I was surprised to find the bishops writing about ice fields. But both Chile and Argentina have recognized claims on parts of Antartica, as well as some disputed claims.
Their concerns about shrinking ice fields, which they relate to global warming, are expressed in paragraph 87:
We likewise note the shrinking of ice fields throughout the world: dwindling ice in the Arctic, whose impact is now being observed in the flora and fauna of that ecosystem; global warming can also be felt in the thundering crackle of blocks of Antarctic ice that are reducing the glacier coverage of the continent which regulates world climate.
They conclude this section with a quote from Pope John Paul II.
Twenty years ago speaking from the tip of the Americas, John Paul II pointed out prophetically:
“From the Southern Cone of the American Continent and facing the limitless spaces of the Antarctic, I issue a cry to all those responsible for our planet to protect and preserve nature created by God: Let us not allow our world to be an ever more degraded and degrading land.”
Here is an English translation of the 2007 document from the Aparecida Conference.