Ice Core and Vostok Data Questions
Part A: Ice Age versus Gas Age
1. Which is usually older based on depth, the gas or the ice?
2. Why do the two age curves differ?
3. How much difference is there at a depth of 1000 meters?
Part B: Temperature based on Deuterium Ratio
4. What is deuterium?
5. Deuterium is used to determine past temperature because of its relationship with what other molecule? What
are the different isotopes and which isotope is present in greater concentrations in glaciers during ice ages?
6. How many degrees has climate varied in the past, as indicated in these data?
7. Approximately when did the last glacial period begin and end? When did the last interglacial time period begin
and end? Within the most recent glacial period, what were the highest and lowest delta temperatures? What do
you think your hometown might have looked like at these times?
Part C: Past Concentrations of Carbon Dioxide
8. The data for CO2 concentrations dated back to 1900 years ago. During the time period of 1900 years ago to
180000 years ago, what appears to be the maximum amount of CO2 found in the atmosphere?
9. Below is the recent data taken from the Mauna Loa Observatory (http://www.esrl.noaa.gov/gmd/ccgg/trends/).
What is the current amount of CO2 in the atmosphere?
10. Has the earth ever experienced this amount of CO2 based on the Vostek data?
Part D: Carbon Dioxide (CO2), Methane (CH4), and Delta Temperature (ΔT)
11. Note the time of the major warming events in the history of Earth. Then look at how CO2 and CH4 change during
the same time. From the data provided in this lab, can you tell which changes first, temperature or greenhouse
gas (CO2, CH4) composition? (Note the direction of the x-axis.) Suggest reasons why it could work either way.