Content References

• Key Idea 4: Natural Isotopic Variability, Page 4: Coplen, Tyler B.;Holden, Norman E. Atomic Weights: No Longer Constants of Nature. Chemistry International. March-April 2011, 33. http://www.iupac.org/publications/ci/2011/33 02/2_coplen.html (accessed July 23, 2012).

Definitions: Adapted from:

• IPCC, 2007: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M.Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.
• IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8. Doi:10.1351/goldbook .
• Mahaffy, P. G.; Bucat, B.; Tasker, R.; Kotz, J. C.; Treichel, P. M.; Weaver, G. C.; McMurry, J. Chemistry: Human Activity, Chemical Reactivity, 1st Canadian Edition; Nelson, 2011.

Except for:

• Deep time definition: “Deep Time.” Oxford Dictionaries. https://en.oxforddictionaries.com/definition/ us/deep_time (accessed June 14, 2012).
• Stable isotope definition: Holden, Norman E.; Tyler B. Coplen. “The Periodic Table of Isotopes for the Education Community.” DivCHED CCCE: Committee on Computers in Chemical Education. June 2012. Http://www.ccce.divched.org/spring2012conf chemp6 (accessed June 14, 2012).
• Radioactive isotope definition: Holden, Norman E.; Tyler B. Coplen. “The Periodic Table of Isotopes for the Education Community.” DivCHED CCCE: Committee on Computers in Chemical Education. June 2012. Http://www.ccce.divched.org/spring2012conf chemp6 (accessed June 14, 2012).

Image Credits: Sources for images are as follows:

Introduction

• Ice core extraction: From the British Antarctic Survey.
• Heavy and light ice: By Theo Keeler.

Key Idea 1: Atomic Structure

• Windmills: By ntitanium - http://www.sxc.hu/photo/609048.
• Medicine: By Leonardini - http://www.sxc.hu/photo/1238929.
• Clouds: By fsstudio - http://www.sxc.hu/photo/1425668.

Key Idea 2: Defining Isotopes

• Clouds: By saavem - http://www.sxc.hu/photo/1235086.
• Mass Spectrometer: Mass Spectrometer schematic diagram accessed 22 July 2014 at http://commons.wikimedia.org/wiki/File:Mass _Spectrometer_Schematic.svg

Key Idea 3: Percent Abundance of Isotopes and Atomic Weight

• Bamboo with water droplets: By Skippy3E - http://www.sxc.hu/photo/1377707.
• Heavy and light ice: By Theo Keeler.

Key Idea 4: Natural Isotopic Variability

• Ötzi: Copyright of South Tyrol Museum of Archaeology - www.iceman.it.

Key Idea 5: Isotopes and Climate

• Ice core montage: Copyright of Reto Stockli, NASA GSFC; accessed at http://earthobservatory.nasa.gov/Features/ Paleoclimatology_IceCores/.
• Forest: By Agrid - http://www.sxc.hu/photo/860528.
• Industry: By CMSeter - http://www.sxc.hu/photo/898100.
• Iceberg: By lyeager - http://www.sxc.hu/photo/835129.