Florida Climate Outlook: Assessing Physical and Economic Impacts through 2040

The Florida Climate Outlook takes a novel, visual approach in synthesizing new and existing research on Florida’s climate future in the next 20 years. Based on plausible emissions and sea level rise scenarios, the authors assess the physical and economic impacts of climate change—including its effects on storms, human mortality, and agriculture—along with the economic impacts national climate policies would have on Florida households. Throughout the report, infographics illustrate the findings, highlighting key impacts and considerations. For an easy-to-print copy of these infographics, download the document below; read the full report (above) for the full context and references behind these graphics.

This work was supported by the VoLo Foundation. The authors would like to thank Kevin Rennert and Marc Hafstead at Resources for the Future for helpful feedback and economic modeling input and the Climate Impact Lab for their work, which underlies several of the findings in this report. Any errors are the responsibility of the authors.

Climate change is affecting Florida today, and those effects will become more significant in the years to come. This introduction provides basic information on recent temperature trends in Florida, along with projections over the next 20 years. This report discusses the implications of these changing temperatures along with changes in other climatic conditions that will affect Floridians. The report addresses the following topics:

• Effects of Sea Level Rise in Florida
• Effects of Climate Change on Storms in Florida
• Effects of Climate Change on Human Mortality in Florida
• Effects of Climate Change on Agriculture in Florida
• Impacts of National Climate Policies on Florida Households

We examine these effects under two plausible scenarios: a moderate emissions scenario, where global greenhouse gas emissions rise by roughly 1 percent annually over the next 20 years; and a high emissions scenario, where emissions rise by 3 percent annually. These scenarios are drawn from an extensive literature and correspond with climate scenarios known as Representative Concentration Pathways (RCP) 4.5 and 8.5. We apply similar scenarios for future sea level rise. For details on these scenarios, and our rationale for selecting them, please see the Appendix.

Historical and Projected Temperature Trends in Florida

Summer temperatures in Florida have increased by roughly 1°F since 1950, averaging 81.4°F from 1991 to 2010. In the next 20 years, average summer temperatures are projected to rise above 83°F under both moderate and high emissions scenarios.[1,2] There is more uncertainty surrounding future temperatures under a high emissions scenario than under a moderate emissions scenario.

From 1981 to 2010, Floridians experienced, on average, high temperatures exceeding 95°F roughly 7 days per year. Under moderate and high emissions scenarios, this number is projected to grow to 22 and 26 days per year, respectively. [1]

From 1950 to 1970, winter temperatures in Florida averaged 57.4°F. In the following decades, temperatures rose by more than 2°F, averaging 59.5°F between 1991 and 2010. In the next 20 years, average winter temperatures are projected to rise above 60°F under both moderate and high emissions scenarios. [1,2]

Introduction References

1. Climate Impact Lab. Climate Impact Map. (2019).
2. Southeast Regional Climate Center. Monthly and Seasonal Climate Information. https://sercc.com/climateinfo/monthly_seasonal. (2019).

Overview

Climate change raises sea levels by increasing ocean temperatures (which causes water to expand) and by melting glaciers and ice sheets (which adds water to the oceans). Global sea levels have risen by an average of about 8–9 inches since 1880, and climate change is projected to further accelerate sea level rise. Church, J. A. et al. Sea level change, Chapter 13. in Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (Cambridge University Press). Before land is permanently submerged, rising seas will lead to higher and more frequent coastal flooding.

Florida’s long coastline and low-lying land make it particularly vulnerable to the damaging impacts of sea level rise. Every additional inch of sea level rise will increase the economic risks Florida faces from flooding, which will threaten more property and infrastructure. Rising seas will also reduce groundwater quality through saltwater intrusion.

The effects of higher sea levels are being felt today, with major implications for Florida communities. For example, a recent analysis by the Monroe County Sustainability Office highlights the large costs of raising public roadways to accommodate higher sea levels by 2045. Haag, R. Climate Change & Sea Level Rise in the FL Keys: Monroe County Begins to Bridge the Gap. Presented at the Monroe County 11th Annual Climate Leadership Summit. https://www.monroecounty-fl.gov/DocumentCenter/ View/22097/Summit-2019-Haag-Presentation-FINAL (2019). Because of these costs, it is unlikely that the county will be able to protect all roads in the Keys, suggesting that some roads and neighborhoods will need to be abandoned. Flavelle, C. & Mazzei, P. Florida Keys Deliver a Hard Message: As Seas Rise, Some Places Can’t Be Saved. The New York Times. https://www.nytimes. com/2019/12/04/climate/florida-keys-climate-change.html (2019).

This section examines the projected effects of sea level rise using three scenarios: a moderate scenario defined by 0.5 meters (1.6 feet) of additional In this section, additional sea level rise is relative to the average level between 1986 and 2005 global sea level rise by 2100; a higher scenario defined by 1 meter (3.3 feet) by 2100; and an extreme scenario defined by 2.5 meters (8.2 feet) by 2100. For a more detailed description of these scenarios, and their likelihoods under different emissions pathways, see Appendix A.

Key Findings

• Globally, the median projection for additional sea level rise by 2040 is roughly 7 inches under the moderate scenario, 10 inches under the higher scenario, and 16 inches under the extreme scenario. Sweet, W. V. et al. Global and Regional Sea Level Rise Scenarios for the United States. https://tidesandcurrents.noaa.gov/publications/techrpt83_Global_ and_Regional_SLR_Scenarios_for_the_US_final.pdf (2017).
• Because of wind and ocean circulation patterns, Florida has historically experienced higher rates of sea level rise than the global average.5 This trend is expected to continue, with estimates varying for different locations along the Florida coast. By 2040, under the moderate scenario, median projections of sea level rise at different points along Florida’s coastline range from 8–9 inches. Under the higher scenario, median projections are between 12 and 13 inches, and under the extreme scenario, median projections are approximately 24 inches. Sweet, W. V. et al. Global and Regional Sea Level Rise Scenarios for the United States. https://tidesandcurrents.noaa.gov/publications/techrpt83_Global_ and_Regional_SLR_Scenarios_for_the_US_final.pdf (2017).
• There is uncertainty around these projections, even under a given scenario. For example, by 2040 at St. Petersburg, there is a two-thirds probability of sea level rise between 7 and 11 inches under the moderate scenario, 11 and 15 inches under the higher scenario, and 17 and 26 inches under the extreme scenario. There is a one-third probability that sea level rise will be either lower or higher than these ranges under a given scenario. Projections for other coastal locations include similar ranges of uncertainty. Sweet, W. V. et al. Global and Regional Sea Level Rise Scenarios for the United States. https://tidesandcurrents.noaa.gov/publications/techrpt83_Global_ and_Regional_SLR_Scenarios_for_the_US_final.pdf (2017).

• By 2100, averaging across coastal locations in Florida, scientists expect to see additional sea level rise of roughly 2, 4, and 10 feet under moderate, higher, and extreme sea level rise scenarios. Sweet, W. V. et al. Global and Regional Sea Level Rise Scenarios for the United States. https://tidesandcurrents.noaa.gov/publications/techrpt83_Global_ and_Regional_SLR_Scenarios_for_the_US_final.pdf (2017) Four feet of sea level rise could submerge up to 2,400 square miles of land in Florida, including large portions of densely populated coastal regions.
• Several major tourist attractions, including the Everglades, Biscayne National Park, and Miami Beach, are largely situated on land less than three feet above the high-water mark In this section, “high-water mark” refers to the mean higher high water measurement from 1983 to 2001. “Mean higher high water mark” represents the average of the highest water mark during each tidal day over the reference period. and may become permanently submerged by the end of the century. In the coming decades, they are particularly at risk from flooding and saltwater intrusion.

• Before land is permanently submerged, higher sea levels will bring more frequent and higher floods through the direct effects of tidal inundation and storm surge. Higher sea levels can also indirectly increase the severity of flooding by raising the groundwater level. This phenomenon decreases the capacity of the soil to help with drainage, resulting in floodwaters remaining higher for longer periods of time.
• All along Florida’s coast, the annual risk of flooding is projected to increase substantially. Extreme flooding that previously would have been expected to occur just once every 100 years (a “100-year” flood), with waters reaching 2–3 feet above the high-water mark depending on the specific location, will become more frequent (Table 1).
• This level of flooding would cause large damages. Statewide, roughly 490,000 people live on land less than 3 feet above the high-water mark, with over 300,000 homes and an estimated $145 billion in property value. Over 2,500 miles of roads, 372 hazardous waste sites, 30 schools, and 4 hospitals could be subjected to flooding. The counties with the largest number of people facing this risk are Miami-Dade, Broward, Pinellas, Monroe, and Hillsborough. Climate Central. Sea level rise and coastal flood exposure in Florida: Original population, buildings, and roads data from US Census; hazardous waste site data from EPA; school data from NTIA; hospital data from BGN/USGS; property value data from Neumann et. al. https://riskfinder.climatecentral.org/ (2014). Neumann, J., Herter, D. & Martinich, J. The economics of adaptation along developed coastlines. Wiley Interdisciplinary Reviews: Climate Change 2, 89–98 (2010).
• Through 2040, the risk for even higher flooding is greatest on the western side of Florida, from the Tampa Bay area through the Panhandle (Table 2). In future decades, as sea levels rise further, other parts of the state with greater populations, such as southeast Florida, will also face higher risks of flooding.
• From Tampa Bay through the Panhandle, the area most at risk by 2040, there are roughly 290,000 people living on land less than 5 feet above the high-water mark, with over 200,000 homes. Climate Central. Sea level rise and coastal flood exposure in Florida: Original population, buildings, and roads data from US Census; hazardous waste site data from EPA; school data from NTIA; hospital data from BGN/USGS; property value data from Neumann et. al. https://riskfinder. climatecentral.org/ (2014).
• As sea levels rise, ocean water will continue to move farther inland into freshwater aquifers in a process known as saltwater intrusion, posing a contamination threat to drinking water and agriculture. Particularly at risk is the Biscayne aquifer, located under Miami-Dade County, which provides drinking water to around 4.5 million people. Marella, R. L. Water Withdrawals, Use, and Trends in Florida, 2005. https://pubs.usgs.gov/sir/2009/5125/pdf/sir2009-5125.pdf (2009).
• Saltwater intrusion also poses a unique threat to inland ecosystems such as forests and freshwater wetlands, which are not accustomed to higher levels of salinity. Tully, K., Epanchin-Niell, R. & Strong, A. The Invisible Flood: The Chemistry, Ecology, and Social Implications of Coastal Saltwater Intrusion. BioScience 69, 368–378 (2019).

Overview

More than any other US state, Florida is susceptible to damages from tropical storms, and climate change is projected to increase these risks. Over the last 1,000 years, periods with higher global temperatures have corresponded with a larger number of intense hurricanes making landfall in the state, Ercolani, C., Muller, J., Collins, J., Savarese, M. & Squiccimara, L. Intense Southwest Florida hurricane landfalls over the past 1000 years. Quaternary Science Reviews 126, 17–25 (2015). and higher future air and water temperatures are projected to increase the severity of tropical storms, leading to higher storm surges (the rise in water levels above normal tides due to storms), faster wind speeds, and greater volumes of precipitation. Payne, E. J. et al. Coastal Effects. in Impacts, Risks, and Adaptation in the United States: Fourth National Climate Assessment, Volume II (eds. Reidmiller, D. R. et al.) 322–352 (US Global Change Research Program, 2018).

The most severe property damage from tropical storms is typically caused by storm surges. Damages from a single hurricane can total tens of billions of dollars from storm surge alone, putting unprotected areas at particularly high risk. Genovese, E. & Green, C. Assessment of storm surge damage to coastal settlements in Southeast Florida. Journal of Risk Research 18, 407–427 (2015). Although many communities have prepared for a certain level of surge, small increases above that preplanned level can lead to a large increase in damages, with a disproportionate increase in flooded buildings, as well as disruption of evacuation routes. Helderop, E. & Grubesic, T. H. Hurricane storm surge in Volusia County, Florida: evidence of a tipping point for infrastructure damage. Disasters 43, 157–180 (2019).

More severe storms not only pose risks to human lives and prosperity, they also reduce regional economic output over the short and long term. Hsiang, S. M. & Jina, A. S. The Causal Effect of Environmental Catastrophe on Long-Run Economic Growth: Evidence From 6,700 Cyclones. http://www.nber.org/papers/w20352 (2014) doi:10.3386/w20352.

Key Findings

• Miami is one of the most at-risk cities in the world from the damages caused by coastal flooding and storms. By one measure, it faces the largest risk of any major coastal city in the world, with more than $400 billion in assets at risk as of 2005. Hanson, S. et al. A global ranking of port cities with high exposure to climate extremes. Climatic Change 104, 89–111 (2011).
• Under a moderate emissions scenario,a Note: “Moderate emissions scenario” refers to RCP 4.5. “High-end projections” refers to the 95th percentile of modeled scenarios. See Appendix A for details. by 2100, the combined effects of sea level rise and greater storm intensity are projected to increase the height of storm surges in Florida by 25–47 percent compared with storm surges from hurricanes between 1984 and 2013. High-end estimates show storm surges rising 40–70 percent above historic levels. Balaguru, K., Judi, D. R. & Leung, L. R. Future hurricane storm surge risk for the U.S. gulf and Florida coasts based on projections of thermodynamic potential intensity. Climatic Change 138, 99–110 (2016).
• Adaptation measures include beach nourishment, wetlands restoration, “hard” protective barriers, and elevation of structures. However, projections through the year 2100 suggest that in some parts of Florida, such as East Tampa Bay, sea level rise combined with the effects of storm surges will make such protections very expensive. Modeling suggests that in such cases, the most economically viable option will be to abandon substantial areas of currently inhabited land. Neumann, J. E. et al. Joint effects of storm surge and sea-level rise on US Coasts: new economic estimates of impacts, adaptation, and benefits of mitigation policy. Climatic Change 129, 337–349 (2015).
• Florida cities are investing to protect against these risks, such as Miami Beach’s $500 million effort to protect buildings, roads, and water systems. Such investments can dramatically reduce the damages to property and risks to human life from sea level rise and storm surges. Neumann, J. E. et al. Joint effects of storm surge and sea-level rise on US Coasts: new economic estimates of impacts, adaptation, and benefits of mitigation policy. Climatic Change 129, 337–349 (2015).Bakkensen, L. A. & Mendelsohn, R. O. Global Tropical Cyclone Damages and Fatalities Under Climate Change: An Updated Assessment. in Hurricane Risk (eds. Collins, J. M. & Walsh, K.) 179–197 (Springer International Publishing, 2019). doi:10.1007/978-3-030-02402-4_9.

• Warmer ocean temperatures are projected to contribute to higher hurricane windspeeds. One study estimates that damages from these higher windspeeds alone would result in roughly $200 million in additional annual storm damages for buildings in Miami-Dade County by 2035. Pant Sami & Cha Eun Jeong. Effect of Climate Change on Hurricane Damage and Loss for Residential Buildings in Miami-Dade County. Journal of Structural Engineering 144, 04018057 (2018).
• Other types of severe weather, such as severe thunderstorms that produce damaging hail or tornadoes, may also become more harmful as a result of climate change. However, there is substantial uncertainty surrounding this issue, and researchers are currently working to better understand the topic. Kossin, J. P. et al. Extreme Storms. in Climate Science Special Report: Fourth National Climate Assessment, Volume I (eds. Wuebbles, D. J. et al.) 257–276 (U.S. Global Change Research Program, 2017).

Overview

As the climate changes, shifts in temperature, precipitation, sea levels, and other physical drivers have the potential to affect human health in a variety of ways. Extreme temperatures can directly affect mortality rates when the physiological response to heat or cold (e.g., increased heart rate) endangers wellbeing, particularly through cardiovascular, cerebrovascular, and respiratory pathways. Song, X. et al. Impact of ambient temperature on morbidity and mortality: An overview of reviews. Science of The Total Environment 586, 241–254 (2017).

Studies consistently find that increased exposure to extreme heat or cold is associated with higher rates of cardiovascular-related mortality. Climate change is also likely to indirectly affect human health through changing patterns of disease vectors (i.e., mosquitoes and other organisms that can transmit diseases), extreme weather, human conflict, and other environmental or socioeconomic pathways. U.S. Census Bureau. The Nation’s Older Population Is Still Growing, Census Bureau Reports. https://www.census.gov/newsroom/press-releases/2017/ cb17-100.html (2017).

Because Florida is warmer than most US states, its residents already experience risks from heat and—compared with the rest of the US—relatively little risk associated with cold. This dynamic will be enhanced as average temperatures increase as a result of climate change. Because the average age in Florida is higher than in most other states,2 its population is particularly vulnerable to these risks. Anderson, B. G. & Bell, M. L. Weather-Related Mortality: How Heat, Cold, and Heat Waves Affect Mortality in the United States. Epidemiology 20, 205–213 (2009).

Key Findings

• Within the next 15–20 years, the median estimates under moderate and high emissions scenarios The estimate of additional deaths in 2035 is based on population projections for the year 2035 and assumes no demographic changes from 2012 to 2035. “Moderate emissions scenario” refers to RCP 4.5, and “high emissions scenario” refers to RCP 8.5. “Low- and high-end estimates” refers to the 5th and 95th percentile estimates from Hsiang et al. under both RCP 4.5 and RCP 8.5 scenarios. project respective increases in the rate of mortality of 3.8 and 5.6 per 100,000 Florida residents per year. Hsiang, S. et al. Estimating economic damage from climate change in the United States. Science 356, 1362 (2017) These estimates translate to roughly 1,000 and 1,400 additional deaths annually by 2035 and would mostly affect those older than 65.
• There is substantial uncertainty surrounding these median estimates. Low- and high-end statewide estimates in 2035 range from a decrease of 2.1 to an increase of 12.8 deaths per 100,000 residents per year. Hsiang, S. et al. Estimating economic damage from climate change in the United States. Science 356, 1362 (2017) This is equal to between 540 fewer deaths and 3,200 additional deaths in Florida in the year 2035. Decreased mortality is possible because of reduced exposure to cold temperatures.
• Charlotte, Martin, Monroe, Palm Beach, and Hernando Counties face the greatest risk. Under a moderate emissions scenario, the central estimate for these counties is an increase in annual mortality rates of more than 6 deaths per 100,000 residents. Under a high emissions scenario, the central estimate for Hernando and Charlotte Counties is greater than 9 additional deaths per 100,000 residents annually. Hsiang, S. et al. Estimating economic damage from climate change in the United States. Science 356, 1362 (2017).

• In absolute terms, the largest number of excess deaths is projected to occur in heavily populated southeastern counties. Under moderate and high emissions scenarios, the median estimates for annual excess deaths in 2035 are respectively 175 and 191 for Miami-Dade, 110 and 128 for Broward, and 99 and 119 for Palm Beach Counties. Hsiang, S. et al. Estimating economic damage from climate change in the United States. Science 356, 1362 (2017).
• More modest effects are projected for northern Florida. However, median estimates project increased mortality due to temperature change in every Florida county. Under a moderate emissions scenario, the smallest risks are seen in Liberty, Bay, and Gulf Counties, though median estimates show mortality rates increasing by more than 0.5 per 100,000 residents in these counties. Hsiang, S. et al. Estimating economic damage from climate change in the United States. Science 356, 1362 (2017).
• There is a substantial range of uncertainty for all counties. For example, low- and high-end estimates for Miami-Dade County range from 65 fewer deaths to 420 additional deaths per year by 2035. Hsiang, S. et al. Estimating economic damage from climate change in the United States. Science 356, 1362 (2017). Fewer deaths could occur because of reduced exposure to cold temperatures.
• Disease risk from mosquito-borne viruses (particularly Aedes aegypti, which can spread dengue, chikungunya, and Zika) is projected to become a year-round phenomenon in southern Florida. Carter, L. et al. Southeast. in Impacts, Risks, and Adaptation in the United States: Fourth National Climate Assessment, Volume II (eds. Reidmiller, D. R. et al.) 743–808 (U.S. Global Change Research Program, 2018). Florida residents are already at risk of exposure to West Nile virus, a trend that is projected to persist under climate change. Harrigan, R. J., Thomassen, H. A., Buermann, W. & Smith, T. B. A continental risk assessment of West Nile virus under climate change. Global Change Biology 20, 2417–2425 (2014).
• Recent peer-reviewed studies have examined other factors that may increase mortality in Florida. Quantitative estimates for these effects are not available for Florida specifically, but the findings suggest increased risks from energy supply disruptions, Larsen, K., Larsen, J., Delgado, M., Herndon, W. & Mohan, S. Assessing the Effect of Rising Temperatures: The Cost of Climate Change to the U.S. Power Sector. 27 https://rhg.com/wp-content/uploads/2017/01/RHG_ PowerSectorImpactsOfClimateChange_Jan2017-1.pdf (2017). suicide, Burke, M. et al. Higher temperatures increase suicide rates in the United States and Mexico. Nature Climate Change 1 (2018) doi:10.1038/s41558- 018-0222-x. and wildfire. Carter, L. et al. Southeast. in Impacts, Risks, and Adaptation in the United States: Fourth National Climate Assessment, Volume II (eds. Reidmiller, D. R. et al.) 743–808 (U.S. Global Change Research Program, 2018).

Overview

Climate change will have varying effects on Florida’s agricultural sector. Some of the state’s most valuable agricultural products will be at increased risk of damages due to climate change, while some of its less important crops may benefit somewhat from a changing climate and atmosphere.

Florida’s most valuable agricultural products include fruits—particularly citrus—and vegetables; livestock and dairy; and a variety of greenhouse, nursery, and mushroom products. US Bureau of Economic Anlaysis. Regional Data: GDP and Personal Income. https://apps.bea.gov/iTable/index_regional.cfm (2019). Florida farmers produce more than half of all the oranges and grapefruits grown in the United States. Florida Department of Agriculture and Consumer Services. Florida Agriculture Overview and Statistics. https://www.freshfromflorida.com/ Agriculture-Industry/Florida-Agriculture-Overview-and-Statistics (2019). However, these crops have recently come under threat from “citrus greening” (also known as Huanglongbing, or HLB), a disease that reduces a tree’s ability to absorb nutrients, decreasing yields and typically leading to tree death within several years. United States Department of Agriculture, Animal and Plant Health Inspection Service. Citrus Greening. https://www.aphis.usda.gov/aphis/resources/pests-diseases/hungry-pests/the-threat/citrus-greening/citrus-greening-hp (2019).

Although Florida is a major producer of certain agricultural products, the overall sector accounted for just 0.6 percent of state gross domestic product in 2017, down from 1.2 percent in 2000.1 The sector is not a major employer in the state, with just 0.2 percent of Florida’s workforce employed in farming, fishing, and forestry. Workers in this sector are paid approximately $25,000 per year on average, well below the average statewide wage of $46,000 for all sectors. US Bureau of Labor Statistics. Occupational Employment Statistics: May 2018 State Occupational Employment and Wage Estimates, Florida. https://www.bls.gov/oes/current/oes_fl.htm#00-0000 (2019).

The relatively small role of agriculture in Florida’s economy suggests that any impacts are unlikely to have major economic consequences for the state as a whole. However, individual farmers, farmworkers, communities supported by farming, and others may face more acute effects.

Key Findings

• Quantitative estimates of the impacts of climate change on Florida’s agriculture sector are limited: they cover fewer than half of the state’s counties and only include cotton, soy, and grains (which are small contributors to the state’s agricultural output). Under moderate and high emissions scenarios, “Moderate emissions scenario” refers to RCP 4.5, and “high emissions scenario” refers to RCP 8.5. “Low- and highend estimates” refers to the 5th and 95th percentile estimates from Hsiang et al.5 under both scenarios. median estimates show increased yields of 5–6 percent for cotton and soy, and decreased yields of 1.5–3 percent for grains (including corn). However, substantial uncertainty exists, with lowand high-end estimates of –1 to +12 percent for cotton, –1 to +11 percent for soy, and –8 to +5 percent for grains. Hsiang, S. et al. Estimating economic damage from climate change in the United States. Science 356, 1362 (2017). Yield increases could occur in part due to the benefits of higher CO2 concentrations in the atmosphere.
• Climate change will affect the risks of citrus greening, which threatens Florida’s valuable citrus crops. Citrus greening transmission can occur between 61°F and 91°F, with optimal disease transmission at 77°F. Taylor, R. A. et al. Predicting the fundamental thermal niche of crop pests and diseases in a changing world: A case study on citrus greening. Journal of Applied Ecology 56, 2057–2068 (2019). Climate change will increase the risks of disease transmission during the winter, as average temperatures are projected to rise from 59°F to above 60°F by 2035 under a moderate emissions scenario. However, an increase in the number of summer days with temperatures exceeding 91°F will reduce transmission risk during the summer (average summer lows currently exceed 61°F across most of the state). US Climate Data. Climate Florida - Tallahassee. https://www.usclimatedata.com/ climate/florida/united-states/3179 (2019).
• Cattle, other livestock, and dairy sales generated 24 percent of Florida’s farm cash receipts in 2017. US Bureau of Economic Anlaysis. Regional Data: GDP and Personal Income. https://apps.bea.gov/iTable/index_regional.cfm (2019). But as the climate changes, higher temperatures are likely to increase heat stress on livestock, reducing productivity. Climate change is also projected to reduce breeding productivity in livestock. Gowda, P. et al. Agriculture and Rural Communities. in Impacts, Risks, and Adaptation in the United States: Fourth National Climate Assessment, Volume II (eds. Reidmiller, D. R. et al.) 391–437 (2018).

• Outdoor farmworkers in Florida face challenging working conditions due to exposure to high levels of heat, humidity, and disease vectors (e.g., mosquitoes or other animals that can transmit diseases). Hsiang, S. et al. Estimating economic damage from climate change in the United States. Science 356, 1362 (2017). Under a moderate emissions scenario, labor productivity for such outdoor workers is projected to decrease by approximately 17 percent per worker, but there is substantial uncertainty surrounding this estimate. A high-end (more damaging) estimate projects a productivity decrease of 64 percent, while a low-end (less damaging) estimate projects an increase in productivity of 11 percent. Hsiang, S. et al. Estimating economic damage from climate change in the United States. Science 356, 1362 (2017). Labor productivity increases are possible because of reduced exposure to cold temperatures.
• Climate change is projected to increase the frequency and severity of droughts in the southeastern United States, including Florida. It is also projected to increase the severity of extreme rainfall events. Climate models project drier summers and wetter falls in the southeastern United States, including in parts of Florida. These changing trends may create new challenges for Florida’s farmers.
• Increased frequency and severity of drought will likely exacerbate competition for Florida’s water resources. In 2015, the state’s farms consumed 3.2 billion gallons of fresh water per day—and this figure is projected to rise by 17 percent through 2035. Her, Y. G. et al. Climate Change Impacts and Adaptation in Florida’s Agriculture. Florida’s Climate: Changes, Variations, & Impacts (2017). In 2017, roughly 75 percent of Florida’s planted cropland was irrigated mechanically (i.e., not rain-fed). As droughts intensify, crop irrigation may become more costly.
• Saltwater intrusion is projected to increasingly affect freshwater aquifers in Florida, damaging crops for farmers relying on irrigation from groundwater near the coasts. Tully, K., Epanchin-Niell, R. & Strong, A. The Invisible Flood: The Chemistry, Ecology, and Social Implications of Coastal Saltwater Intrusion. BioScience 69, 368–378 (2019). However, quantitative estimates for these damages are not currently available.
• Climate change is projected to increase the severity of tropical storms making landfall in Florida, leading to higher windspeeds, storm surges, and volumes of precipitation during these events. Kossin, J. P. et al. Extreme Storms. in Climate Science Special Report: Fourth National Climate Assessment, Volume I (eds. Wuebbles, D. J. et al.) 257–276 (U.S. Global Change Research Program, 2017). These more severe storms are likely to increase disruptions to the agricultural sector

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