Irish Independent: Global warming could lead to sea level rises of more than 20 feet — far higher than current estimates, and enough to swamp densely populated coastlines of north America and Europe, say scientists. A team of experts has calculated that if the West Antarctic Ice Sheet collapses — as many expect it to — the outcome will be worse than has been forecast. The sea level in the wake of the collapse is already projected to rise between 16 and 17 feet. The new research suggests the …