In 2013 , Stoltenberg served as a UN special envoy on climate change ( global warming ) .
Stoltenberg has chaired the UN High - Level Panel on System Wide Coherence and the High - Level Advisory Group on Climate Change Financing .
In 2013 , Stoltenberg served as a UN special envoy on climate change ( global warming ) , and he has chaired the UN High - Level Panel on System Wide Coherence and the High - Level Advisory Group on Climate Change Financing .