how thick is the polar ice cap?

Answer 1

Pack ice is formed from seawater in the Earth's polar regions, and coverage increases during winter. In spring and summer, when melting occurs, the margins of the sea ice retreat. The vast bulk of the world's sea ice forms in the Arctic ocean and the oceans around Antarctica. The Antarctic ice cover is highly seasonal, with very little ice in the austral summer, expanding to an area roughly equal to that of Antarctica in winter. Consequently, most Antarctic sea ice is first year ice, up to 1 meter thick. The situation in the Arctic is very different (a polar sea surrounded by land, as opposed to a polar continent surrounded by sea) and the seasonal variation much less, consequently much Arctic sea ice is multi-year ice, and thicker: up to 3–4 meters thick over large areas, with ridges up to 20 meters thick.

Answer 2

Polar ice cap is about 10 - 12 ft. thick now but it has thinned
an average of 40% over just the last 40 or so years..

Answer 3

This is for the glacial caps, that what you want?
Depends where you are, the GISP 2 core hit rock at 3053m, 3028m on the GRIP core in Antarctica, the Vostok core went to 2546m.