"Ice sheets contain enormous quantities of frozen water. If the Greenland Ice Sheet melted, scientists estimate that sea level would rise about 6 meters (20 feet). If the Antarctic Ice Sheet melted, sea level would rise by about 60 meters (200 feet)."
http://nsidc.org/cryosphere/quickfacts/icesheets.html
Thank you. Let me do some simple math with the numbers your source provided:
Total area of ice sheets, North and South = 6M Sq Mi
Total surface area of earth = 200M Sq Mi
Total surface area of water on the earth = 140M Sq Mi
Percentage of ice sheet area to total water area = 4.3%
For 4.3% of the earth’s surface to produce a combined total of 220 feet of sea level change would require an ice sheet with a average thickness of 5,116.2 feet.
That is significantly thicker than the thickest known ice shelves in Antartica (around 3,000 feet), but average thickness is less than half of that. It most certainly is much less that the artic cap.
I rounded figures conservatively, and you can apply earth’s curvature instead of figuring in linear miles, but that only makes the numbers worse for your argument.