Atmospheric CO2 & Temperature – Julie Brigham-Grette and Beth Caissie what is normal? Presented by Julie Brigham-Grette and Beth Caissie July 2010

CO2 and Temperature—What is Normal? Concepts to Address before you begin Climate vs. Weather Greenhouse Gasses The Carbon Cycle Play the game? Photosynthesis and Decomposition Concepts to grasp During the Activity How much of a change in CO2 concentration and other GHGs is natural? What is the normal range of CO2 and temperature variability? How is normal defined in this context? What is the relationship between CO2 and global temperatures?

Season Change in the Biosphere

What causes this change in annual Carbon dioxide?

Seasonal changes cause up/downs in CO2 in the atmosphere http://www.esrl.noaa.gov/gmd/ccgg/trends/ http://www.esrl.noaa.gov/gmd/ccgg/trends/ Seasonal changes cause up/downs in CO2 in the atmosphere Especially driven by Northern Hemisphere. Spring - photosynthesis drops CO2, Fall - decomposition causes increase in CO2

Monitoring of CO2 and other Greenhouse gases around the world All get similar measurements Why?

http://www.esrl.noaa.gov/gmd/ccgg/trends/

Global View CO2 http://www. esrl. noaa

Thermal drilling on Quelccaya, 2003 The ice is extruded from a core barrel – either thermal or electromechanical – then logged, slid into tubes, and packed into insulated boxes for frozen transport. Almost all the analyses take place back in clean rooms – so if the ice is lost, so is the information. Thermal drilling on Quelccaya, 2003 9

Drilling in Greenland Video podcast from Polar Palooza http://passporttoknowledge.com/polar-palooza/pp09a.php

Trapped in the ice; records past atmosphere Matt Nolan, UAF Fossil air! Trapped in the ice; records past atmosphere Summit Station, Greenland photo by Michael Morrison, GISP2 SMO, University of New Hampshire; NOAA Paleoslide SetCore: Eric Cravens, Assistant Curator, U.S. National Ice Core Laboratory;

Gases within bubbles = fossil atmospheric air Raynaud, 1992 Gases within bubbles = fossil atmospheric air

• Depth of transition depends on surface Firn-ice transition • Depth of transition depends on surface temperature and accumulation rate • Camp Century, Greenland: ~68 m below ice sheet surface • Vostok, Antarctica: ~100 m below ice sheet surface Low precip. and cold = long time to make ice High precip. and warm = short time to make ice

Plot by hand on graph paper, Plot on computer using Excel Classroom options: Plot by hand on graph paper, Plot on computer using Excel Overlay Temperature on CO2 Analysis: Defining amplitude, frequency, periodicity Defining Normal? Understanding the relationship between Greenhouse gases and temperature. Instructions for Excel on website

wikipedia art

1H 2H (Deuterium) 3H (tritium) 99.98% 0.016% (bombs) Oxygen (8 protons) 16O 17O 18O 99.8% 0.04% 0.2% Hydrogen (1 proton) 1H 2H (Deuterium) 3H (tritium) 99.98% 0.016% (bombs) So, can make 9 isotopic combinations of H2O, e.g., 18 (1H216O) to 22 (2H218O) “light water” “heavy water” Isotopes are any of the different chemical species of a chemical element each having different atomic mass (mass number). Isotopes of an element have nuclei with the same number of protons (the same atomic number) but different numbers of neutrons. Therefore, isotopes have different mass numbers, which give the total number of nucleonsﾑthe number of protons plus neutrons. In paleoclimate studies…1H1H16O to 1H218O

Expressed in per mille (0/00) General Equation:  18O = 18O/16O sample - 18O/16O standard x 1000 18O/16O standard Expressed in per mille (0/00) Negative values = lower ratios = isotopically lighter (less 18O than 16O) Positive values = higher ratios = isotopically heavier (more 18O than 16O)

Glacials = enriched 18O depleted 18O d18O isotopic depletion -50 -40 -30 -20 Evaporation of more 16O Ice Sheet -10 ocean In Sea In Ice Glacials = enriched 18O depleted 18O Interglacials = depleted 18O enriched 18O

depends on temp of source area, dD isotopic depletion depends on temp of source area, Distance and processes during precipitation Ice Sheet ocean The isotopic composition of water, and in particular the concentration of the heavy isotope of oxygen, 18O, relative to 16O, as well as 2H (deuterium) relative to 1H, is indicative of the temperatures of the environment. During cold periods, the concentration of less volatile 2H (18O) in the ice is lower than during warm periods. The reason for this is that at lower temperature, the moisture has been removed from the atmosphere to a larger degree resulting in an increased depletion of the heavier isotopes. Isotopic ratios are used to model temperature, at Vostok; empirically this is roughly: Temperature (deg-C) = -55.5 + (δD + 440) / 6 http://eesc.columbia.edu/courses/ees/climate/labs/vostok/ See also http://www.globalchange.umich.edu/gctext/Inquiries/Inquiries_by_Unit/Unit_8a.htm

mixed sources for data

http://earthobservatory. nasa. gov/Library/CarbonCycle/carbon_cycle4 http://earthobservatory.nasa.gov/Library/CarbonCycle/carbon_cycle4.html