EARTH SYSTEM SCIENCE FOR SUSTAINABILITY: HUMAN POPULATION IN MODELS AND POLICY

Understanding how the world works is the basic objective of Earth System Science (ESS); recommending solutions and policy to solve problems of the human colony in the Earth system is the stated or implied goal. Much basic and applied research is supported on the need to address problems related to geological or geophysical processes (e.g., flood, earthquake and landslide hazards), availability of resources (water, soil, coastal access and fisheries), and production of pollutants (global environmental change). Often in such research, human population is recognized as a component of hazard, resource or environmental impact models, but usually only as a given parameter, which is then removed from further consideration as a potential solution to the problem. For example, in an international program to reduce natural hazards, increased losses were recognized with increasing population –but no further action on population was suggested. As we build the bridge between the physical-chemical-biological model (Bretherton Diagram) and the human science (political-economic-social) model (Social Process Diagram) it will be essential to incorporate population and human impact as factors in potential solutions. Some reasons for omission include: 1) not appropriate for selected research team, 2) problem that can’t be addressed, 3) religious or political taboo, 4) others are working on it, and 5) not a problem. Many Earth system problems could be minimized or eliminated with fewer humans locally or globally. For sustainability over the next several hundred years we need ESS models (and model-based policies) that include changes in numbers (increases and decreases) and locations of humans and their impact in the system.