Antarctic meltdown
The West Antarctic Ice Sheet (WAIS) contains almost a sixth of all Antarctica's ice. Current evidence shows it may be badly affected by climate change.
The largest glacier in the WAIS, the Pine Island glacier, is already melting and retreating. If the entire sheet collapses into the ocean, global sea levels could rise by a whopping five metres - enough to drown many major cities.
| 
A crack in the Pine Island glacier, captured by the ASTER satellite in 2000. A large iceberg later broke off the glacier.
NASA/GSFC/MITI/ERSDAC/JAROS |
|
