Meets: Tuesdays and Thursdays 9:30-10:45 am, Benson Earth Sciences 355 Course description: Examines the chemical, biological, geological, and physical processes impacting (and impacted by) the chemistry of the oceans. Topics include: major chemical inputs (riverine, eolian, hydrothermal) and outputs; the large-scale interdependence of nutrient distributions and biological productivity; the marine carbon cycle and its long-term control on atmospheric CO2; the chemistry of marine sediments, including post-depositional alteration (diagenesis); chemical tracers of modern ocean circulation; and paleochemical methods for inferring past ocean circulation and climate change. This will be a lecture course. The required textbook is Chemical Oceanography by Frank Millero (3rd Edition), which will be supplemented by readings from other books and from the research literature. Grading: 40% homework, 25% midtern exam, 25% final exam, 10% class participation. Undergraduate and graduate homework assignments and exams will be slightly different, and the two groups will be evaluated separately. Homework: Six homework assignments will allow students to apply what they have learned in class to practical problems. Math will generally be limited to algebra, plus a little calculus. Critical reading and thinking skills will also be evaluated through questions based on the scientific literature. Homework assignments are to be handed in during class (generally one week after being assigned), and late assignments will lose 10% credit per day.
“The chemistry of the oceans is the chemistry of life writ large” -David Archer
Professor: Tom Marchitto, tom.marchitto@colorado.edu
Office Hours: Tuesdays 11:00-12:00 in Benson 435, or by appointment
Undergrad enrollment limited to juniors and seniors
3 CreditsClass Schedule and Reading
click on lecture title for PowerPoint file (password protected)
T 9/5:
Upper ocean circulation
introduction, winds, wind-driven currents, upwelling
No reading
Th 9/7:
Deep ocean circulation
temperature/salinity/density, meridional overturning circulation, water masses
Read Section 1.3
T 9/12:
Composition of seawater: Major elements
salinity, conservative and quasi-conservative behavior
Read Sections 2.1, 2.2.1, 2.3, 2.6, 2.7
Th 9/14: Minor and trace elements
d0/d10/transition cations, non-conservative behavior, biological uptake
Read Sections 3.1, 3.3, 3.4
Nozaki's compilation of dissolved elements in the Pacific
MBARI periodic table of elements in the ocean
T 9/19:
Minor and trace elements; Elemental sources and sinks
steady state and residence time, river/eolian/hydrothermal inputs, outputs
Read Sections 3.2, 3.5
Th 9/21:
Properties of water and ionic interactions
hydrogen bonds, ion-water interactions, ion-ion interactions
Read Sections 4.1, 4.2; Skim rest of Chapter 4
T 9/26:
Air-sea exchange and dissolved oxygen
Henry's law, exchange rates, apparent oxygen utilization
Read Sections 6.1, 6.2, 6.3, 6.4, 6.6
Th 9/28:
Carbonate system in seawater
pH, carbonate equilibria, carbonate parameters
Read Sections 7.1, 7.2, 7.3, 7.4, 7.5
Good book for more details: CO2 in Seawater: Equilibrium, Kinetics, Isotopes by Zeebe and Wolf-Gladrow (2001), on overnight reserve in INSTAAR Information Center
Carbonate system calculator (Excel)
Carbonate system math (Matlab)
T 10/3:
CaCO3 cycling
coccoliths/foraminifera/pteropods, saturation states, lysocline/CCD
Read Section 7.6
Th 10/5:
Anthropogenic CO2 invasion
pCO2, carbon cycle, Revelle factor, impact on CaCO3 saturation
Read Sections 5.3, 7.7, 9.2
Supplemental reading: Sabine et al. (2004) (pdf)
Supplemental reading: Feely et al. (2004) (pdf)
1st Homework due
T 10/10:
Biological primary production
photosynthesis, gross/net/new/recycled production, Redfield ratios, trace metal biogeochemistry
Read Section 9.1
Th 10/12:
Organic matter in the water column
POM, DOM, organic compounds
Read Section 9.4
2nd Homework due
3rd Homework (Word)
T 10/17:
Nitrogen and phosphorous cycles
phosphate, nitrate, N fixation, denitrification
Read Sections 8.2, 8.3
Th 10/19:
Stable isotopes of C and N
d13C, air-sea d13C, d15N
3rd Homework due
T 10/24:
Mixing time tracers
14C, tritium, 3He, CFCs
Read Section 1.5
Th 10/26: Midterm Exam
T 10/31: U-series radionuclides
Th 11/2: Marine sediments
T 11/7:
Pore water chemistry and diffusion
Reading from Marine Geochemistry on reserve in Geology library
Th 11/9:
Bacterial oxidation of organic matter in sediments
Reading from Treatise on Geochemistry on reserve in Geology library
4th Homework due
5th Homework (Word)
T 11/14:
Fe, Mn, and S redox cycles
Reading from Marine Geochemistry on reserve in Geology library
Th 11/16:
Hydrothermal systems
5th Homework due
T 11/21: Holiday - No Class
Th 11/23: Holiday - No Class
T 11/28: History of ocean chemistry and the rise of cyanobacteria
Th 11/30:
Cenozoic weathering and atmospheric CO2
Reading from Treatise on Geochemistry on reserve in Geology library
T 12/5: Chemical paleoceanography: temperature and global ice volume
Th 12/7:
Chemical paleoceanography: glacial atmospheric CO2
6th Homework due
T 12/12: Fall AGU - No Class
Th 12/15: Fall AGU - No Class
Final Exam: Monday December 18, 9:30-noon, Benson 155
Key to grad version of Midterm Exam (undergard version was basically the same but shorter). Answers given are only the key points I was looking for. In reality, you often needed to write more explicit sentences demonstrating understanding.
Key to homeworks 5 and 6 (not numerical answers, but how to solve).