Roy W. Spencer
- Ph.D., Meteorology, University of Wisconsin-Madison (1981). 
Abandoned oil and gas wells in Alberta are on the rise — but where many see a growing liability, Alberta’s...
Karlen is a retired professor in the department of Physical Geography and Quaternary Geology from Stockholm University.
According to the NRSP, Clark completed his graduate studies at the University of Waterloo and at the Université de Paris Sud (Orsay) in isotope hydrogeology and paleoclimatology. 
Clark is a professor in the Department of Earth Sciences at the University of Ottawa.