Regional Hydrologic Cycle

Research (1.7Mb)


The water cycle of the Euphrates-Tigris watershed: natural processes and human impacts.

Long term water resource planning is a challenge for many nations of the world. In predominantly dry nations, water resource scarcity may limit development and cause political tensions with neighboring states. These challenges often occur in the developing world where they are compounded by sparse in-situ climate and hydrologic data. This proposal focuses on the water cycle in the Euphrates-Tigris watershed. The watershed includes portions of Turkey, Syria, Iran, Iraq and Saudi Arabia. It includes large areas of arid and semi-arid lands, zones of intensive agriculture as well as high mountainous terrain. The objective of this proposal is to utilize sensors on the Terra and Aqua satelites (MODIS, ASTER, AIRS, AMSU, AMSR-E and HSB), along with in-situ data and various advanced modeling techniques, to characterize the water cycling within this watershed and its sensitivity to land use change and climatic variability.

In attempting to answer the general question: How sensitive is the hydrologic system in the Euphrates-Tigris catchment to local changes in land use/land cover and interannual climatic variability? several issues of particular interest will be addressed.

  • What is the relative importance of water vapor sources internal and external to the catchment in the production of precipitation within the catchment?
  • What is the role played by mountains in producing the precipitation that feeds the Tigris and Euphrates?
  • What changes in the rangeland vegetation are occurring and what impact do they have on the hydrologic system?
  • How do changes in irrigated agriculture influence the rest of the hydrologic system?
A final synthesis of answers to the above questions will provide a basis from which to address the general question of hydrologic system sensitivity.

Last update: 15 January 2004
This page is maintained by Jason Evans