[1] Beijing Normal Univ, State Key Lab Water Environm Simulat, Sch Environm, Beijing 100875, Peoples R China
[2] King Abdulaziz Univ, Fac Sci, NAAM Grp, Jeddah, Saudi Arabia
[3] Univ Maryland, Dept Geog Sci, College Pk, MD 20742 USA
[4] Univ East Anglia, Tyndall Ctr Climate Change Res, Norwich NR4 7TJ, Norfolk, England
[5] Univ East Anglia, Sch Int Dev, Norwich NR4 7TJ, Norfolk, England
[6] Quaid I Azam Univ, Dept Math, Islamabad 45320, Pakistan