Ice samples show climate capable of abrupt changes

Samples drilled from Greenland’s ice sheets have thrown up initial clues that our climate is capable of very rapid and rather abrupt changes, according to an international team of scientists.

Such evidence is provided by the accumulation of layers of ancient snow, compacting to form the ice—sheets we see today.

Each ice layer can reveal past temperatures and even evidence for the timing and magnitude of distant storms or volcanic eruptions.

Until now such temperature records from Greenland have covered only the last 100,000 years or so, the journal Science reports.

An international team, led by Stephen Barker of Cardiff University, has produced a prediction of what climate records from Greenland might look like over the last 800,000 years, according to a Cardiff statement.

Barker is reported saying: “Our approach is based on an earlier suggestion that the record of Antarctic temperature variability could be derived from the Greenland record.

“However, we turned this idea on its head to derive a much longer record for Greenland using the available records from Antarctica,” added Baker.

The research demonstrates that abrupt climate change has been a systemic feature of Earth’s climate for hundreds of thousands of years and may play an active role in longer term climate variability.