Even worse, records by decade indicate the region has been
consistently drier for the last half-century than it was for a century
before that.
The droughts that have recurred for the last 10 years are a problem, said Hope Mizzell, state climatologist.
"But I think you're staring at a much greater problem."
The wettest decade on record was in the late 1800s, when city of
Charleston rainfall averaged more than 55 inches per year, according to
S.C. Climatology Office graphing of city of Charleston records. Since
1973, the city of Charleston has averaged little more than 44 inches per
year.
While the trend by decade is disturbing, the numbers don't
necessarily signal a climatic shift. Both winter and summer rainfall
patterns are a little drier, not a lot, said Cary Mock, a University of
South
Carolina associate geography professor who has studied climate
trends.
"It's not like we're clearly getting to a drier climate."
But the relatively drier seasons coupled with warming temperatures would bring on more droughts, he said.
Longtime Johns Island farmer Sidi Limehouse has watched it happen.
"I can remember when water never got out of the ditches, the canals.
The canals are now bone dry," he said. The Lowcountry always has cycled
between wet years and dry years, but "the wet cycle is drier than it
was, and the dry cycle is even drier." It used to be you could dig an
irrigation well 20 feet down for water. That water might still be there,
but you can't rely on it. He digs 40 feet now.
The long-soaking winter rains that farmers depend on to grow crops
are evaporating. More and more, it's "dust settlers," in Limehouse's
words -- just enough rain to wet the ground. When a tropical storm
passed offshore in the summer, it dropped 8 inches of rain on the
Limehouse farm -- the sort of soaking that used to leave the ground
mucky for a while. Everything was under water, he said, "and the next
day, it was gone."
Through Wednesday, the official Charleston rainfall since Dec. 1 was
only 1.34 inches, more than 8 inches below normal for the
December-February period considered to be meteorological winter,
according to the National Weather Service, Charleston and the S.C.
Climatology Office. Because a significant rainfall is forecast this
weekend, it's likely this year won't become the worst on record, which
was 1.83 inches in 1949-50.
But the next-lowest "winter" rain record was 2.54 inches, set in
1946-47, so this year is most likely to be at least the second-worst.
The oddest part might be that it hasn't seemed so dry. Unlike the
drought years a few years back, when dry days would run end-to-end for
weeks, rain has fallen. But there have been only 12 days of measured
rain, Mizzell said.
No comments:
Post a Comment