Researchers investigated the content of argon, krypton and xenon in air bubbles trapped in Antarctic ice. As the oceans warm up, crypton and xenon are released from the water, and scientists know what amounts are released at individual temperatures. Thus, the ratio of gases to one another allows the calculation of the average global temperature of the oceans. Ice cores were collected from the West Antarctic Lądolód, where data from the last 100,000 years were obtained, with layers allowing for dating to 50 years. As the atmosphere is stirred for not more than a month, the measurements gave a global average temperature response. Researchers focused on data from 22 to 8 thousand years ago, and the temperature was determined for 250-year periods.
