Jim_OBrien by pengxiang

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									Global Climate Change in Florida?
The Truth about Climate Change
 in the Southeast United States
                         By
                 Dr. James J. O’Brien
                   Retired Emeritus
       Robert O. Lawton Distinguished Professor
           Meteorology and Oceanography
      SUBTITLE
WHAT AL GORE AND HIS
    FOLLOWERS
 WILL NOT TELL YOU
What if sea level rose 6 meters?




Image courtesy of Environmental Studies Laboratory,
University of Arizona
LETS TALK ABOUT
   ORANGES
   SEALEVEL
  SE COOLING
  HURRICANES
THE ORANGE STORY
                Climate and Florida Citrus
           Adapted from: John Attaway, “A History of Florida
                           Citrus Freezes”
                  Impact
                  Freezes:
                  February     7-9,
                  1835
                  December     29,
                  1894
                  February       8,
                  1895
                  February     13-
                  14, 1899
                  December 12-
                  13, 1934
                  January 27-19,
Freeze damaged orange trees in 1895
                  1940
                  December 12-
                  13, 1962
                  January 18-20,
  “The Warm Century” – prior to 1835




                              Mature orange grove
                              outside of St. Augustine,
                              FL in the early 1890’s.
                              Trees have obviously
Citrus was introduced with    grown for decades without
success at colonial           major freeze damage. -
Charleston, Savannah, and     from Buel, 1893
St. Augustine. Accounts are
Orange Industry takes hold in North-
          Central Florida
                   The freeze of 1835 killed
                   trees to the roots in South
                   Carolina, Georgia, and
                   northeast Florida with
                   temperatures reaching as
                   low as 1 degree F in
                   Charleston.

                   Following this event, a
                   thriving orange industry
                   sprang up in Alachua,
                   Marian and Putnam
                   counties surrounding
                   Orange Lake.
Center of Production Moves to
Central Florida – 20th Century
                 The winter of 1894/1895
                 experience two severe
                 freezes (mid-Dec. and
                 mid-Feb.) separtated by
                 an unusually warm spell.

                 Groves damaged by the
                 Dec. freeze had produced
                 tender new vegetation
                 prior to the Feb. event,
                 leaving them especially
                 vulnerable.

                 Damage by these freezes
Present Day – Citrus moves
      further South

             Beginning in 1977 and
             lasting through 1989,
             Florida saw a succession
             of severe freezes that
             damaged trees further
             south than ever before.
             The center of production
             moved further south to its
             present position in west-
             central and southwest
             Florida.
             The more tropical climate
The Sea Level Story
What if sea level rose 6 meters?




Image courtesy of Environmental Studies Laboratory,
University of Arizona
Local sea level measurements



                         Key West
                         2.27 mm/yr




                          Pensacola
                          2.14 mm/yr
                           Sea Level Rise

• Global Measurements from Tide Gauges:
  2.1 mm/year = 8.4 in/century
• Global Measurement from Altimeter:
  3.1 mm/year = 12.4 in/century
• There is no acceleration observed
• Al Gore says 20 feet sometime
• At current rate, 5 feet will take 484 years
• At double current rate, 5 feet in 242 years
• At quadruple rate, 5 feet in 141 years
• The pertinent question for Florida is not will sea level rise but
  will storms get stronger
Historic sea level rise

            • Sea level measurements from
              23 highest quality tidal stations
              around the world.

            • Estimates of sea level rise from
              1 mm/yr to 2 mm/yr.

            • Satellite measurements
              (altimeters) since 1992 indicate
              a rise of around 3mm/yr.

            • IPCC third assessment report
              stated "No significant
              acceleration in the rate of sea
              level rise during the 20th century
              has been detected."
THE FLORIDA TEMPERATURE
         STORY
  MOST RURAL STATIONS ARE COOLING 2-4 F/CENTURY
A Closer Look – De Funiak Springs


                • Town is located to the northeast
                  of Eglin AFB, a large expanse of
                  undeveloped forests.
                • Surrounding countryside consists
                  of pastures, farmland, and pine
                  forests.
                • Station located at Showel Farms,
                  3 miles to the east of the city.
                • Walton County population is very
                  low at around 40,000.
                • USHCN station (unadjusted data)
A Closer Look – De Funiak Springs
A Closer Look – Arcadia


           • Small Town surrounded by
             pastures, citrus groves, pine
             stands, and lowlands.
           • Station located at the water
             treatment plant inside the city
             limits.
           • Arcadia has grown very little in
             the last 40 years and only has a
             population of around 10,000.
           • USHCN station (unadjusted data)
A Closer Look – Arcadia
A Closer Look – Fort Myers

             • Station located at Page Field
               near downtown Fort Myers.
             • The city of Fort Myers has
               experienced tremendous urban
               sprawl in the last 40 years.
             • Lee county population has
               ballooned from 60,000 to over a
               half million in the last 40 years.
             • USHCN station (unadjusted data)
A Closer Look – Fort Myers
A Closer Look – Belle Glade


             • Small Farming community near
               the southern shore of Lake
               Okeechobee.
             • Station located 2.5 miles south
               of town at the Agriculture
               Experiment Station.
             • Relatively stable population.
             • USHCN station (unadjusted
               data)
             • Data record SHOULD be
               reflective of predominant climate
               trends.
A Closer Look – Belle Glade
                Wrong!!! – Land Use Change
                                 Land cover maps of Florida from the pre-
                                 1900’s and from 1993 show the area
                                 south of Okeechobee now surrounded by
                                 irrigated sugar cane fields.




Mesoscale modeling has
shown large summertime
temperature differences in the
area from differences in land
use (Marshall, et al., 2004).
                                   Temperature difference in degrees C
THE HURRICANE STORY
Probability of Hurricane Landfall: U.S. Coast
25-Year Period Signal + Trend               2-Year Period Signal + Trend




                       Smoothed Time Series
                              Tyr1  2  Tyr  Tyr1
                     T yr 
                                        4
2-Year Period + 25-Year Period Signals + Trend




            Smoothed Time Series
Bonus material
               A GIFT
                SEE
http://coaps.fsu.edu/gis/decile.php
Probability of extreme
Temperatures in USA
Change in Beginning of the Hot Season
Change in End of the Hot Season
Change in Length of the Hot Season
THE END

QUESTIONS PLEASE

								
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