Sunday, May 3, 2015

More Severe Atlantic Hurricanes in Store

We know the oceans are getting warmer. There has been a lot of debate about what this will do in regards to hurricanes, though. The principle reason for this dispute is a lack of data. But, a new study of sediment layers from a Massachusetts salt pond resulted in a record of hurricanes over the years that can be compared to the sea surface temperature record. By analyzing the sedimentary layers they were able to identify severe storms and compiled a record going back 2000 years. They were able to identify 35 severe storms over that period.
At Salt Pond, three coarse grained event beds deposited in the historical interval are consistent with severe hurricanes in 1991 (Bob), 1675, and 1635 C.E., and provide modern analogs for 32 other prehistoric event beds. Two intervals of heightened frequency of event bed deposition between 1400 and 1675 C.E. (10 events) and 150 and 1150 C.E. (23 events), represent the local expression of coherent regional patterns in intense-hurricane–induced event beds. Our synthesis indicates that much of the western North Atlantic appears to have been active between 250 and 1150 C.E., with high levels of activity persisting in the Caribbean and Gulf of Mexico until 1400 C.E. This interval was one with relatively warm sea surface temperatures (SSTs) in the main development region (MDR). A shift in activity to the North American east coast occurred ca. 1400 C.E., with more frequent severe hurricane strikes recorded from The Bahamas to New England between 1400 and 1675 C.E. A warm SST anomaly along the western North Atlantic, rather than within the MDR, likely contributed to the later active interval being restricted to the east coast.
Doing a straight average gives you an average of 1.75 severe storms per century. But, the record shows the storms were not evenly distributed. There were an average of 3.6 severe storms per century from 1400 to 1675 and an average of 2.3 severe storms per century between 150 and 1150. These just happened to be warm periods. In comparison, the remaining 750 years in the record had an average of .28 severe storms per century.

So, when the sea surface temperature was low, there were .28 severe storms per century. When the sea surface temperature was high, there were 2.3 and 3.6 storms per century. Take a look at the sea surface temperature anomaly and draw your own conclusion:

Source: Climate Reanalyzer


2 comments:

  1. What I remember from reading early college, "ecology," text books was how all living things are part of the same web of life. This is not necessarily something mystical or exotic, just the fact that as we ride on this big blue marble, what any one species does is going to have an effect on the rest--like tugging on one portion of a spiders web, and watching the entire web, move in response.


    So if 18% of all species are eradicated, we are facilitating more than just the loss of other species, since their absence cannot help but affect all other forms of life around them---as well as our own! And, if we fail to help preserve these other species, we are going to cause a profound effect on our own.


    The world ecosystem we all live in includes interactions between ourselves and other forms of life. Thus, we won't just lose a large number of other species, but also entire environments that were once suitable to support them--- as well as ours! If we willfully continue to ignore this axiomatic fact, the most we can do is virtually shoot ourselves in the foot, while remaining ignorant of the natural world, which is ultimately a vital home for ourselves as well!

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  2. There is no doubt, if we wipe out 1/6th of the species on the planet, we will regret it. Hopefully, we'll live to regret it, but this is not a given. The planet will survive and life will continue. That does not mean it will include us.

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