ZOL 355 Lecture 15 Outline of Previous Lecture II CO2 in our atmosphere III CO2 accumulating in the oceans a Pycnocline b Organic vs inorganic carbon Outline of Current Lecture I II III IV V Atmospheric CO2 and the Carbon cycle The Ocean sink Biological cycle Geological cycle Carbon Isotopes Current Lecture I II III IV V VI VII VIII IX X atmospheric CO2 and the Carbon Cycle photosynthesis and r controlled atmospheric CO2 increases are anthropogenically driven Can ecosystem moderate CO2 in the atmosphere less than 1 of the PP reaches the sink The ocean sink Carbon must be transferred to long term storage biological cycle a residence time 2 years to 10 000years b 3x10 12 tons c detritus degrading organic material gets incorporated into sedimentssediment soil organic matter geological cycle long term a thousands to millions of years b 6x10 15 tons small leak between cycles Anthropogenic disruption of the geological cycle results in rising atmospheric CO2 The impact is a function of flux and residence time a flux net transfer of material into or out of a reservoir unit time i molesC yr ii gC yr b Residence Time amount of a substance in a reservoir divided by rate of its supply or removal XI XII i or ii amount of a substance in reservoir divided by flux iii gC gC yr years quantifying the impact of increased CO2 emissions a Look at slide b Translates into an increased ocean acidification and weakening of the ocean CO2 sink Increased mixing events storms could release lots of CO2 to the atmosphere Some think that increased winds and intensity of storms will occur with global warming identifying the origin of increasing atmospheric CO2 via carbon isotope values a evidence of anthropogenic origins of CO2 i C isotope values 1 C12 stable 2 C13stable 3 C14 radioactive b C isotope ratios i 13C 12C R ii ratio of the abundance of C13 vs C12 c C isotope values indentify sources of C i Reservoirs that differ Atm CO2 marine carbonate bicarbonate are much higher d Inorganic C all reservoirs have C isotope values that is great than 10 e Organic reservoirs are less than 10 f If Co2 derives from inorganic Carbon it holds 10 but taking a log at 25 the isotope will hold that value Were taking a Reservoir from organic matter with a 10 changed to CO2 holds the same isotope value which is a low value In twenty years we ve changed the reservoir by 18