1. Sea Level Rise Information
New Smyrna Beach Coastal Community Resiliency Program
Environment and Cultural Resources Session
February 20, 2018
Frank Marshall, PhD PE
Frank Marshall Engineering, PL
Cetacean Logic Foundation, Inc
New Smyrna Beach, FL

2. What is Sea Level Rise (SLR)?
SLR is an increasing trend in the average elevation of the surface of the global oceans over the past 50 years
The two main mechanisms:
thermal expansion of ocean water due to higher temperatures (no additional water mass)
melting of major stores of land ice like glaciers and ice sheets (additional water mass, particularly Arctic and Antarctica ice)
The melting rate and volume of Antarctica ice continues to increase (big time in 2017)
SLR is one of several lines of evidence supporting the hypothesis that the global climate has recently warmed

3. Observed Data: Increase in South Florida Atlantic Ocean Level
Increase = 0.61 ft since 1965
= ft/yr = 0.15 in/yr
KW = ( *date)
Pr > |t| (both terms) = <.0001

4. Local Florida SLR Projections: Southeast Florida Regional Climate Change Compact (2015)
1992 = 0

5. For Other Basic Climate Indicators: What is Expected in the Florida Region by 2050?
from SFWMD (2011) and Regional Climate Change Compact (2015)
Temperature – increase of 1 – 2 degrees C
Rainfall: +/- 5% (-3 to +2 inches)
more heavy precipitation
increase in frequency and duration of dry spells
Evaporation / transpiration: +3 to +6 inches
high uncertainty in evaporation changes
Tropical Storms – fewer but more powerful storms
Increased salinity in coastal water bodies

6. Case Study – 2017 Turnbull Creek Bridge Coastal Hydrology Study

7. Existing Data Were Available for Use
USGS , adjacent to bridge, to
Mean tide range = 1.15 ft
USGS , adjacent to bridge, to
Daily average water elev. = ft NAVD88
Hurricanes Frances and Jeanne (2004) are in this data
FDEP – near USGS , 1983 – 2001
Mean High Water (MHW) = 0.29 ft NAVD88, diurnal range = 0.31 ft
Unusual to have this much information close to project - major cost savings

8. Most Useful Available Data USGS 02248060 monitoring station – adjacent to existing bridge
Hurricane Francis
Hurricane Jeanne

9. Conclusions
Sea level is increasing and forecast to continue doing so according to observed data
Increased temperature, higher evap., fewer but more powerful tropical storms, rainfall = +/- ??
For Florida – best SLR projections for planning purposes: Southeast Florida Regional Climate Change Compact (2015)
Design of Turnbull Creek Bridge (currently under construction) was subject to recent revisions to bridge design guidelines to accommodate:
SLR
Hurricane storm surge and waves from wind