Rising Sea Levels: Time for Proactive Action in Florida and the Caribbean? Dr. Alan Fyall and Dr. Thomas Wahl National Center for Integrated Coastal Research, University of Central Florida Dr. Roberta Atzori California State University, Monterey Bay
Climate Change Denial
Fears of immediate sea level rise, which scientists said in the latest IPCC report was accelerating and could mean 75% of the Maldives being under water by 2100, were unfounded it is not going to happen next year. We have immediate needs. Development must go on, jobs are needed, we have the same aspirations as people in the US and Europe
Climate Change the reality
2017 A Catalyst for Change?
The Facts. Globally, mean sea level rise has risen by approximately 1.8 mm/year throughout the 20 th Century In its Fifth Assessment Report, the Intergovernmental Panel on Climate Change (IPCC) determined the likely range (i.e. 66% chance) of global mean sea level rise to be 0.28 m to 0.98 m this Century The National Oceanic and Atmospheric Administration (NOAA) determined that sea level could rise by as much as 2.5 m by 2100
Causes of Sea Level Change Many different processes can cause changes in sea level Some of the observed changes are part of natural climate variability, but most of the observed sea level rise (approximately two thirds) since the 1950s were attributed to anthropogenic impacts Coastal impacts are largest in areas where geocentric (or absolute) sea level rise rates are high AND the land is sinking (for natural or anthropogenic reasons) Land subsidence can lead to relative sea level rise rates at the local scale that are multiple times larger than the global average, or even compared to locations in the vicinity where the land is stable
Sea Level Rise in the Caribbean Torres & Tsimplis (2013) analyzed sea level trends in the Caribbean based on the longest available tide gauge records from sites distributed around the study area Variations evident due to some records covering periods as short as 10 years, so providing less reliable information on long-term sea level rise than others which go back to the early 20 th century
Considerable temporal and spatial variability in the observed sea level trends across the Caribbean Trends vary significantly throughout the region, ranging from only 0.2 mm/yr. (Amuay) to as much as 10.7 mm/yr. (Port Au Prince) This is largely a result of the different record lengths, but also due to vertical land motion that affects some areas more than others Land subsidence is also a contributor to the relative changes between sea level and the land (Glacial Isostatic Adjustment), as are tectonic and human activities and winds and their control on ocean circulation, particularly in the southern part of the Caribbean The longest record at Cristobal shows a long-term trend of 1.9 mm/yr. which is similar to the global average sea level rise over that period Extreme sea levels are most often observed in September/October when tropical cyclones coincide with the peak of the seasonal sea level cycle and spring tides In the Winter season, cold-front passages can also cause sever weather events, including storm surges, typically between January and March Interestingly, currently little or no evidence for significant changes in storminess (frequency and intensity)
In a global study Wahl et al. (2017) recently assessed global storm surges using different statistical models The figure shows the return period of what we currently consider to be a 100-year event (i.e. 1% chance of occurrence in any given year) in 2050 under a moderate sea level rise scenario (RCP4.5) In many places we expect present-day 100 year levels to be exceeded multiple times per decade and in some cases every year
In a similar context, Vitousek et al. (2017) analyzed the factor increase of the probability of what is currently assumed to be a 50-year event due to sea level rise scenarios of 25 and 50 cm Their results highlight strong changes and high vulnerability in the tropics, even for relatively small sea level rise In many tropical regions, the probability that present-day 50-year thresholds are exceeded could increase by factor 175
By the mid-to-late 2000s, over 300 premium resorts will be under severe threat in the Caribbean alone. For the Bahamas, 22% of the host population will be at risk from rising sea levels while in St. Vincent, an estimated 18-30 meters of beach have already been lost to sea level rise.
If business-as-usual continues, by 2060 nine percent of Florida s current land area will be in the zone vulnerable to sea level rise, that is submerged at high tide.
Flooding, inundation of low-lying lands and saltwater intrusion Increased need for engineered shore protection and protection of tourism infrastructure Loss of high-value beaches, changing coastal aesthetics and tourist perceptions of coastal tourism Collapse of coastal eco-system and loss of biodiversity Coastal squeeze (when the coastal margin is squeezed between the fixed inland boundary and the rising sea level) Transformation of coastal tourism (property values, insurance costs, destination competitiveness and marketing) Urgent need for more integrated coastal zone management and planning Changing patterns of tourist visitation (i.e. seasonality, alternative costal and non-coastal destinations)
Responses to Different Climate Change Impacts in Terms of Visitation Intentions I would choose the same destination but different dates (%) I would choose a different destination (%) I would choose the same destination (%) Climate change impacts Temperature becomes uncomfortably hot to me 18.5 65.0 16.4 Rainfall daily duration becomes uncomfortable to me 21.1 57.4 21.5 Cloud cover becomes uncomfortable to me 39.8 45.8 14.4 Wind strength becomes uncomfortable to me 26.4 53.9 19.7 Beaches largely disappear 11.6 14.4 74.1 Corals severely bleach 35.6 21.5 42.8 Marine wildlife largely disappears 31.9 21.8 46.6 Tropical diseases become more widespread 8.8 14.6 76.6 Storms intensify throughout the year 13.0 40.5 46.5 Streets are frequently flooded as a result of rain or tidal surge 10.2 33.1 56.7
Respondents Preferences for Adaptation at the Coastal Destination Adaptation measures Mean Value SD Value Prices of lodging and other products and services are reduced 5.61 1.17 Marine protected areas (sanctuaries) for coastal habitat preservation are created 5.48 1.28 Preservation plans of wetlands flora and fauna are implemented 5.41 1.24 Beach nourishment is implemented to deal with beach shrinking 5.35 1.14 Response plans for coral bleaching are implemented 5.25 1.32 Sea walls defenses and breakwaters are built to avoid beaches/coasts erosion 5.18 1.24 Pumps that draw floodwater from the flooded streets are installed 5.12 1.18 Information about changes in climatic and environmental conditions is provided to visitors 5.00 1.16 Street level is raised to cope with flooding 4.94 1.21 Free transportation to the beach with shuttle buses is provided to visitors 4.91 1.28 Tourism resorts and infrastructure are moved further back from eroding coasts 4.83 1.34 Fans and air conditioning are placed outdoor 4.80 1.48 More indoor leisure-time activities are offered to visitors 4.74 1.22 More built attractions are introduced to replace natural attractions 4.09 1.67
Act collaboratively to sustain tourism for the longer-term benefit of both resident and tourist communities To Avoid. Coastal destinations throughout Florida and the Caribbean should be: Cognizant of the adaptation challenges to be faced and how they will increase with the scale and rate of climate change and sea level rise Understand the impact on seasonality of demand and changing patterns of tourist behavior Prepare realistic destination resilience strategies and curb development that degrades coastal ecosystems Develop proactive social planning, economic recovery and diversification plans
Thank You and Questions alan.fyall@ucf.edu thomas.wahl@ucf.edu ratzori@csumb.edu