Definitions for column headers......

• Depthis quoted in meters. There are still small adjustments being made to the depth scale by the Science Coordination Office for the Siple Dome core.

• MED (mm)is the mean equivalent diameter of all bubbles which were counted and sized in the section. The area in pixels is converted into an equivalent diameter via the following formula: ED = (4/pi * area)^1/2. This is the standard which I use to compare bubble sizes. If you need the bubble size in some other measure, you will probably find it in the data files.

• 95% CLis the 95% confidence limit around the mean in column 2. This value is plotted as the error bar on the chart for these data.