Dr. Maurits van den Berg (Maurits.vandenBerg@pbl.nl), the Netherlands Environmental Assessment Agency, Bilthoven, The Netherlands.
Prof. Awad Osman Abusuwar (Abusuwar@yahoo.com), Faculty of Meteorology, Environment and Arid Land Agriculture, Kind Abdulaziz University, Jeddah, Saudi Arabia.
Prof. Tageldin Elshaikh Musa Hago (tageIdeenhajo@yahoo.com), Department of Agronomy, Faculty of Agriculture, University of Khartoum.
Dr. Mahmoud Fadel Mula Ahmed (mfahmed@yahoo.com), Department of Agronomy, Faculty of Agriculture, University of Khartoum.
