Ocean Uses and Human Impacts Outline

Ocean Uses and Human Impacts

Outline • • • Marine Resources Mariculture Drugs Marine pollution Invasive species Climate Change

Classes of Marine Resources Physical resources Mineral deposits, petroleum, natural gas, freshwater Biological resources Plants and animals, microbes Marine energy resources Energy from heat or motion of water Non-extractive resources Transportation, recreation, waste disposal

Petroleum and Natural Gas Oil and gas are often found together beneath impermeable caprock. Drilling for oil offshore requires specialized equipment and is more costly than drilling on land.

Gulf of Mexico Oil Spill 5000 barrels/day 15000 barrels/day Containment (booms), skimming, dispersants, Domes, caps, siphons, new well Full recovery will take many years

Salts and Minerals • • • Magnesium Sodium chloride Manganese nodules Phosphorite Metallic sulfides and muds

Fresh Water • Only 0. 071% of Earth’s water is liquid, fresh, and available at the surface for humans • More than 1500 desalination plants worldwide • 3. 5 billion gallons/day, and rising!

Marine Energy – Wave Motion Energy generated by waves (Dr Brekken) and tides

Biological Resources Major types of commercially harvested fishes, crustaceans, and mollusks

Biological Resources World Commercial Catch of Marine Fishes, Crustaceans, and Mollusks, by Species Group, 1997 Millions of Metric Tons Species Group Herring, sardines, anchovies 21. 5 Jacks, mullets, sauries 10. 9 Mollusks 15. 5 Cods, hakes, haddocks 10. 2 Redfish, basses, conger eels 7. 4 Crustaceans 6. 8 Tunas, bonitos, billfishes 4. 8 Mackerel, snooks, cutlass fishes 5. 2 Flounders, halibuts, soles 1. 0 Miscellaneous Marine Fishes 17. 5 Total for all sources 100. 8 Table from Garrison, 4 ed

Fisheries Typical evolution of ocean fisheries

Fisheries Exploitation

Concept of a Stock A population of a species of fish that is reproductively isolated in space and time Each stock must be treated separately in assessing fishing impacts

Stock Equilibrium Growth Recruitment Stock Size (Exploitable Biomass) Mortality Fishing Removals These four factors must remain in balance for stock equilibrium to be achieved

Maximum Sustainable Yield

CPUE Catch Per Unit Effort

Community Effects ® Altered trophic webs Keystone species may be removed or reduced ® Fishing down food webs The mean trophic level of a marine ecosystem is reduced

So, what can YOU do? w Support sustainable fisheries with your $$ w See: MBARI Seafood Watch wallet card w http: //www. mbayaq. org/cr/seafoodwatch. asp w See also: w http: //www. seafoodinfocenter. org/search. html w http: //www. seafoodchoices. net/

Potential Harmful Impacts of Mariculture w Escape of nonnative species w Herbicides w Disease tolerance and spread w Nutrient enrichment -> eutrophication

Drugs • Researchers estimate that 10% of marine species may contain useful medical compounds • Acyclovir, the first antiviral compound approved for humans, is derived from a Caribbean Sea sponge • Pseudopterosins, a class of antiinflammatory drugs, is derived from marine species • Bone substitute for speeding regrowth of bone grafts is available from Corals. Coral skeletal structure is remarkably similar to human bone

Marine Pollution - DDT w Levels of organic pollutants may be low, but biological amplification concentrates harmful toxins w The concentration of DDT in the fatty tissues of organisms was amplified up to 10 million times in a food chain off the coast of New Jersey

Marine Pollution – HABs and Anoxia

Invasive Species w Introduced species crowd out native species, alter habitats, and impose economic burdens on coastal communities. w The rate of marine introductions has risen exponentially over the past 200 years and shows no sign of leveling off. w More than 175 species of introduced marine invertebrates, fish, algae, and higher plants live in San Francisco Bay. w http: //www. invasivespecies. gov/

Invasive Species – Zebra Mussel

Recent US Bioinvasions http: //www. pewoceans. org/reports/introduced_species. pdf

Global Warming

Arctic Ocean and Sea Ice

Mountain Glacier Retreat 1858 2001

“The Snows of Kilimanjaro”? ?

Antarctic Ice Sheet

Antarctic Ice Sheet EAIS WAIS

Both Greenland Ice Sheet and West Antarctic Ice Sheet = 6 m global sea level. 25% of U. S. population lives within 10 m of sea level. WAIS

People at risk w Country population Bangladesh 115 million Egypt 55 million Indonesia 185 million Maldives 0. 2 million Pakistan 110 million annual income $160 $710 $450 $300 $350

The Prez

4 Overarching Conclusions: Climate Change is coming at us a lot faster than we thought. We are not going to get through this crisis without casualties – if at all All the stuff about changing light bulbs and driving hydrids is practically irrelevant to wholesale de-carbonization by 2050. Over-Population and “carrying capacity” of Earth. We need C-free energy and C-sequestration It is not realistic to reach the 2050 goal because we have started too late, so we need geo-engineering solutions to buy time The political environment becomes increasingly more unstable with increasing Temperature; this will be the next military challenge after the Middle East

Solutions are Clear and Reachable No fine-tuning yet, but we know how to keep <2°C, and so prevent going beyond 450 -500 ppm CO 2 world We are acting to preserve one particular climate state among many potential ones within the “deep glacial” to “greenhouse extinction” spectrum We have only fragmentary knowledge of how the climate system works so we must learn much more about it

Strategy for the Short Term Keep the T’s under control to prevent “runaway” greenhouse Avoid loss of prime agricultural land, major population dislocations, spread of disease/famine, slowdown of thermohaline circulation Maintain high-energy technology/industry but move to completely de-carbonize, replace decimated forests, create large MPAs Reduce population, produce more protein, less sugar

“Final Exam” Metaphor Fossil fuels have provided the means to develop the western world’s high standard of living: longer lives, security and leisure, democratic political states, universal education, community welfare, high levels of equality, and international institutions for peace and prosperity. However, this is a “one time deal” for building the present industrial state!! We now have to manage, in your lifetimes, the transition to a new technology-based industrial state: mostly in the next 20 years completely de-carbonize by 2050 hold the line on 2°C increase, and return to 350 ppm

“Final Exam” Metaphor We barely survived the mid-term exam (cold war and nuclear annihilation) Knowledge, self restraint, resolve and cooperation are required We have some chance of “passing”, and how interesting the long future that stretches ahead will be, if we do pass!

Challenge for Your Generation w 1870 -1900 US Railroad system built w 1940 -1970 Interstate highway system w 1960 -1970 Apollo mission to the Moon w 1950 -1990 Cold War, nuclear threat w 1960 -1980 Green revolution, agriculture w 1990 -2010 Internet; Global change

Everybody Likes a Challenge w 1990 -2010 Recognizing climate change w 2010 -? ? Mitigation and Adaptation