The existence of a heavier layer of greenhouse effect gases at the level of the entire planet triggered significant climate changes. The paper intends to present the main environmental indicators elaborated by various specialised international bodies, and the models used by different governmental or non-governmental European bodies for studying the impact of greenhouse effect gas emissions on climatic changes or economic development. Also, a comparative analysis was made about the performance indicators obtained by means of differing models for forecasting greenhouse effect gas emissions by highlighting the information advantages/disadvantages in elaborating strategies and policies for limiting the negative effects.