We can use three concepts to define how we can achieve a positive outcome from the COP21 in Paris.

The first one is the Two-level game theory introduced by Robert Putnam in the late ‘80s: in the last decade, climate has been transformed from an international issue to a domestic issue and the connection between these two levels is a key feature in climate negotiations.

Robert Keohane provides us the second concept with his Complex regimes theory, by which we can understand why a top-down solution is not enough to address climate related challenges.

The third concept is taken by Robert Lucas’ Rational expectations theory, we should improve a mechanism aiming at making expectations of several actors to converge.

Laurence Tubiana (Special Representative of the French Minister of Foreign Affairs for the 2015 Paris Climate Conference, COP-21, and French Ambassador for Climate Negotiations) took part in the opening session of ROME2015 – SCIENCE SYMPOSIUM ON CLIMATE with this video message from Paris.