 He personally briefed several heads of state, many ministers and CEOs about climate issues, and has been or is member of several international scientific advisory or editorial boards (EU FP7 Research Programme, Dutch Climate Research Programme, Météo-France, EU JPI-Climate TAB, Royal Meteorological Institute (Belgium), the leading journal "Climatic Change ", established by Stephen Schneider).In 2019 he became member of a think tank of climate experts that was established in synergy with the climate strikes of the Belgian Youth For Climate, in which secondary school students left classes to demonstrate in favour of measures against climate change.Throughout 2019 he appeared as an assiduous supporter of the young activists.