoming wetter.

The mounting evidence suggests that nothing else explains the disruption of climate patterns except the human activity of burning fossil fuel, paving our world, wiping out forest and jungles, and polluting vast volumes of water.

Not sun spots, not rotational wiggles of the Earth, not El Niño or La Niña–just plain old modern fossil fuel based civilization, as we know it, is the chief culprit.

McKibben goes on to explain that our Earth is one big connected system:

“A third of summer sea ice in the Arctic is gone, the oceans are 30 percent more acidic, and since warm air holds more water vapor than cold, the atmosphere over the oceans is a shocking five percent wetter, loading the dice for devastating floods.” Read more. 

A report published in Science this week shows how the intense summer thunderstorms–like the one we had last night–pump water higher into the upper atmosphere than was known before.

Why does that matter? Put on your sun block! 

Strong thunder storms send moisture so high that this water content is mixing with aerosols we dumped there for decades (such CFCs and refrigerant gases, now banned on the ground, but still lingering above). This moisture arrives in the ozone layer of our atmosphere–normally drier than a desert–where its sets up new chemical reactions, weakening the ozone layer that protects us from ultraviolet light rays.  So now a link appears to be emerging between thunder storms, skin cancer rates and ozone warnings. Who knew?!

Bottom line, I highly recommend McKibben's very readable article!