June 2012

Teaching about Teaching about COCO22, Temperature, and Climate Change, Temperature, and Climate Change

Beth Caissie Beth Caissie 1, 21, 2

with collaboration from Julie Brigham-Grettewith collaboration from Julie Brigham-Grette11, Laura Schofield, Laura Schofield33, , Christina CiarametaroChristina Ciarametaro33, and Mort Sternheim, and Mort Sternheim11

11 UMass Amherst Geosciences and STEM Ed Institute; UMass Amherst Geosciences and STEM Ed Institute; 22 Iowa State University; Iowa State University; 33 Ipswich Middle SchoolIpswich Middle School

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• The Role of the Oceans

• 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?

The Carbon Cycle

IPCC. Climate Change 2007: Working Group I: The Physical Science Basis; Figure modified from Sarmiento and Gruber, 2006

Play the Carbon Cycle Game!

• Go to your assigned station• Roll the Die• Move (or don’t move) according to the sheet

at your station• Record what happened for EACH roll of the

die on your Itinerary• When you’ve rolled the die 10 times, come

up and record your trip on the board.

What causes this change in annual Carbon dioxide?

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

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Monitoring of CO2 and other Greenhouse gases around the world

All get similar measurements

Why?

Thermal drilling on Quelccaya, 2003

Drilling in Greenland

http://passporttoknowledge.com/polar-palooza/pp09a.php

Video podcast from Polar Palooza

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;

Matt Nolan, UAF

Fossil air!

Trapped in the ice;

records past atmosphere

Raynaud, 1992 Gases within bubbles = fossil atmospheric air

Firn-ice transition• Depth of transition depends on surfacetemperature 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

Activity•Students plot subset of either temperature or CO2 data from Vostok•Compile individual plots into 1 record•Overlay Temperature on CO2

Analysis•Define cyclicity of CO2 and temperature (amplitude, frequency)•Define “Normal” range of variability •Understand the relationship between GHG and temperature.

Forcing the Ice Ages: Milankovitch Cycles

http://deschutes.gso.uri.edu/~rutherfo/milankovitch.html

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 (1H2

16O) to 22 (2H218O)

“light water” “heavy water”

In paleoclimate studies…1H1H16O to 1H218O

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)

Ice Sheet

ocean 0

-10

-20-30

-40-5018O isotopic depletion

In Sea In Ice

Glacials = enriched 18O depleted 18O

Interglacials = depleted 18O enriched 18O

Evaporation of more 16 O

Ice Sheet

ocean

D isotopic depletiondepends on temp of source area,Distance and processes during precipitation

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