How Do Ice Cores of Glaciers Tell Us about Past Climates?
ES2105  Identifying Warming and Cooling Periods

Two markers have been placed on the graph. One marks the peak of a strong warming trend at 133,000 years ago, and the other marks the minimum temperature reached at the end of a cooling trend 64,000 years ago. Carefully examine the graph and identify a peak that marks the end of another strong warming trend and a dip marking the end of another strong cooling period.

  !   Drag the arrows from the tool palette onto the graph to mark these two points. Use another piece of paper to record the ages of all four marked points.

 
Source: Jouzel et al, 1987.
Average temperatures determined from the Vostok, Antarctica ice cores.

 
     
   

 Step:   1   2   3   4   5   6   7   8   9   10