Transcript Climate Change

Climate Change and Coastal
Wetlands
Presented by:
Sidrotun Naim
Susanna Pearlstein
Valerie Herman
Matt Carter
Global Natural Disaster
US Coastal and Marine Facts
 95,000 miles of coastlines
 3.4 million square miles of ocean
 53% of US population live on the 17% of land in the
coastal zones
 Global sea level rise: 4-8 inches in century
 Estimation: additional 19 inches by 2100
How coastal and marine
environments are linked to our
climate
Shoreline erosion and Human
communities
Threats to Estuarine Health
 Estuaries are extremely productive ecosystems
 Increased run-off would deliver increased amounts of
nutrients such as nitrogen and phosphorus
 Decreased run-off would reduce flushing, decrease the
size of nursery zones, allowing predators to penetrate
Coastal Wetland Survival
Coral Reef Die Offs
Stresses on Marine Fisheries
Annual Shoreline Change
Wetlands
Chapter 11
 Methane, CH4, emitters
 20-25% global emissions
 50% of world wetlands LOST, methane emissions are
increasing, anthropomorphic causes
 21 times more effective greenhouse gas than CO2
 Carbon sequestration
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20-30% stored in wetlands
Peat deposits
Permafrost
Restored & created wetlands
Mid Atlantic Coastal (MAC)
Region
 Poor water quality
 Coastal Squeeze
Heavily Populated!
http://www.epa.gov/climatechange/effects/coastal/index.html
Delaware Bay
1.6% of DE lost
21% of marsh land
flooded
But
<1% of affected area
Is developed
Chesapeake Bay
Salt water marshes today lack
Sediment
Oxygen
Organic matter
accumulation
Due to:
Poor water quality
Dams
Farmland abandonment
Now add climate change….
 Most hypoxic estuary in MAC
 Fresh water marshes have high river sediment influxes
 Steep topography, sea level rise will increase erosion
Management & Warnings
 Wetlands will be protected if they fall under socially
significant areas
 Repeating the inland floodplain experience
 Federal subsides for dynamic & hazardous zones
 Structures to control hazards & sea level rise
 Increasing vulnerability
Chemical and Biological Changes
 Extreme weather events and rising sea level alters:
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Salinity
Ionic Exchanges
pH
Microbial Communities
Organic and Inorganic Content
Nutrient Exchanges
 Earlier litterfall
 3 - 5 times as much N, Mg, P, K
 Transported during runoff /flooding
 Nutrient uptake is hindered by:
 Uprooting
 Swaying
 Water logging
Damages to Plants/Animals
 “Woody vegetation” is damaged more than “herbaceous
vegetation”
 Breakage increases infestation
 Microbial community differs in aerobic and anaerobic conditions
 Water quality directly affects food chain
 Hypoxia
Image from www.montgomerybotanical.org
 Osmotic stress
 Turbidity
 Seed distribution
 Biodiversity
Mitigation
 Allow sediment to distribute naturally
 Plan communities that allow coastal wetland migration
 Project future outcomes using models:
 Space-For-Time Substitution paired with long-term
monitoring
Image from soundbook.soundkeeper.org
Hurricanes lose their force dramatically as the system moves toward land,
therefore wetlands around coast regions provide delicate buffer zones to slow the
storm system down before it reaches more populated regions. The levees in New
Orleans are causing dramatic wetland loss.
The levees built to prevent flooding in the cities also
prevent recharge of coast wetlands of the Mississippi River
Delta. The Delta is cut off from its life force and is being
destroyed at a rate of 24 sq. miles a year. Over 1900 sq. miles
have disappeared since the 1930s. As the wetlands decrease,
the city becomes more and more vulnerable to hurricane
without the precious buffer zone.
 Fixing the problem is costly and time consuming. Old
Christmas trees are strategically place around the delta to
collect sediment, and 14 billion dollars is being used for
manual sediment recharge and diversion of the Mississippi
around the levees to recharge other areas of the delta.
 Hurricanes are actually vital for wetland survival in that
the storm surge washes and spreads all of the
sediment, silt, and nutrients the wetlands of the delta
could ever need. A hurricane of smaller proportions
could easily do the work of all of the wetland projects.