Secretary-General Antonio Guterres says there has been a lack of leadership to address global warming.
Prediction is the result of a new statistical model using weather trends dating back over 100 years.
Increased costs of products will be passed on to consumers and farms could be hit with emissions rules.
That's according to University of Auckland research that mapped shoreline change of Tuvalu's 101 islands across its nine atolls.
With world leaders meeting in Germany this week to discuss climate change, sea level rise will definitely be on the agenda.