That's because the continent's ice sheets hold deeply buried air bubbles that can tell researchers a lot about what Earth's atmosphere was like thousands and even millions of years ago. In particular, their studies have shown that the amount of carbon dioxide in Earth's atmosphere has risen rapidly in the industrial era. That's a concern because many researchers believe carbon dioxide acts as a global warming gas, trapping heat near the planet's surface and causing long-term changes in climate. While the change of weather could be good news for some people, it could be disastrous for others. If warmer temperatures were to melt Antarctica's ice caps, for instance, researchers estimate that the global sea level would rise an average of 230 feet, flooding most coastal cities and drowning places like New York, London, and Hong Kong.
Some scientists say it's too early to see such signs of global warming.
Maritime officials fear the mother berg may eventually give birth to hundreds of calves, each of which could pose a substantial threat to cargo and passenger vessels. Many researchers believe more giant bergs are on their way as Antarctica's massive ice sheets melt back due to warmer temperatures, but that could take a very long time. Scientists recently estimated that it could take 7,000 years for the giant West Antarctic ice sheet to eventually disappear.