Manfred Horvat1, Peng Gong2. 1. Manfred Horvat is an honorary professor at Vienna University of Technology, Austria, and adjunct professor at NTNU Norwegian University of Science and Technology, Norway. manfred.horvat@gmx.net. 2. Peng Gong is a professor at and chair of the Department of Earth System Science and dean of the School of Science at Tsinghua University in Beijing, China. penggong@mail.tsinghua.edu.cn.