Climate change, fisheries, and disturbance in the Gulf of Mexico

[mbjones]

Author: Alexander Sacco Topics: ocean warming, climate change, fisheries, disturbance events

Summary of Synthesis

Ocean warming accounts for over 90% of the energy accumulation for the past 40 years, with surficial warming over 0.1 deg. C per decade (IPCC 2014). In addition, sea level has risen from ice sheet melting, freshwater runoff, and increased freshening of precipitation-high areas, while evaporation increasing for high-salinity oceanic regions is predicted to increase (IPCC 2014), which is a concern for coastal areas, including the western coast of Florida. With increasing ocean temperatures, this could mean changes in marine species distribution which can not only affect management of species, but also commercial fisheries and subsistence fishing success and shift towards areas that are more productive. Spatial distribution and species composition of fish and other commercial species would also potentially shift their range. Fishing success is crucial for coastal areas as a source of income for fishermen, as well as tourism and food and service industries of these areas. Sea level rise, which is project to eventually submerge low-elevation parts of Florida, Louisiana, and the Gulf-region states, would lead to decreased livable area for major cities including Miami, New Orleans, and Tampa (Gregory et al. 2013). Lastly, extreme weather events are regularities in the Gulf of Mexico, and the effect of these storms on the livelihood of costal inhabitants, public perception of safety, and tourism will also be studied, as well as establishing a baseline for hurricanes, tropical storms, flooding, tornadoes, and other weather events in the region that may have economic impacts on coastal areas. The important temporal periods will be defined as: (a) before Hurricane Katrina [2000 – 2005], (b) after Hurricane Katrina but before the Deepwater Horizon oil spill [2005 – 2010], and (c) after the Deepwater Horizon oil spill [2010 – 2015]. Thus, we will focus on these five topics for the Gulf of Mexico: (1) rising ocean temperatures and their effects on species distribution and species composition changes; (2) fishing success for commercial and subsistence fishing effort; (3) economic impacts of past weather and environmental disasters (e.g.: Hurricane Katrina, Deepwater Horizon oil spill) for coastal areas along the US coast of the Gulf of Mexico; (4) Extreme weather events and their impact on coastal economies.

Data needs

Data needs for the synthesis project will include, for goal (1): collection of marine species distribution and abundance data in the Gulf of Mexico, environmental data of the ocean and atmosphere from the satellite record and interpolated in-situ measurements, and habitat selection data for species, if available. For goal (2): fisheries effort by fishing entity and a model of subsistence fishing based on interviews with subsistence fishers. This will require interviews be conducted across multiple states and economic levels from the three temporal periods defined above. For goal (3): examination of revenue for private companies and local and state governments in coastal regions. Lastly, for goal (4): using climate and weather models, economic disaster amounts, and past observations of extreme weather events will be used to determine the impact on coastal communities in the Gulf of Mexico.

Analytical approaches

Analytical approaches will include surveys and in-person interviews for inhabitants and tourists/potential tourists of the Gulf States coastal areas for each of the three time periods. This will include economic data for 2000 – 2015 in order to assess economic gains or loss from these extreme weather events. Marine data will be analyzed through models, image analysis and remote sensing Level 1 – Level 3 data, and GIS methodologies in order to assess and project species abundance, distribution, and composition in the Gulf of Mexico, as well as their likelihood of shifting distributions due to oceanic warming and sea level rise. Lastly, we will use fishing effort data and financial information from fishing entities in order to assess and predict effects of extreme weather and environmental disasters to Gulf-based fisheries and subsistence fishing efforts. Subsistence fishing efforts will be collected via surveys.

Impacts

This synthesis will have far-reaching impacts in climate scientists, social scientists, tourism boards, and Gulf of Mexico stakeholders – including energy exploration, tourism-based corporations (travel agents, lodging, restaurant, and retail businesses, etc.), coastal inhabitants and their families, tourists to the coastal regions of the Gulf States, and federal and state management and policy makers for marine conservation and fisheries. This will enable us to accurately describe, both scientifically, economically, and personally, the impacts of extreme weather and environmental disasters. This study could be a case study for more coastal impact research studies in other areas of the world that lie in the subtropical and tropical regions.

[adellapa]

Overall, I think this project has good potential, though it needs to have smaller and more feasible objectives. I am confused about the link between the five topics. I would suggest to streamline the focus of the project to enhance viability and how results can be used by the scientific and management's community across the Gulf. For example, I don't see that much link between changes in marine species distribution/composition and economic impacts of events like Katrina and Deepwater Horizon oil disaster, although I can see how some datasets on environmental data may be used for both topics. Personally, I would be more interested in analyzing or modeling the potential impacts of climate change on species distribution, perhaps by focusing on one species as an example (e.g., tunas, oyster, or others). I think this information might be more helpful considering the ongoing restoration effort for the oil spill, for which monitoring plans lacks knowledge on the forecasted impacts of climate variability. Also, for data needs I would suggest to include also other important data, if available, such as Chlorophyll-a (proxy for primary productivity), dissolved oxygen, and pH. For the interviews and surveys, do you already have the data for the analysis, or where are you planning to get those?

[aesacco]

Thank you @adellapa, I agree that it does encompass a few too many objectives. I had envisioned a full Gulf-focused study, but in retrospect, there should be at least two projects here. Your idea for climate change impacts on species distributions sounds like a feasible project to complete in the time we have at NCEAS next month. The interview and surveys have not been conducted by myself, but I was hoping to conduct them based partially on BOEM's Offshore Oil and Deepwater Horizon: Social Effects on Gulf Coast Communities series. This, however, would be a bit off the path of the main idea.

[berisman]

As part of our work on fish spawning aggregations in the Gulf of Mexico (and Caribbean), we've been looking at the impacts of climate change on the phenology (timing) and spatial distribution of spawning aggregations. We're just finishing up our first case study using an iconic species (Nassau Grouper) but are now expanding to look at other species. We're finding that the predicted effects of climate change on species distributions change rather substantially depending on what life history stage you investigate (e.g. non-spawning adults vs. spawning aggregations). I could see some clear opportunities to merge ideas here.

[aesacco]

@berisman I definitely agree on distribution variations based on the life stage that is being investigated. We see something similar in some pinnipeds, and it would be interesting to see how this plays out through some Gulf-based species. I'm interested in looking into combining some of our ideas!