Building a curtain across the Jakobshavn glacier in Greenland – a suggestion to slow it melting – is estimated to take a minimum of 30 years and be expensive. A quick, albeit unsightly, fix would be to sink two or more large ships across the front of the glacier, which would block the influx of warmer water that is quickly melting the ice. Plenty of ships are waiting to be scrapped, so the owners may pay to be rid of them. If necessary, filling the ships with rock would ensure they remain in place. Depending on the depth, other ships could be gently sunk on top to block the current all the way to the surface. Calving icebergs would be held back by the temporary dam, hopefully protecting the glacier further. credit this idea to Jim McHardy, New Scientist letters 10 December 2022