Targeted geoengineering for ice sheets

In recent years, scientists have proposed targeted geoengineering for ice sheets to enhance their stability and slow their mass loss, reducing their contribution to sea level rise at source. It promises to buy hundreds of years to combat climate change and protect coastlines. Ice sheet geoengineering works mainly on ice bottom and ice shelf-ocean interface. The main approaches include: 1) draining or freezing the water from the bottom of the glacier to dry the ice bed and enhance the friction of the glacier bottom; 2) making artificial islands in the sea to support floating ice shelves; 3) building an underwater barrier in front of the ice shelf to keep warm water from reaching the ice bottom to slow its melting. Ice sheet geoengineering includes numerical simulation, scheme design, engineering test, and political and legal research. International research teams have been carrying on numerical simulation and scheme design research. The research of engineering experiment and politics and law has not started yet. This paper predicts that the difficulty ladder of engineering test may be from laboratory test to small scale field test, then to outlet glaciers of Greenland ice sheet, and finally to outlet glaciers of Antarctic ice sheet. Targeted geoengineering for ice sheets is likely to become a new field of global change research in 21st century.