Sea ice loss is one of the clearest signals of global warming.

Losing that much in just three years “is pretty incredible” and faster than anything seen before.

Sea ice also affects the polar ecosystem, including penguins and whales and seals.

Sea ice around Antarctica has shrunk to record low levels over the past few years, a new study suggests, following decades of expansion.

In recent years, “things have been crazy,” said Mark Serreze, director of the National Snow and Ice Data Center. He called the plummeting ice levels “a white-knuckle ride.”

Sea ice is frozen ocean water that melts each summer, then refreezes each winter. It floats on top of the ocean. Using satellite images, the study took a look at changes in Antarctic sea ice over the past 40 years.

Sea ice loss – especially in the Arctic but less so in the Antarctic – is one of the clearest signals of global warming, according to the National Climate Assessment.

Around Antarctica, sea ice averaged 4.9 million square miles in 2014. By 2017, it was a record low of 4.1 million square miles

The difference – about 770,000 square miles – covers an area three times the size of Texas. Losing that much in just three years “is pretty incredible” and faster than anything seen before, said study lead author Claire Parkinson, a NASA climate scientist.

Waleed Abdalati, a scientist at the University of Colorado, told the Independent that “the fact that a change this big can happen in such a short time should be viewed as an indication that the Earth has the potential for significant and rapid change.”

In addition to human-caused warming of the Earth's atmosphere and oceans, several factors – including the geography of Antarctica, the region's winds and air and ocean temperatures – affect the ice around Antarctica.

The National Snow and Ice Data Center said that even though sea ice occurs primarily in the polar regions, it influences our global climate and weather patterns around the world.

"Sea ice also affects the polar ecosystem, including penguins and whales and seals, petrels and albatrosses, krill and a whole range of additional animals and marine plant life," Parkinson told CNN.

The study was published in the peer-reviewed journal the Proceedings of the National Academy of Sciences.

Contributing: The Associated Press