In your own question you admit that the world is warming:
"...this ice is expanding rather than shrinking in a warming world."
Explanations for it from the same article you reference:
”In a new study in the Journal of Climate, Zhang finds both strengthening and converging winds around the South Pole can explain 80 percent of the increase in ice volume which has been observed. “The polar vortex that swirls around the South Pole is not just stronger than it was when satellite records began in the 1970s, it has more convergence, meaning it shoves the sea ice together to cause ridging,” the study’s press release explains. “Stronger winds also drive ice faster, which leads to still more deformation and ridging. This creates thicker, longer-lasting ice, while exposing surrounding water and thin ice to the blistering cold winds that cause more ice growth.”
"A recent study by Lorenzo Polvani and Karen Smith of Columbia University says the model-defying sea ice increase may just reflect natural variability. If the increase in ice is due to natural variability, Zhang says, warming from manmade greenhouse gases should eventually overcome it and cause the ice to begin retreating. “If the warming continues, at some point the trend will reverse,” Zhang said.
However, a conclusion of the Barnes study is that the recovery of the stratospheric ozone layer – now underway – may slow/delay Antarctic warming and ice melt. Ultimately, it’s apparent the relationship between ozone depletion, climate warming from greenhouse gases, natural variability, and how Antarctic ice responds is all very complicated. In sharp contrast, in the Arctic, there seems to be a relatively straight forward relationship between temperature and ice extent. Arctic sea ice has *not* recovered. Thus, in the Antarctic, we shouldn’t necessarily expect to witness the kind of steep decline in ice that has occurred in the Arctic. “…the seeming paradox of Antarctic ice increasing while Arctic ice is decreasing is really no paradox at all,” explains Climate Central’s Lemonick. “The Arctic is an ocean surrounded by land, while the Antarctic is land surrounded by ocean. In the Arctic, moreover, you’ve got sea ice decreasing in the summer; at the opposite pole, you’ve got sea ice increasing in the winter. It’s not just an apples-and-oranges comparison: it’s more like comparing apple pie with orange juice.”
You did read this article, didn't you, before you posted it? The article's content is in direct support
of global warming...