Understanding the effects of climatic variability is important to development of water resources, mitigation of flood hazards, and interpretation of geomorphic surfaces. Climatic variability, which is characterized by temporal changes in variability of seasonal climate that spans decades or centuries, may be more important to water-resources evaluations than changes in mean climatic conditions. Changes in variability of climate has a large effect on the probability of occurrence of extreme events, such as floods or droughts. Understanding of climatic variability and its effect on the landscape is of paramount importance for estimation of flood frequency, sediment transport rates, and long-term watershed and channel changes. The objectives [...]
Summary
Understanding the effects of climatic variability is important to development of water resources, mitigation of flood hazards, and interpretation of geomorphic surfaces. Climatic variability, which is characterized by temporal changes in variability of seasonal climate that spans decades or centuries, may be more important to water-resources evaluations than changes in mean climatic conditions. Changes in variability of climate has a large effect on the probability of occurrence of extreme events, such as floods or droughts. Understanding of climatic variability and its effect on the landscape is of paramount importance for estimation of flood frequency, sediment transport rates, and long-term watershed and channel changes. The objectives of this project are to define historic climatic variability in the western United States over the past century, to identify specific time periods of statistically stationary precipitation, discharge, flood frequency, and sediment transport, to assess the net effects of climatic variability on watershed conditions and fluvial systems, and to determine the extent that historic changes reflect Holocene climatic fluctuations. See Changes in Riparian Vegetation in Arizona for examples of how repeat photography has provided an invaluable record of changes in the riverine environment. Also see Mojave Ghost Town for repeat photography documentation of vegetation recovery in Mojave Desert areas that were settled in the late 19th and early 20th century and later abandoned.