• Final Thoughts LAST TIME . . .ended here
– Turn in Long Lab Field Trip (HW-1)
– Please do HW-2 (due July 7th)
– Wed – Final Chemical Oceanography -CO2_The Oceans
& Ocean Physics
Fe2+
Ca2+
NO3-
OUTLINE
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Foundations of Chemical Oceanography
Periodic Table – Valence Electrons
Water – It’s Unique Properties
Dissolved Elements in SeaWater
Sources & Sinks
Carbon Dioxide & the WORLD Ocean
– Intro to Global Warming
• Residence Times of Elements REMOVE?
– When sources/ sinks in balance – ocean is steady state
– At steady state – can define the amt. of time
For total mass of an Element (e.g. Na) to be replaced
– aka Residence Time (how long it is in the ocean)
– Residence Time
• = mass of element present / rate of input or removal
• Na
– 1.472 x 1011 kg yr-1 tons/ year / 2 x108 tons/yr-1 Na/year = 70 million years!
Recall - Periodic Table _Valence Electrons
Outer valence electrons (= e-) participates in bonding of Elements
e.g.
CO2
4 e- = (.)
carbon dioxide
..
..
O::C::O
‘‘
‘’
Covalent bond
Sharing e- 
O=C=O
CO2
6 e- = (.)
• CO2
– Aka, dry ice O=C=O
– More CO2 you add
• the more acidic the water
MORE acidic
• Carbon Dioxide & the WORLD Ocean
– Is human released (= anthropogenic) carbon dioxide (CO2)
• Changing the Earth’s Climate? ?
– CO2 traps heat in earth’s atmosphere as a greenhouse gas
» Other gasses: CH4 (methane), CFCs, H2O
CO2, CH4 (methane),CFCs, H2O
• Who/ where is the real contribution(s)
Per Capita and Total Carbon Dioxide Emissions, 2005
CO2 emissions in tons per person
Total CO2 emissions in million tons
Source: Source: U.S. Energy Information Administration (EIA)
• Two International Research Programs
– Joint Global Ocean Flux Study (1988-1998)
– World Ocean Circulation Experiment (1990-2002)
• To estimate oceanic storage of CO2
– Oceans ~could account for 48% CO2 released thru human activity
– Greatest CO2 in Deep waters: N. Atlantic & intermediate Atlantic, S. Oceans
»`
»
why it this?
to be continued
• Carbon Dioxide & the WORLD Ocean
– Increase in CO2 in Atmosphere Increase CO2 in World Oceans
– Concurrently  seen increase in pH (more acidic) surface waters
• diff of ~ 0.4 pH (not a big deal?)
RecaLL
0.4 diff =
4Xs more acidic!
Acidic means
more H+s donating
vs
Basic
H+ accepting. . .
• Marine Carbonate System and pH
– Little CO2 exists as gas in Seawater,
• Mostly in chemical form: Carbonate Buffering System
• 0.4 pH diff. in Oceans b/c of Carbonate Buffering System
– Favors formation of Carbonate and (H+) (see below)
MORE acidic
calcite
Ca2+CO32-
Shells dissolve shallower  recall lysocline
This lowering of pH
(more acidic) effects
dissolution rates of
phytoplankton shells?>
• Marine Carbonate System and pH
• Anthropogenic (Human produced) Carbon Dioxide
– 2 major sources:
• Burning of fossil fuels
• Deforestation
Challenge Question
How much have atmospheric CO2 levels risen since 1800?
Year Amount
1800 – 270 ppb
2004 – 380 ppb (30% increase)
• Anthropogenic (Human produced) Carbon Dioxide
– 1958, David Keeling (Scripps Institute)
• Mauna Loa Observatory, HI
• CONTINUOUS (daily) CO2 measurements,
– Sawtooth pattern indicates variation due to:
» Warm seasons: plants consume CO2 (drops)
»
Cold seasons: animals, plants release CO2 (rise)
Trend indicates
Increased atmospheric CO2
levels b/c
~ burning of fossil fuels. .
• Anthropogenic (Human produced) Carbon Dioxide
– Fate of anthropogenic CO2 in Atm. is uncertain
• Sources/sinks reveal discrepancy ~ 2 gigatons (Gt)
– i.e. there is less CO2 in atmosphere then should be present
– Based on what know about SOURCES & Sinks
– The MISSING Carbon Problem: addition Puzzle for Climate modeling.
• Estimation of the Sources & Sinks of Carbon to the Atm.
– Req. understanding of ~ The GLOBAL Carbon Cycle
– What is it?
• The exchange of Carbon b/w various carbon reservoirs via
– bio-geo-chemical processes
– Amts. in Gigatons (Gt)
• The GLOBAL Carbon Cycle
– Total Carbon in Earth Reservoirs: Sources
• 1) mainly stored in Sedimentary rocks
– e.g. limestone or dolomite
~82,370,000 Gigatons (Gt)
Ca2+CO32-
CaMg(CO3)2
• 2) as organic carbon buried in sediments
• 3) CO2 dissolved in world Oceans
1
2
3
~15,500,000 Gt
~
36,000 Gt
– More then fossil fuels, the atm. Living organism combined
• The Global Carbon Cycle
– Residence Time also Important
• Scientists interested in process that move Carbon from reservoir to another
• Small Changes in Reservoir  MAY have profound effects
• Large Reservoirs may exert disproportionate influence on small reservoirs
– Organic carbon as Fossil fuels ~residence time: thousand years
LAND
OCEAN
The Global Carbon Cycle - Residence Time also Important
• Temporal scales exist over which Carbon transfer ~ ranges
– e.g. Months  thousands of years
• Thus Scientists Recognize 3 diff Carbon Cycles based on
their time scales: What are they?
– 1. Short term Organic carbon cycle
» Atm & biosphere (seasonal - Keeling Curve 1958-)
– 2. Long-term Organic carbon cycle
» Formation of fossil fuels (burial of organic carbon (dinosaurs, plants))
– 3. Long-term InOrganic carbon cycle
» Storage of Carbon in rocks –
• Long Term Inorganic cycle – best represented here
– From CO2 trapped in Ice Core measurements (Antarctic)
– Together all 3 cycles
• Influ. atm CO2 over
– Long Time scales
• CO2 vs Temp correlate – Spark a large debate . . ..
CO2
Avg. Earth
TEMP
13*C
Varying/time
Petit et al., 1999, Nature 399, 429
• Summary
– No Questions CO2 is on the Rise 300ppm
• Unlike never before
– Leading to Higher temperatures on earth
– What will happen?
– Major climate changes???
» More hurricanes, storms, floods etc.
» Quite possibly – only one way to find out
» Wait and see . . ..
SUMMARY- / Confirming your knowledge
• How does CO2 in the atmosphere influence the Earth’s Climate?
– Serves as a Greenhouse gas
• What holds more CO2 the Oceans or Atm?
– Oceans; thus small changes in ocean conditions 
• large effects on atmosphere, warming/cooling (climate change)
• Where is most of the earths carbon stored?
– Rocks (CaCO3) limestone
• CO2 & O2 undergo rapid changes via biological activity in Oceans from
– phytoplankton (photosythnesis) & animals (respiration); what do they do?
• CO2 is consumed (phytoplankton) O2 released
• O2 is comsumed (animals/zooplankton), CO2 is released
• Storage of Carbon in Oceans~ only understood by quantifying:
– The production (photosynthesis),
– The sedimentation
– Burial/subduction in ocean crusts
SUMMARY
– Humans have been adding Considerable CO2 to Atm for
• 100 years
– The world ocean has absorbed 48% of anthropogenic CO2
•  increasing Ocean acidity (lowered the pH)
• LONG TERMS RESULTS -- Not Clear?
• Speculative . . . But probable – real climate changes
How does this CO2/temp. change affect climate? To be continued...
• Lets get informed/Involved?
– Watch the Movie 90min
Inconvenient Truth Trailer
http://www.youtube.com/watch?v=wnjx6KETmi4
Controversial Inflection points
Minor issue – does cast doubt on presentation
-brought to light by nut jobs. ..
http://www.youtube.com/watch?v=4_aRKRyB7UE&feature=related
http://www.youtube.com/watch?v=UOqms6REmC8&feature=related
Will ask 2 basic Questions from about glaciers and worldwide temperature