now been observed. Gleick also served as co-lead author of the Water Sector Report of the first National Climate Assessment, published in 2000. The National Climate Assessment (NCA) is a United States government interagency ongoing effort on climate change science conducted under the auspices of the Global Change Research Act of 1990. The NCA is a major product of the U.S. Global Change Research Program (USGCRP) which coordinates a team of experts and receives input from a Federal Advisory Committee. Environment and security As a post-doctoral fellow in 1987 and 1988 at the University of California, Berkeley, Gleick published some of the earliest work addressing the risks of environmental factors for national and international security, including both climate change and water resources. Up until this time, most academic work on international security was linked to realpolitik and superpower relationships between the United States and the Soviet Union. In the 1980s, tensions between the superpowers shifted after the collapse of the Soviet Union. Simultaneously, there was growing concern about a far broader range of threats to peace, including environmental threats associated with the political implications of resource use or large-scale pollution. By the mid-1980s, this field of study was becoming known as "environmental security" and it is now widely acknowledged that environmental factors play both direct and indirect roles in both political disputes and violent conflicts. Prominent early researchers in the field include Norman Myers, Jessica Tuchman Mathews, Michael Renner, Richard Ullman, Arthur Westing, Michael Klare, Thomas Homer Dixon, and Geoffrey Dabelko. Gleick’s 1989 paper in the journal Climatic Change addressed how climate changes could affect regional and global tensions over global food production, access to strategic minerals in the Arctic, and freshwater resources. and his 1993 paper in the journal International Security focused on the threat of violence over water resources. He has continued to focus on these issues and created and maintains the Water Conflict Chronology, a comprehensive online database of violence associated with water resources, published by the Pacific Institute. This database goes back nearly 6,000 years, with over 1000 entries identifying where water resources or systems have been the trigger, target, or weapon of violence. This work has been recognized by military and intelligence community analysts and Gleick has briefed political military leaders and lectured at the U.S. Army War College and National War College in Washington D.C. The human right to water Gleick also did some