Climate Outlook through 2100 South Florida Ecological Services Office Vero Beach, FL September 9, 2014 Short Term Drought Map: Short-term (<6 mos.) mainly affecting agriculture and grasslands. Figure 1 U.S. Drought Monitor for the Southeast Region (Climate Prediction Center, 2014). Synopsis Florida Conditions remained very dry in the Florida Panhandle during the month of August. By the end of August, the National Weather Service recorded a number of all-time daily high temperature records including: Sarasota, Florida (100 F), Tallahassee, Florida (101 F), and Tampa, Florida (99 F). Some locally heavy rainfall
accumulations (two-to-four inches) were observed in parts of southwestern and northcentral Florida. The Southeast During the first week of August, very heavy rain fell in portions of the southern Mid-Atlantic States contrasted with mostly dry conditions westward. In eastern North Carolina, August 1-5 rainfall topped 5 inches in locations such as Beaufort (6.62 inches) and Cape Hatteras (5.08 inches). However, dryness (D0) and drought (D1) expanded in several areas, particularly in parts of Kentucky, Alabama, Georgia, and northern Florida. By the end of August, the Southeast was hot and generally dry with the exception of some isolated shower activity. According to the National Weather Service, a number of all-time daily high temperature records were broken across the Southeast region including: Montgomery, Alabama (100 F); Sarasota, Florida (100 F); Savannah, Georgia (100 F); Tallahassee, Florida (101 F); and Tampa, Florida (99 F). Continued short-term precipitation deficits and below-normal streamflows worsened drought conditions in Alabama and Georgia. Lake Okeechobee Water Depth Assessment Tool Figure 2 Water Depth Assessment Tool (WDAT) current water depths and wading bird habitat suitability (South Florida Water Management District 1, 2014).
Figure 3 Current Lake levels, management bands, and potential forecast levels based on historical data of warm AMO and El Nino years. (South Florida Water Management District 4, 2014) Everglades South Florida Water Depth Assessment Tool (SFWDAT) Figure 4 South Florida Water Depth Assessment Tool (SFWDAT) with current water depths, muck fire hazards and recession/ascension rates for the Greater Everglades (South Florida Water Management District 1, 2014).
Figure 5 Rain totals for the month. (South Florida Water Management District 3, 2014).
Figure 6 Wet Season rainfall totals present. (South Florida Water Management District 3, 2014).
Hurricane Season 2014: Figure 7 2014 tropical cyclone tracks to date. Forecast from Colorado State University on July 31, 2014: We continue to anticipate a below-average Atlantic hurricane season. While we only expect a weak El Niño to develop this year, conditions in the Atlantic basin appear especially detrimental for hurricane formation. Atlantic Main Development Region sea surface temperatures are cooler than normal, sea level pressures are higher than normal, and vertical wind shear throughout the Atlantic basin has been much stronger than normal. Landfall probabilities for both the United States and Caribbean are below their long-period average values. JULY 31, 2014 - ATLANTIC BASIN SEASONAL HURRICANE FORECAST FOR 2014: Storm Type Average Annual Current Forecast Tropical Storm 12 10 Hurricane 7 4 Major Hurricane 2 1 Major Hurricane Landfall Chances after July 31 37% 14% Table 1 July 31, 2014 Atlantic Basin Seasonal Hurricane Forecast for 2014. (Klotzbach, 2014) The next quantitative forecast will be August 14, 2014.
ENSO Status (El Nino Watch in effect): During August 2014, above-average sea surface temperatures (SST) continued across much of the equatorial Pacific. Subsurface heat content also increased during the month However there is a lack of a coherent atmospheric El Niño response which indicates a continuation of ENSO-neutral at this time. Most of the models continue to predict El Niño to develop during September-November and to continue into early 2015. A majority of models and the multi-model averages favor a weak El Niño with a 60-65% likelihood during the fall and winter. The following ENSO indicators were observed last month: Sea surface temperatures Warmer than average (+3 C). (El Nino) Sub-surface temperatures (0-100m depth) Warmer than average (+2 C). (El Nino) Southern Oscillation Index (measure of air pressure between Tahiti and Darwin, Australia) = -9.7. Normal ranges are +8 to -8. Sustained values below -8 indicate the development of El Nino. (El Nino) Trade Winds (equatorial Pacific Ocean) near average. If trade winds are sustained lower than average, it indicates the development of El Nino. (Neutral) Cloudiness (at the equator near the Date Line) Average. (Neutral) El Nino Conditions ENSO-Neutral La Nina Conditions Figure 8 Sea Surface Temperatures (SST) for Nino 3.4 region of the Pacific Ocean (Australian Government - Bureau of Meteorology, 2014)
El Nino Conditions ENSO Neutral is ±.5 C La Nina Conditions Figure 9 - All climate model runs. (Climate Prediction Center, 2014) Figure 10 Latest probabilities of an El Nino development during the Fall 2014. (Climate Prediction Center, 2014)
Expected ENSO effects for Florida include: Decreased Atlantic Ocean hurricanes in 2014 Wetter than normal dry season (2014-2015) Above average surface water elevations for the dry season (2014-2015) Fewer fires with smaller burn areas for the dry season (2014-2015) Colder winter (2014-2015) than average Central & South Florida Temperature Outlook: September warmer than average October thru December average January 2015 cooler than average February thru March 2015 much cooler than average April 2015 cooler than average May 2015 average June through August 2015 warmer than average Central & South Florida Rainfall Outlook: September thru December wetter than average January thru March 2015 much wetter than average April 2015 wetter than average May thru August 2015 - average Projections through 2023: The Atlantic Multi-decadal Oscillation (AMO) The AMO occurs in warm and cool phases lasting 20-40 years each generally. Florida typically experiences wetter conditions during the warm phase as the Inter-tropical Convergence Zone (ITCZ) moves farther north closer to Florida from the equator. The ITCZ is a global band of convective thunderstorms occurring 10-20 degrees north and south of the equator. Other than the local weather drivers and ENSO, the AMO highly influences Florida s extended wet and dry trends. Historical and Current Conditions: Since 1900, there have been two cool phases and two warm phases of the AMO with each of these phases lasting 20-40 years each (see Table 1). The exact year of the phase start and finish is an estimate as each phase goes through a transition period of a few years. Table 2 1906 1926 = 20 years (cool phase) 1927 1965 = 38 years (warm phase) 1966 1992 = 26 years (cool phase) 1993 Present = warm phase Table 2 Timing and duration of cool and warm AMO phases since 1900. The warm phase of the AMO is expected to continue to around the year 2020. Thus, wetter overall conditions with active hurricane seasons can be expected. Around 2020, the AMO will go through a transition period. Afterwards, we will be in for a 20-25 year period of drier conditions and inactive hurricane seasons (Miller, 2010).
Projections through 2100 (U.S. Global Change Research Program, 2013): Projections are based on the A2 climate model scenario which assumes high emissions of heattrapping gases continue to rise. In this scenario, concentrations of atmospheric CO₂ exceed 800 ppm by the year 2100. Today s atmospheric CO₂ concentrations are around 400 ppm. Surface temperatures will increase. Length of freeze-free days will increase by 20-30 days. Rainfall in central and southern Florida: Winter - will increase by 20%. Spring - will increase by 5-10% for the Kissimmee basin, but decrease by 5% in southern Florida. Summer will decrease by 10% for the Kissimmee basin and decrease by 15% in southern Florida. Fall will increase by 5% for the Kissimmee basin and decrease by 5% in southern Florida. Lori Miller FWS Hydrologist - 772.469.4231 (Lori_miller@fws.gov) Works Cited Australian Government - Bureau of Meteorology. (2014). Climate and Past Weather. Retrieved from Australian Government - Bureau of Meteorology: http://www.bom.gov.au/climate/enso/ Climate Prediction Center. (2014). Retrieved from Climate Prediction Center: http://www.cpc.ncep.noaa.gov/index.php Drought Reporter. (2014). Drought Reporter. Retrieved from Drought Reporter: http://droughtreporter.unl.edu/ Klotzbach, P. a. (2014). QUALITATIVE DISCUSSION OF ATLANTIC BASIN SEASONAL HURRICANE ACTIVITY FOR 2013. Fort Collins, CO: Department of Atmospheric Science, Colorado State University. Miller, L. (2010). Climate of South Florida; Everglades Restoration Transition Plan Phase I Biological Opinion. Vero Beach, Florida: U.S. Fish and Wildlife Service. South Florida Water Management District 1. (2014). South Florida Water Depth Assessment Tool (SFWDAT) - Everglades Implementation. Retrieved from South Florida Water Depth Assessment Tool (SFWDAT) - Everglades Implementation: http://my.sfwmd.gov/kmlext/customkmls/sfwdat/everglades/output/a nimations/animation365.html South Florida Water Management District 2. (2014). Water Depth Assessment Tool (WDAT) - Lake Okeechobee. Retrieved from http://my.sfwmd.gov/kmlext/customkmls/sfwdat/okeechobee/output/a nimations/animation365.html South Florida Water Management District 4. (2014). Operational Planning. Retrieved 2014, from South Florida Water Management District:
http://www.sfwmd.gov/portal/page/portal/xweb%20- %20release%202/operational%20planning#position_analysis South Florida Water Management District 3. (2014). Weather and Water. Retrieved from Weather and Water: http://www.sfwmd.gov/portal/page/portal/levelthree/weather%20%20water U.S. Army Corps of Engineers. (2014). SAJ Water Management Graphical Plots. Retrieved from SAJ Water Management Graphical Plots: http://w3.saj.usace.army.mil/h2o/plots.htm U.S. Global Change Research Program. (2014). National Climate Assessment. Washington D.C.: National Oceanic and Atmospheric Administration (NOAA).