Intersection of Policy & Trends: Climate, Hypoxia, and Louisiana s Coast

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1 Intersection of Policy & Trends: Climate, Hypoxia, and Louisiana s Coast Doug Daigle Louisiana Hypoxia Working Group Louisiana Water Conference March 27, 2018 Louisiana State University

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5 Mississippi River Gulf of Mexico Ecosystem Continuum Mississippi River Atchafalaya River New Orleans Hypoxic Area * Effects are more far reaching than suspended sediment plume, esp. N & somewhat P Source: N. Rabalais, LUMCON dominant wind direction

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8 2017 Gulf Hypoxic Zone 22,720 square kilometers 8,776 square miles LUMCON/LSU Mapping Cruise July 24-30, 2017

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10 Brown Shrimp The Consequences Fisheries resources at risk Altered migration Reduced habitat Changes in food resources Susceptibility of early life stages Growth & reproduction

11 Nutrient Yields from the Mississippi Basin Alexander et al. 2008

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15 We strive to reduce the five-year running average areal extent of the Gulf of Mexico hypoxic zone to less than 5,000 square kilometers by the year Reaching this final goal will require a significant commitment of resources to greatly accelerate implementation of actions to reduce nutrient loading from all major sources of nitrogen and phosphorus in the Mississippi/Atchafalaya River Basin (MARB). An Interim Target of a 20% reduction of nitrogen and phosphorus loading by 2025 is a milestone for immediate planning and implementation actions, while continuing to develop future action strategies to achieve the final goal through Federal agencies, States, Tribes and other partners will work collaboratively to plan and implement specific, practical and cost-effective actions to achieve both the Interim Target and the updated Coastal Goal.

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20 MRBI Watershed Selection State Technical Committee input Information to consider: CEAP data/results SPARROW data State-level water quality data Nitrogen/Phosphorus monitoring/modeling State-level nutrient strategies/priorities Focus Area

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23 A number of Innovative Watershed Projects have been evolving to address these issues in the Mississippi River Basin Cannon River Watershed Partnership Cedar River Watershed Project Iowa Soybean Association Watershed Progam Blue Earth River Basin Root River Watershed Chippewa River Watershed Project/ Chippewa 10% Project The Madelia Model

24 A number of recent papers examine impacts of climate change on hypoxic zones Breitburg et al (2018): Rising nutrient loads, coupled with climate change (both from human activities) are changing ocean biogeochemistry and increasing oxygen consumption Oxygen concentrations in both open ocean and coastal waters declining since at least mid-20 th century Increasing stratification and weakening overturning circulation

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26 Climate impacts on hypoxic zones and shelf, cont. Altieri et al (2014): found majority of documented dead zones occurred in regions predicted to experience over 2 degrees Celsius warming by end of this century Range of effects includes ocean acidification, as increased carbon lowers ph of seawater and affects carbonate chemistry Turner, Rabalais, Justic (2017): dataset from Louisiana s shelf - summer bottom-water warming 1.9 times faster than local summer air temperatures, 6.4 times faster than concurrent increase in annual global ocean sea surface temperatures

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31 An area of opportunity: floodplain reconnection and restoration Collateral benefits: habitat, nutrient uptake, carbon burial, flood control Reconnecting floodplain can take pressure off levee system and reduce maintenance/repair costs from high water events Upstream action benefits coastal restoration by reducing nutrient loads Hanberry et al (2014) - LMAV

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34 An area of opportunity: floodplain reconnection and restoration Floodplain reconnection and restoration can occur fairly quickly Floodplain and coastal restoration have to be coupled with reduced inputs of both N and C from sources for optimum results Current question of national climate policy - previously aimed at reducing emissions, now reversed

35 An area of opportunity: floodplain reconnection and restoration Floodplain reconnection and restoration can occur fairly quickly - TIMING Floodplain and coastal restoration have to be coupled with reduced inputs of both N and C from sources for optimum results SYSTEM Approach Current question of national climate policy - previously aimed at reducing emissions, now reversed Sea-level? DIRECTIONAL Factor

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