Science Facts - Vostok Ice Core Overview

Ice core data is available for free on the internet. Normally, there are already a number of graphs showing some of it. However, I have a lot of questions, and I could never find plots showing exactly what I wanted. Therefore, I wrote my own software (provided here for free).

In general, my software plots their data without modification. However, in some cases I wanted to compare two plots where the range (minimum and maximum values) of the two series made direct comparison too difficult. In those cases, I changed the scale and baseline of one of the plots. (This is also user controlled, but I wanted the defaults to be scaled.)

There is a basic problem when plotting many different types of data on the same graph. For instance, CO2 is measured in ppmv (parts per million by volume) and temperature is in degrees minus some arbitrary average (referred to as delta degrees). As a result, I save simply labeled the y-axis in a generic manner.

This is an image of IceCorePlots_Vostok.exe ver 0.1.

This program reads several data files (included in the zip file) and plots the data. The y-axis does not have a specific label because it is used for all the series.

The graph allows you to select between 3 different x-axes - depth, age of the ice, age of the air. The dust data is only associated with the age of the ice and, therefore, is not displayed when the data is plotted verse depth. When age of air is selected, the main change is that the CO2 data is shifted.

The Set Chart Properties button pops up the same dialogbox as right clicking a series label. The main difference is that right clicking the label displays the dialogbox with that series already selected.

The dust and delta-temperature data are scaled and offset to allow simple comparisons with the CO2 data. However, you can modify these the Chart Properties dialogbox.

The raw data, from NOAA, is available in the zip file. If you don't like my plots, you can make your own.

One of the surprises was that there is no CO2 data after 2,342 BP. This is one of the reasons that many people don't accept the "ice core" data as showing ... whatever. It really does not overlap with current data.

Eventually, I plan to also include Greenland data because it snows more there and, therefore, the lag between ice age and air age will be less. But more to the point, the CO2 data will not end more than 2,000 years ago.

Author: Robert Clemenzi
URL: http:// / Science_Facts / IceCores / Overview.html