The sea ice cloaking the Arctic Ocean hasn’t retreated to the lowest level since satellite records are kept despite the fact that most scientist predicted that it would. Polar scientists confirmed on Tuesday that this year’s arctic ice recession did not match 2007’s.

However, the level is still very, very low. According to scientists at the National Snow and Ice Data Center (NSIDC), this summer’s polar ice level was 33 percent below the average extent since 1979, the year when satellite images helped scientists keep track of the sea ice. Scientists underlined once again that all things involved in the equation are indicating towards an ice-free Arctic Ocean and this could happen in just a few decades.

There are two types of ice in the Arctic Ocean. The seasonal ice, which melts and forms again every year, and the sea ice, which is a thicker layer, also formed by frozen water, but which remains frozen even through the summer. The sea ice is far more important and it used to cover about 60 percent of the Arctic.

But now, only half of this important layer of ice still floats in the Arctic Ocean according to a report issued Tuesday by NASA and the NSIDC at the University of Colorado.

"According to NASA-processed satellite microwave data, this perennial ice used to cover 50 to 60 percent of the Arctic, but this winter it covered less than 30 percent," a NASA statement said.

This year’s 33% below-average sea ice level is the second-lowest in recorded history after the 39% below average recorded last year.

NASA and the NSIDC are currently working on a study that also focuses on the causes of this substantial change. The study will probably be released in early October, NASA said.