Swedish 16-year-old Thunberg is a climate activist, who drew global attention to her cause by going on a school strike to demand political action on climate change, and sparking similar student strikes throughout the world.
Stern is an expert on the climate problem in economics, and Hulot is France's former environmental minister who, frustrated with his government's environmental policies, resigned from his position last year.
The new Honorary Doctors will now become part of a strong tradition of openness of mind, creativity and freedom of thought.
Previous laureates include Muhamad Yunus (2010), Bertrand Piccard and André Borschberg (2012), Daniel Cohen (2015), Edwy Plenel (2016), Albert Jacquard (1996), Claudie Haigneré (2008), Gisèle Halimi (1998) and Jean Ziegler (2004).
The Brussels Times