(9)The methodology to calculate life-cycle greenhouse gas emissions for activities in the hydropower sector should reflect the specificities of that sector, including new modelling methodologies, scientific knowledge and empirical measurements from reservoirs worldwide. To allow accurate reporting on the net impact on greenhouse gas emissions for the hydropower sector, it is therefore appropriate to allow for the use of the G-res tool that is publicly available free of charge and has been developed by the International Hydropower Association in collaboration with the UNESCO Chair for Global Environmental Change.