- Ph.D., Meteorology, Florida State University.
- M.Sc., Meteorology, Florida State University.
- M.Sc., Statistics, Pune University (India).
- B.Sc., Mathematics.
- B.Sc., Physics.
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.
Past professor of aeronautical engineering, and the past director of research at the Royal Netherlands Meteorological Institute. 
Hendrik (Henk) Tennekes is a retired researcher from the Netherlands known for his work in the fields of turbulence and multi-modal forecasting.