Did Climate Change Cause Hurricane Sandy?
This is a short version of a article in Sci American- By Mark Fischetti | Oct, 2012 | Sci. American. Good insight into how a warmer planet does not act alone but has Huge contribution.
If you’ve followed the U.S. news and weather, you have no doubt run across a journalist or blogger explaining why it’s difficult to say that climate change could be causing big storms like Sandy. Well, no doubt here: it is.
Scientists have long taken a similarly cautious stance, but more are starting to drop the caveat and link climate change directly to intense storms and other extreme weather events, such as the warm 2012 winter in the eastern U.S. and the frigid one in Europe at the same time. They are emboldened because researchers have gotten very good in the past decade at determining what affects the variables that create big storms.
Here’s where climate change comes in. The atmospheric pattern that sent the Jet Stream south is colloquially known as a “blocking high”—a big pressure center stuck over the very northern Atlantic Ocean and southern Arctic Ocean. And what led to that? A climate phenomenon called the North Atlantic Oscillation (NAO)—essentially, the state of atmospheric pressure in that region. This state can be positive or negative, and it had changed from positive to negative two weeks before Sandy arrived.
Recent research by Charles Greene at Cornell University and other climate scientists has shown that as more Arctic sea ice melts in the summer—because of global warming—the NAO is more likely to be negative during the autumn and winter. A negative NAO makes the Jet Stream more likely to move in a big, wavy pattern across the U.S., Canada and the Atlantic, causing the kind of big southward dip that occurred during Sandy.
Climate change amps up other basic factors that contribute to big storms. For example, the oceans have warmed, providing more energy for storms. And the Earth’s atmosphere has warmed, so it retains more moisture, which is drawn into storms and is then dumped on us.
These changes contribute to all sorts of extreme weather.
In a recent op-ed in Washington Post, James Hansen at NASA’s Goddard Institute for Space Studies in New York blamed climate change for excessive drought, based on six decades of measurements, not computer models: “Our analysis shows that it is no longer enough to say that global warming will increase the likelihood of extreme weather and to repeat the caveat that no individual weather event can be directly linked to climate change. To the contrary, our analysis shows that, for the extreme hot weather of the recent past, there is virtually no explanation other than climate change.”
Hurricane Sandy has emboldened more scientists to directly link climate change and storms, without the hedge. On Monday, as Sandy came ashore in New Jersey, Jonathan Foley, director of the Institute on the Environment at the University of Minnesota, tweeted: “Would this kind of storm happen without climate change? ‘Yes, Fueled by many factors’. Is the storm stronger because of climate change? ‘Yes.”
Now, as promised: If you still don’t believe scientists, then believe insurance giant Munich Re. Munich Re, one of the world’s largest reinsurance firms, issued a study titled “Severe Weather in North America.” “Nowhere in the world is the rising number of natural catastrophes more evident than in North America.” … While many factors have contributed to this trend, including an increase in the number of people living in flood-prone areas, the report identified global warming as one of the major culprits: “Climate change particularly affects formation of heat-waves, droughts, intense precipitation events, and in the long run most probably also tropical cyclone intensity.”
Let’s remember that the Earth will not cool back for many thousands of years. And it continues to get hotter. So storms will get stronger.
Someone asked me if they should sell their shore home. Of course there are lots of variables including how close you are to the water & elevation, resiliency of your house. But i suggest the biggest issue is: When will the general public make a shift in belief that many shore homes are at risk? And stop buying..