How can Several Hundred Thousand Years of Temperature Data be Determined from Ice Core Samples?
Time for the Test!
Click on the button below to analyze the ice core your team has extracted in a mass spectrometer. You have already equilibrated several samples from an ice core in Greenland (GISP2) with carbon dioxide. You can now select the sample year you wish to analyze and run tests on that CO2.Then record the values for masses 44(12C16O2) and 46(12C16O18O).
Click on the button below to analyze the ice core your team has extracted in a mass spectrometer. You have already equilibrated several samples from an ice core in Greenland (GISP2) with carbon dioxide. You can now select the sample year you wish to analyze and run tests on that CO2.Then record the values for masses 44(12C16O2) and 46(12C16O18O).
The values that you recorded for mass 44 correspond to the abundance of the 16O isotope, and mass 46 corresponds to 18O. Divide the abundance of the 18O isotope by the abundance of 16O to determine the 18O/16O ratio. To convert your ratios into delta notation, use the formula below. Rsample is the ratio you have calculated experimentally, and Rstandard is the Vienna Standard Mean Ocean Water (VSMOW) value, which is 0.00200520. This value is based on the 18O/16O isotopic ratios of pure water.
δ18O = (Rsample - Rstandard⁄Rstandard) • 1000
Now you can estimate what the temperature was for the year you chose to analyze. Click below to view a graph that shows the correlation between delta 18O values and temperature in Greenland, and approximate the temperature based on your calculated delta 18O value. How do the different years compare?