- SF6 emissions have increased from 3.6 E-6 kt in 1990 (4.1 E-6 kt in 1995) to 5.4 E-6 kt in 2018. Distribution of GHG emissions by gas in 2018Nationally Determined Contribution Directorate of the Environment Evolution of GHG emissions by gas between 1990 and 2018Nationally Determined Contribution Directorate of the Environment 2.2 Objectives for the reduction of greenhouse gas emissions 2030 The Principality of Monaco has set itself the objective, within the framework of this Nationally Determined Contribution, of reducing its greenhouse gas emissions by 55% by 2030. Nationally Determined Contribution Directorate of the Environment 2.3 Main Policies and Measures To achieve its objectives by 2030, the Principality of Monaco has already implemented important policies and measures.