An international team of scientists announced Thursday they’ve successfully drilled one of the oldest ice cores yet, penetrating nearly 2 miles (2.8 kilometers) to Antarctic bedrock to reach ice they say is at least 1.2 million years old.Analysis of the ancient ice is expected to show how Earth’s atmosphere and climate have evolved. That should provide insight into how Ice Age cycles have changed, and may help in understanding how atmospheric carbon changed climate, they said.“Thanks to the ice ...