Lecture 25: Anthropogenic Changes: Oceans pick up HW 7, 10 older HW outside *** check your grades online! *** HW9/aqu trip 1 will be destroyed today 2 office hours: tomorrow, next MONDAY 2 discussion sessions this week (none next week) Humpback Whale early final exam (tue or wed; noon) email glaske@ucsd.edu for details Lecture 25-2018: Anthropogenic Changes: Water and Oceans Friday 12/1/18 M=7.0 Alaska earthquake this was NOT the big one! Not even close! Not even for this year! (Mw=7.9 Jan 2018) M=7.0 Anchorage normal EQ mechanism AK has largest EQs in U.S., and plenty Lecture 25-2018: Anthropogenic Changes: Water and Oceans Title goes here 1
Alaska oil pipeline � above-ground/on stilts � sliders to accommodate EQ motion � survived 2002 M=7.9 Denali EQ Lecture 25-2018: Anthropogenic Changes: Water and Oceans PQ13: for a total credit of 0.6 pts (0.15 pts attendance credit) Use our form only! in class < 25 min – no PQ! we check ID! we allow 10.5 PQ credits Lecture 25-2018: Anthropogenic Changes: Water and Oceans Title goes here 2
The Earth’s Oceans sea level rise! • 70.8% of Earth’s surface • hold 95% of Earth’s water • oil fields/resources • take up heat • take up CO 2 • food source (200 Mio people depend on fishing) • 60% of population live along coasts Lecture 25-2018: Anthropogenic Changes: Water and Oceans The Warming Oceans � sea level rise (1 m by 2100) -> costal erosion; loss of habitable space � warm freshwater on top -> stable layering -> no upwelling -> no food (e.g. Peru during El Nino as example of things to come) � weakening of cold currents -> no upwelling -> hurricanes advance (i.e. landfall of hurricanes in San Diego possible) � coral bleaching if T rises 1-2ºC corals face multiple threats -> 2003: 25% gone compared to 1980s coral reefs: “the rain forest of the ocean” (high biodiversity!) Lecture 25-2018: Anthropogenic Changes: Water and Oceans Title goes here 3
California’s Kelp Forest giant brown algae Garibaldi (kingdom protista) Cali state fish • grows up to 30cm/day to 60m • needs water < 20ºC (68ºF) • important habitat • resource (iodine, alkali) • used for things from soap to glass • alginate thickens ice cream, jelly, toothpaste Lecture 25-2018: Anthropogenic Changes: Water and Oceans Ocean Acidification 0.138”=3.5 mm • cannot produce protecting carbonate shell -> dies ?? interruption of base of food chain • ocean chemistry changes 100 times faster - > mass extinction?? than in last 650,000 yrs • acidity increased by 30% in 150 years (pH from 8.16 to 8.05) check grade for HW7 2a) • projected decrease to pH 7.85 by 2100 (150%) Lecture 25-2018: Anthropogenic Changes: Water and Oceans Title goes here 4
‘Hawaiian’ Humpback whales – 12/2/18 • baleen whale • food: krill, small fish • Arctic in summer (to feed) • Hawaii during winter (to fast, calve) • cause for decline: too early to tell • lack of food in Arctic? • annoyed by humans -> relocated? Lecture 25-2018: Anthropogenic Changes: Water and Oceans � sewage � waste disposal � unregulated disposal from cruise ships World: 200 large cruise ships Amount of waste of each/day: � 95,000 l raw sewage from toilets � 540,000 l sewage from sinks, galleys and showers � dredging � 6 tons of garbage and solid waste � 56 l of toxic chemicals � draining � 26,500 l oily waste water � development Lecture 25-2018: Anthropogenic Changes: Water and Oceans Title goes here 5
Plastic, the Wonder Resource … or is it? • made from petroleum • plastic not bio-degradable • plastic difficult to recycle • only small fraction is recycled (3.5%) • it takes sunlight a long time to break down plastic • plastic now finds its way to remotes oceans • ocean fish and birds mistake plastic for food a plastic bottle takes 450 years to degrade Lecture 25-2018: Anthropogenic Changes: Water and Oceans The Great Pacific Garbage Patch – Pacific Vortex • discovered in 1997 by Cpt. Charles Moore (Algalita) • North Pacific Ocean Gyre • at least 2x Texas • “so bad it may be is economical to remove” • plastic bottles take 450 years to disintegrate Lecture 25-2018: Anthropogenic Changes: Water and Oceans Title goes here 6
Over 200,000 Laysan Albatross Chicks/year Die Loaded w/ plastic SD Tribune 11/29/08: “…98% of Albatross chicks have plastic in their stomach…” Lecture 25-2018: Anthropogenic Changes: Water and Oceans 1972: The Club of Rome: The “Limits of Growth” Lecture 25-2018: Anthropogenic Changes: Water and Oceans Title goes here 7
Source: FAO/Wikipedia The “Healthy” Ocean: The Consequences: 1950: 20 Mio tons worldwide 1997: 122 Mio tons - 11 of 15 of most important fishing areas fully or overexploited - 70% of major fish species affected - landings of cod, tuna, haddock dropped by 95% since 1970 - many > 90% exploited: tuna, cod, marlin, swordfish, halibut - aquaculture masks effects of overfishing Lecture 25-2018: Anthropogenic Changes: Water and Oceans The Oceans as a Food Source Source: Science News 9/17/16 MSC founded 1997 in London aquaculture (farming in the water) 2005: accounts for about 30% of fish catch, and growing 2016: up to 44% and growing, stress on wild populations - good example: catfish (majority in U.S.) - bad example: salmon (feeds on small wild fish)/spread of pests/diseases - color-coded fish cards help consumers decide; UPDATED EVERY YEAR!! - industry DELIBERATELY mislabeling fish for larger profits Lecture 25-2018: Anthropogenic Changes: Water and Oceans Title goes here 8
Source: Wikipedia; Hans-Petter Fjeld Cod thrives in 0-10ºC -> sensitive to global warming 1498 Cabot: “ codfish ran so thick they were easily caught by dangling a wicker basket over the side of the vessel ” 6-7ft long; 200 pounds who is next? Pacific Salmon??? Lecture 25-2018: Anthropogenic Changes: Water and Oceans Fish cards -Salmons: farmed- red /wild - green Earthwatch Nov 06, 2017 Earthwatch Nov 06, 2017 Lecture 25-2018: Anthropogenic Changes: Water and Oceans Title goes here 9
Source: World Watch Institute purse seine nets - poisoning with sodium cyanide (S.E. Asia) - dynamite (Mediterranean; abandoned?) - gillnets/drift nets (trap/drown large mammals) - trawling (all shelves at least once in 2 years) 150 x area of clearcutting global forest from: “Essential of Oceanography” by Trujillo Trawling Lecture 25-2018: Anthropogenic Changes: Water and Oceans from: http://www.wikipedia.org Source: World Watch Institute * 20 Mio tons (~20%) thrown away as by-catch - fish too small - not marketable - lack of permit - this number does not include killed mammals and birds - use fine nets - 5 kg unwanted species for every 1 kg shrimp Lecture 25-2018: Anthropogenic Changes: Water and Oceans Title goes here 10
- Loggerhead Turtle - up to 450 kg - lifespan up to 67 years - maturity: 17-33 years - Loggerhead and Leatherback migrate across oceans (need international protection!) Lecture 25-2018: Anthropogenic Changes: Water and Oceans Vaquita Totoaba By-Catch - world’s smallest dolphin Illegally fished - Gulf of California - for Chinese meds - less than 30 left - Gulf of California - CRITICALLY ENDANGERED - Mexico banned harvest in 1975 - catch-to-protect FAILED! - CRITICALLY ENDANGERED Lecture 25-2018: Anthropogenic Changes: Water and Oceans Title goes here 11
Sharks Whitetip Shark (OldakQuill, wikipedia) Whale Shark Georgia Aquarium (Zac Wolf, wikipedia) � true fish � whale shark largest fish � has lived on Earth for 450 Mio yrs Lifespan Greenland shark: Thresher Shark (Paul Ester, wikipedia) > 400 years Lecture 25-2018: Anthropogenic Changes: Water and Oceans � sharks fined, then thrown out to die � 1 bowl of soup cost $200 -> booming industry � 100 Mio sharks caught each year -> 8000 tons of fins � now banned in Atlantic and Mediterranean Lecture 25-2018: Anthropogenic Changes: Water and Oceans Title goes here 12
Declining Shark Population in NW Atlantic 65% 89% 80% � come in all sizes (few inches to 15m) � some species declined by 80% and more in just 15 years! Lecture 25-2018: Anthropogenic Changes: Water and Oceans The Oceans as a Food Source Source: World Watch Institute The Consequences of Declining Supply: - out-of-work fishermen (Canada, Europe) - tension over fisheries worldwide (Canada-Spain, 1995) - piracy (South China Sea) SOMALIA!!!!!! - food ????? Somali Pirates Source: wikipedia/U.S. Navy Lecture 25-2018: Anthropogenic Changes: Water and Oceans Title goes here 13
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