Miami and New Orleans face greater sea-level threat than already feared

Twin studies reveal that acceleration' of sea-level rise under way, leaving southern US cities in even greater peril

Coastal cities in the southern US, including Miami, Houston and New Orleans, are in even greater peril from sea-level rise than scientists already feared, according to new analysis.

What experts are calling a dramatic surge in ocean levels has taken place along the US south-eastern and Gulf of Mexico coastline since 2010, one study suggests, an increase of almost 5in (12.7cm).