Science Behind Sandy
By Robin Grant
Written for a Science Reporting Class, Carleton School of Journalism
When Hurricane Sandy made landfall south of Atlantic City, New Jersey late on October 29th, it had barreled north toward the East Coast from the Caribbean, leaving disaster in its wake.
Around the same time, a cold front moved across the middle of the United States, bringing cold temperatures and snow.
In a rare meteorological phenomenon, the two weather systems collided as the hurricane came ashore at 8 p.m. EST. The National Hurricane Center in the U.S. received reports of hurricane-force winds gusting over Long Island and the New York metropolitan areas.
The hurricane’s massive and unprecedented storm surge – the wall of seawater pushed ashore by the winds and low atmospheric pressure – caused more damage to the East Coast shores than its powerful surface winds, torrential rains and mountain snows.
In one night, the heart of New York City and the surrounding neighborhoods were inundated with rushing seawater flowing in from the Hudson River. Lower Manhattan, parts of Brooklyn, Queens and Staten Island flooded. Many neighborhoods on the New Jersey coastline were destroyed. Flash floods, falling trees, hurricane-force winds and power outages caused billions of dollars in damage, and killed and injured people in the effected areas.
The massive storm dealt a crippling blow to an international economic and industrial hub. It destroyed thousands of homes and left millions of people without electricity or reliable access to food, water and petrol.
Three days later, as the city grappled with the catastrophic damages, New York City Mayor Michael Bloomberg, who had remained undecided on whom to back in the election, penned an opinion piece addressing the issue of climate change, and announcing he backed President Barack Obama. The reason, he gave, was because the President showed more leadership on the issue than the competitor, Governor Mitt Romney.
“We need leadership from the White House. And over the past four years, President Barack Obama has taken major steps to reduce our carbon consumption, including setting higher fuel-efficiency stands for cars and trucks,” Bloomberg wrote. “His administration also has adopted tighter controls on mercury emissions, which will help to close the dirtiest coal power plants, which are estimated to kill 13,000 Americans a year.”
As the second major storm to hit land in New York City in 14 months, Hurricane Sandy determined Bloomberg’s vote. It caused him to seriously question which president would take the measures necessary to address the growing concern about global warming.
“I want our president to place scientific evidence and risk management above electoral politics,” he wrote.
Across the United States scientists weighed in on whether the hurricane was the result of global warming and whether storms like it would hit coastal areas more frequently in the future. They asked what the necessary measures are to prevent storms like these from causing such debilitating consequences in coastal areas.
And while many concluded that storms like Sandy weren’t directly caused by global warming, many contended that it helped make these storms larger, stronger and more severe. In Canada, the reaction in the scientific community was the same.
In a blog post for Sierra Club Canada, Paul Beckwith, a University of Ottawa Ph.D. candidate in climatology, wrote about what he called Sandy’s “unnatural behavior.”
Beckwith described how as Sandy moved northward off the East Coast, it uncharacteristically shifted left and hit land. Under normal circumstances, the natural progression of a hurricane in the Northern hemisphere that late in the hurricane season would be to move right, because of the tilt of the earth on its access. But a high-pressure system south of Greenland forced it inland, where it merged with a winter storm system moving from the west.
Beckman attributed this “abnormality” to what he called an increase in “nonlinearity events” in global weather patterns, resulting from rising temperatures and melting ice caps.
In short, he said, “global warming.”
The increase in nonlinearity means that weather patterns like the new trajectory of Sandy will become more unpredictable and unprecedented, Beckwith said.
“We’re leaning toward a completely different climate system distinguished by old climate versus new climate. The statistics of weather patterns are completely changing,” Beckwith said. “If you think this storm is bad, get used to it.”
According to scientists with opinions like Beckwith, Sandy was fuelled by surface waters that were roughly 3 C above average along the east coast. A small part of that — roughly 0.6 C — can be attributed to global warming. And while scientists don’t generally attribute one weather event to global warming, they do agree that hurricanes have gotten demonstrably larger in power over the past 20 years.
In an article for the Montreal Gazette, Damon Matthews, a professor in the department of geography at Concordia University and a member of the Global Environmental and Climate Change Center, agreed with Beckwith that rising temperatures cause disruptions in global weather patterns.
“We are living in a new world. The globe is warming, and will continue to do so as long as we continue to fill the atmosphere with greenhouse gases,” Matthews wrote.
“With a warming climate will come increasingly bizarre, and unusual, weather phenomena. Against this backdrop, every strange and bizarre weather event that occurs does so in the context of global warming.”
In an interview, Matthews said that although scientists can’t definitively say Hurricane Sandy was caused by global warming, he said scientists do confirm that violent storms raise serious questions about what lies ahead.
And the storm, he said, was stronger than it should have been because of rising temperatures.
“Every record from every credible source tells us the temperature of the oceans is getting warmer. And it’s making hurricane weather worse.”
In fact, studies published this year suggest that warming due to increasing ice loss in the Arctic Ocean could be changing regional air circulation, causing a more “meandering jet stream.” Researchers say the effect is an increase in the likelihood of severe winter storms and other extreme weather events across the U.S., Europe and northern China.
Leading environmentalist Bill McKibben talks to the Daily Beast on how to talk to climate skeptics?: