Professor Stephen Borrmann Institute for Atmospheric Physics Johannes-Gutenberg University Max Planck Institute for Chemistry – Mainz, Germany As recognized in science and increasingly in politics and business water will play the role of the “main fuel” for future conflicts. The former Secretary-General of the United Nations, Kofi Annan, referred to water as “the conflict material of the 21st century” already in 2003. Verstraete et al. (2009) summarize the importance of water: Global poverty defined in almost every way, is disproportionally concentrated in the arid, semiarid, and dry subhumid regions—the drylands- of the world, where people living in such areas are trapped in a downward spiral of environmental degradation and loss of well-being. Between 38% and 47% of the Earth’s land area consists of such “subhumid” regions, where currently about one-third of humanity lives. Desertification, or the spread of deserts, also continues almost unabated. On July 28, 2010, the United Nations included the right to clean water in the declaration of universal human rights. However, humanity is further away from balanced water supply than ever before. As estimated by the UN, around 2050 between 2 and 7 billion people are expected to be affected by water scarcity, and it is not surprising that nearly 300 potential crisis zones were identified, where military conflicts could arise over the availability of freshwater. This presentation first selectively discusses a few general facts about water availability from the confusing variety of different, sometimes conflicting sources of information. A brief discussion of the effects of climate change on the hydrological cycle will follow, which includes a highly simplified description of the main underlying meteorological and atmospheric-physical mechanisms. At this point considering the situation of the ice on Earth becomes important as the ice/snow cover is rapidly declining almost everywhere. The phenomenon directly affects the issue of sufficient water availability, because many of the most important river systems (e.g., in Asia, Europe, the US) are dependent on the ice reservoirs in our planet’s mountains. Since concern about this is growing rapidly, the issue of the global ice is also discussed at the end of this presentation. Date September 6, 2023 Time 11 AM PST Location MBARI7700 Sandholdt RoadMoss Landing, CA 95039 Seminar recording This seminar recording is only available for staff and can be found on the seminar archives page.