Shebeshe Assefa developed his master thesis at the Weizmann Institute of Science in Israel. He did his thesis work as an internship.Shebeshe describes this experience in his own words:

"This is to share with you my thesis research internship experience in my MEDFOR last semester. I had a very interesting and fruitful research internship time in Weizmann Institute of Science (WIS), Israel. The internship was realized through a bilateral cooperation between University of Lisbon (MEDFOR program coordinator), WIS (host institution), the Jewish National Fund (internship grant provider) and University of Valladolid (my 2nd year enrolling University). 

WIS is one of the world’s leading multidisciplinary basic research institutions. I joined Professor Dan Yakir’s lab, which is an Ecophysiology research group at the Department of Earth & Planetary Sciences. Their research focus on Biosphere-atmosphere interactions in arid and semiarid environmental conditions. The research work of the Ecophysiology tem includes ‘laboratory experiments at the leaf scale and soil patch; field work in a permanent research site in semi-arid forest and a dynamic mobile lab that combines field and lab work in different locations; and modeling at the ecosystem and global scales’ ( This link shows overviews of the very fantastic Yatir Forest research experiment site and the innovative and unique dynamic mobile lab of Professor Dan Yakir.

With a research idea initiated by Dr. Yakir Presiler (my main supervisor) I worked on the topic ‘How does precipitation pattern affect annual tree growth? A multi-year data analysis case study of semi-arid Yatir Forest, Israel’. Most of my work was based on the available climate, eddy covariance and tree ring data from Yatire Forest research site (

This internship was an amazing opportunity for me to learn and share with a  group of world leading experts in their field of study and to work with a group of brilliant, motivated, very friendly and helpful research teams. 

I am greatly thankful for all the lovely team members of the Ecophysiology team in WIS. Special Thanks to Dr. Yakir Preisler, my main supervisor who guided me brilliantly in all rounded aspects. Also, I would like to thank my co Supervisors Prof. Dan Yakir and Prof. Felipe Bravo. It will not be realized without the initiation of the collaboration by Mr. Asaf Karavani (JNF) and Dr. Catarina Tavares (MEDFOR coordinator), I kindly thank both of you for your unreserved help throughout my research internship stay.

I hope the project will continue and I would like to recommend and encourage my fellow MEDFOR student to use this interesting opportunity. You will find it a perfect opportunity to learn in a fantastic research institution."

From left to right: With Prof. Dan Yakir; with Dr Yakir Preisler at Yatir Forest and Yatir Forest Field Experiment Databases.