Scientists are stumped after learning that Antarctica is missing a gigantic amount of sea ice that measures up to four times the size of Texas. It's currently the middle of winter in the Southern Hemisphere, a time when sea ice is expected to expand. However, Antarctica has witnessed a drastic decrease. Sea ice is said to be controlled by a balance between the atmosphere and oceans each year. Dr Steve Rintoul, CSIRO Fellow and Research Team Leader, explained [via the Sydney Morning Herald]: "The factors that influence sea ice include winds from north to south are stronger than usual which pushes sea ice towards Antarctica and restricts how far sea ice spreads. "The warmer water means there is less sea ice, and even things like melting the surface melt can alter sea ice forming." Data from the National Snow and Ice Data Center (NSIDC) shows that the ice was more than 2.6 million square kilometres below the 1981 to 2010 average. While it's natural for levels of sea ice to change, Dr Rintoul noted that this is the lowest amount recorded in the last 40 years. Sign up for our free Indy100 weekly newsletter Despite factors such as the atmosphere playing its part, the exact reason behind the decline is baffling scientists. "It is stunning," Dr Rintoul said. "The fact is we don’t know why [we’ve got record low sea ice]. "No one predicted this, we don’t understand why this season is as low as it is." Eric Rignot of NASA's Jet Propulsion Laboratory and the University of California, Irvine told Axios that it's too early to determine how responsible climate change is to this year's sea ice decline. He went on to note that when declines started in 2016, researchers couldn't say whether it was part of a larger trend. "Now, we can say with a bit more certainty that this is not anomalous behaviour — it's a change of state," he told the outlet. Have your say in our news democracy. Click the upvote icon at the top of the page to help raise this article through the indy100 rankings.