To get a view on global temperatures that long ago, the researchers studied 73 sediment and polar ice samples, taken from all over the globe. (edition.cnn.com)
On a trip in the 1980s, the team had to bring back ice samples in water bottles because there was no way to keep them frozen. (discovermagazine.com)
Their food stays fresh in a freezer that is also used to store ice samples. (discovermagazine.com)