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Peace Corps Info. Session Peace Corps service is the opportunity of a lifetime. Volunteers have the opportunity to serve in the areas of education, health, environment, agriculture, and business. Please join us for one of our upcoming info session: Info Session Wednesday, February 24, 5-6pm University of Washington ? HUB Room 106B Come listen to a returned Peace Corps volunteer from Uganda who will share her personal experience, answer your questions, and provide tips to guide you through the application process . Questions? Contact the UW On-Campus Peace Corps Rep: Erin Larsen-Cooper Office 134 Mary Gates Hall Hours Mondays 9:30am to 1:30 p.m. ? Fridays 1:00 p.m. to 5:00 p.m. E-mail pcorps@u.washington.edu Phone 206.543.0535 1 Oceanography 102, Nuwer/Strickland Lecture 19 © 2010 University of Washington 2 Effects of Ocean Acidification ? Error on slide (see red text) ? Impacts on organisms that build shells and plates out of calcium carbonate (CaCO3) ? Use bicarbonate (HCO3-) ? More acidic (lower pH) = less bicarbonate ? Vulnerable organisms: ? Coccolithophorids (phytoplankton) ? Pteropods, foraminifera (zooplankton) ? Coral reefs Coccolithophore Corals Pteropod Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington Decreasing CO2 emissions may not be enough 3 Powell (2007) Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington There?s $$$$ in Carbon ? Kyoto Protocol ? Carbontrading Markets ? Credit for financing projects to reduce carbon emissions 4What is the Global Carbon Cycle? 5 Image:www.lbl.gov ? Blue boxes with yellow print = carbon reservoir ? Fixed amount of carbon on Earth ? Carbon ?cycles? among reservoirs ? Can we remove CO2 from the atmosphere and store it in another reservoir? Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington 6 CO2 , Oceans & the Carbon Cycle ? CO2 enters ocean from atmosphere ? Some is stored as biomass (tissues of marine organisms) ? Sinking to depths & to sediments prevents greenhouse contribution Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington 7 Removing CO2 from the atmosphere ? Geoengineering: ?options that would involve large-scale engineering of our environment in order to combat or counteract the effects of changes in atmospheric chemistry." ? Carbon sequestration ? Ocean Storage ? ?Dissolution injects? ? Inject CO2 by ship or pipeline to deep ocean (below 1000m) ? ?Lake Deposits? ? Deposit CO2 directly into sea floor at depth ? At depths greater than 3000m, CO2 is denser than water ? Sinking of crop residues Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington 8 Removing CO2 from the atmosphere ? Geoengineering ? Manipulation of Ocean primary production ? Stimulating phytoplankton growth ? Photosynthesis = carbon fixation (carbon capture) ? Dead phytoplankton (carbon) sink to deep ocean CO2 + H2O + ! C6H1206 + H20 + O2 PhotosynthesisPhotosynthesis as carbon capture ? Phytoplankton ? Drifters ? Single-celled primary producers (make own food) ? Major source of food (carbon) and oxygen in the ocean ? Removes about half CO2 emissions ? Same basic needs as land plants ? N & P nutrients ? micronutrients (Fe) ? Different types of phytoplankton Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington Types of Phytoplankton ? Four main groups: ? Coccolithophores ? range of sizes ? plates made of CaCO3 ? Diatoms ? range of sizes & shapes ? shells made of silica (Si) ? Dinoflagellates ? range of sizes & shapes ? flagella = mobility ? Cyanobacteria ? very small 10 Coccolithophores Diatoms Dinoflagellates Cyanobacteria Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington ?Sequestering? of captured carbon to the deep ? CO2 is fixed by phytoplankton in the surface ocean ? Carbon converted to tissue ? Fixed carbon can be transferred to the deep ocean by: ? Passive sinking of particles ? Physical mixing ? Active transport by zooplankton (vertical migrations & fecal material) 11 Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington 12 The biological pump is the sum of a suite of biologically-mediated processes that transport carbon from the surface to the deep oceanOceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington 13 Some of the carbon is respired and returned the atmosphere Some of the carbon is sinks Some of the carbon stays in surface waters Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington 14 Carbon Sequestration to Deep Water ? Remove carbon from surface waters to depths ? Out of contact with atmosphere for 100?s of years ? Large cells sink faster than small cells ? Cells clump into "marine snow" particles ? Zooplankton fecal pellets ? Sink 10?s-100?s of meters/day vs. 0.1 - 1 m/day for phytoplankton cells Fecal pellets Marine Snow Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington Can we get the ocean to absorb more CO2? ? Can we increase the productivity of phytoplankton? ? Increase nutrient supply ? Pump nutrient-rich water up from depth ? Fertilize the oceans with nutrients ? Macronutrients ? Micronutrients (Fe) ? ?Hungry Ocean? ? http://www.youtube.com/watch?v=VNpLFAbl0F4 ? Others: ? http://www.youtube.com/watch?v=nbSf9tkHUjg ? http://www.youtube.com/watch?v=QzaXtaI2TGQ 15 Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington Distribution of Global Ocean Chlorophyll 16 ? Chlorophyll is a pigment found in phytoplankton ? Indicator of phytoplankton biomassDistribution of Global Ocean Nitrate ? Nitrate (NO3 -) usually main limiting macro-nutrient ? Areas of high nutrients ? Vast areas of low nutrients Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington Why aren?t regions more productive? 18 Chl Nitrate ? Low biomass areas ? Why isn?t production greater in areas where nutrients are high? Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington 19 High Nutrient, Low Chlorophyll Areas ? Large areas of the oceans where there are excess macro-nutrients but no growth ? ?High Nutrients, Low Chlorophyll? (HNLC) ? Antarctica, equatorial Pacific, Gulf of Alaska ? Phytoplankton are not using available macronutrients ? Why? ? Low temperature, insufficient light, overgrazing? ? Something else is limiting growth?? Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington 20 The Iron Hypothesis: John Martin ? Chemical Oceanographer ? Trace Metals ? Suggested micronutrient was limiting phytoplankton production ? Found metals were plentiful, if wildly variable in sea water ? Decided to check for contamination John Martin RustIron (Fe) in Sea Water ? Toughest metal to measure free of contamination ? 5% of dirt ? Used ultra-clean techniques ? All washed plastic equipment in acid ? Positive pressure?air blowing out of lab to keep dust from coming in ? Kevlar instead of steel cable ? Bottle closed passing through surface. ? Nothing touches the decks ? Iron at a few parts/trillion in the open N. Pacific ? Did not attract immediate attention Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington 22 What is the role of Iron in HNLC regions? ? Martin argued iron deficiency for photosynthesis could account for HNLC ? Iron is an essential micronutrient ? Martin proposed dumping 30K tons of iron into the Southern Ocean to combat global warming ? "1/2 Tanker of Iron = Ice Age" ? (Intended as a wise-crack) Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington 23 The Iron Hypothesis ? Why Iron? ? Essential micronutrient required for photosynthesis (electron carrier and catalyst) ? 1987?1990 measured iron in the 3 HNLC areas ? Found low iron in all 3 areas According to Martin's iron hypothesis, seeding the ocean surface with iron should make phytoplankton multiply dramatically, which would draw CO2 from atmosphere to the oceans and might in turn cool the planet. Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington ? Vostok ice core data (Antarctica) ? Link low CO2 with low temp and high levels of iron-rich dust 24 The Iron-Climate Connection Powell 2008Why are HNLC regions low in Iron? ? At least half (95%?!) of iron in surface ocean comes from atmosphere ? Very low iron abundance in deep water because of insolubility ? Areas downwind of dry continents would get lots of iron ? E.g., equatorial Atlantic downwind of Sahara Aeolian sources of Iron Oceanography 102, Nuwer/Strickland Lecture 20 © 2010 University of Washington 26 Why are HNLC regions low in Iron? ? Areas far from land get little iron ? Antarctica is ice-covered so does not shed iron to atmosphere ? Equatorial & North Pacific far from land ? Red = high dust content in atmosphere www.atmosphere.mpg.de/enid/og.html