Digging for Treasure

by Tamsin Gray     Department: Earth

 
Yesterday I set out to dig up a piece of history. I wasn't looking for ancient ruins or even dinosaur bones, just plain old snow.

Why? Because Antarctic snow and ice contains a treasure trove of information about past climates. Everyone wants to know how the climate is going to change in the future but before we can predict the future, first we need to understand the past. Trapped in between the buried grains of snow and ice are little air pockets - bubbles of the atmosphere as it was tens, hundreds, thousands, even millions of years ago. The snow itself contains a wealth of information too; the chemistry of the snow depends on the temperature at the time that it fell.

This means snow and ice can tell us what the climate was like long before there were hi-tech instruments or meteorologists in Antarctica observing the weather.

So that's why I was digging. And there was a lot of digging (the deeper you dig, the further back in time you go). Still, my samples pale in comparison to the longest ice core to date...almost 2 miles of ice going back 800,000 years!

Here you can see me standing in the hole with the surface way above my head. To keep the samples clean I had to wear a full sterile suit, gloves and a mask but in temperatures of 15 below, I was pretty chilly, even under all that.

So far, Antarctic ice has revealed many interesting patterns in the climate. For example, deep ice cores have shown that at times in the past when there was more carbon dioxide in the atmosphere in the air, the earth was warmer (and when there was less carbon dioxide, temperatures were cooler). This strong correlation between carbon dioxide and temperature is at the heart of modern day climate change: we pump carbon dioxide into the atmosphere and take three guesses at what's going to happen...

Follow this link to hear from the experts about exciting ice core discoveries..

One last thing, I couldn't possibly end this entry without sharing a glimpse of my visit to the local Emperor penguin colony last week (to see more cute baby penguins, click here).

Tags: carbon dioxide, climate change, ice core, penguin, snow

+ Add Comment