Arthur Cracknell graduated in Physics from Cambridge University in 1961 and received his PhD in electronic band structure of metals from Oxford University in 1964. He worked as a lecturer in Physics at the Universities of Singapore and Essex before moving to Dundee University where he rose to become the Carnegie Professor of Physics. In Dundee he established a pioneering group in remote sensing with many graduate students (MSc and PhD). He and his collaborators have published over 300 research papers. With several different co-authors he has published 30 books on solid state physics and various aspects of remote sensing applications, several with Taylor & Francis/CRC, including of course the first edition of "Observing Global Climate Change." He is now an emeritus professor and continues to pursue his scientific interests. Costas Varotsos graduated in Physics from National and Kapodistrian University of Athens in 1980 and received his PhD in Atmospheric Physics from University of Thessaloniki in 1984. He teaches since 1989 Atmospheric and Environmental Physics and Chemistry, which are also the main topics of his research interests (e.g., Remote Sensing, Climate Dynamics, Atmospheric Physics & Chemistry, Environmental Change, Non-linear Processes). He has established four international research Laboratories in the Department of Environmental Physics of NKUA. He has published 14 monographs with Springer and more than 300 research papers in refereed journals and contributed with specific chapters to 6 edited books in the fields of Remote Sensing, Atmospheric Physics & Chemistry, and Environmental Change.