Ancient floods, modern hazards: Principles and applications of paleoflood hydrology

✍ Scribed by Eric C. Carson

• Publisher: John Wiley and Sons
• Year: 2003
• Tongue: English
• Weight: 46 KB
• Volume: 18
• Category: Article
• ISSN: 0883-6353
• DOI: 10.1002/gea.10061

✦ Synopsis

Paleoflood hydrology, in its emergence and maturation as a science over the past three decades, has incorporated diverse tools such as dendrochronology, cosmogenic geochronology, and remote sensing into traditional methods of stratigraphic analysis and numerical modeling. As a result, a multitude of methodologies and techniques are available for reconstructing the occurrences of ancient floods. The recent growth of paleoflood hydrology has provided the impetus for P. Kyle House, Robert H. Webb, Victor R. Baker, and Daniel R. Levish to compile this series of papers detailing current methods and applications of the discipline, distilled from presentations at the Second International Paleoflood Conference in Prescott, Arizona, in September 1999. The conference was "dedicated to presenting the stateof-the-art in paleoflood hydrology," so both the presentations at the conference and the papers presented in this volume represent a wide, inclusive range of the foremost research and scientists in the field. Thus, Ancient Floods, Modern Hazards: Principles and Applications of Paleoflood Hydrology is a thorough introduction to the field for all manner of Quaternary geoscientists, as well as a worthy reference for hydrologists and geomorphologists.

As the title intimates, the monograph is divided into two main parts: "Principles and Methods" and "Applications." These sections are book-ended by introductory "Background" papers and a concluding "Perspective" paper. In the two introductory chapters, Baker et al. and Redmond et al. firmly establish the importance of paleoflood hydrology in relation to both academia and society. Baker et al. provide a brief history of the discipline, introduce the primary concepts and methods, and finally argue for the role of paleoflood hydrology research in societal issues. Redmond et al. identify the factors influencing the climate-hydrologic system over various timescales as a bridge between historic flood analysis and interpretation of paleoflood studies.

The section on Principles and Methods comprise nine papers. The first two papers in this section present the utility of remote sensing data (low-altitude airborne geophysical surveys in the Pickup et al. paper and Landsat TM data in the Mayer and Pearthree paper) for delineating floodplain topographic elements in reconstructing paleo-and modern flood magnitudes in arid environments. The next two papers deal with field determination of paleoflood stage and frequency. Yanosky and Jarrett focus specifically on the principles of dendrochronologic methods in paleoflood hydrology, while Jarrett and England provide a more general review of paleoflood stage indicators. The latter paper is particularly interesting in that the authors used paleoflood stage indicators to model the discharges of modern floods, which they compared to independent measurements of peak discharges from the same floods to evaluate the reliability of the stage indicators. The following two papers deal with the techniques for modeling discharges of paleo-and modern floods. Webb and Jarrett detail the principle one-dimensional discharge estimation methods that rely on flood stage indicators chronicled in the two preceding papers. This paper provides a particularly concise review of the mathematic and hydrologic assumptions that underlie the commonly used slope-area, step-backwater, and critical-depth methods. Denlinger et al. introduce the methods associated with two-dimensional discharge estimation. In their discussion of the 1993 Verde River flood, they argue that the additional data collection necessary for a two-dimensional model is justified by the more realistic and detailed characterization of flood conditions provided by the two-dimensional code than a one-dimensional model. The final three papers in this section cover several disparate loose ends in methods of paleoflood hydrology. Carling et al. move from flood discharge estimation to the hydraulics of boulder entrainment in bedrock channels. Blainey et al. discuss the