Entries by Mikael Mulugeta

Generalizing a nonlinear geophysical flood theory to medium‐sized river networks

The central hypothesis of a nonlinear geophysical flood theory postulates that, given space‐time rainfall intensity for a rainfall‐runoff event, solutions of coupled mass and momentum conservation differential equations governing runoff generation and transport in a self‐similar river network produce spatial scaling, or a power law, relation between peak discharge and drainage area in the limit […]

Examining Regional Flood Frequency in the U.S. Midwest

The focus of this study is to evaluate: (1) “mixtures” of flood peak distributions, (2) upper tail and scaling properties of the flood peak distributions, and (3) presence of temporal nonstationarities in the flood peak records. Villarini, G., J.A. Smith, M.L. Baeck, and W.F. Krajewski. “Examining Regional Flood Frequency in the U.S. Midwest,” Journal of the American […]

Inundation Mapping Initiatives of the Iowa Flood Center: Statewide Coverage and Detailed Urban Flooding Analysis

The State of Iowa, located in the Midwestern United States, has experienced an increased frequency of large floods in recent decades. After extreme flooding in the summer of 2008, the Iowa Flood Center (IFC) was established for advanced research and education specifically related to floods. Gilles, D.G., N.C. Young, J.A. Piotrowski, H.S. Schroeder, and Y.J. Chang. “Inundation Mapping Initiatives of […]

A framework for flood risk assessment under nonstationary conditions or in the absence of historic data

We present a diagnostic framework to assess changes in flood risk across multiple scales in a river network, under nonstationary conditions or in the absence of historical hydro-meteorological data. The framework combines calibration-free hydrological and hydraulic models with urban development information to demonstrate altered flood risk. Cunha, L.K., W.F. Krajewski, and R. Mantilla. “A Framework for Flood Risk […]

An Analytical Formula for Potential Water Vapor in an Atmosphere of Constant Lapse Rate

Accurate calculation of precipitable water vapor (PWV) in the atmosphere has always been a matter of importance for meteorologists. Potential water vapor (POWV) or maximum precipitable water vapor can be an appropriate base for estimation of probable maximum precipitation (PMP) in an area, leading to probable maximum flood (PMF) and flash flood management systems. Varmaghani, […]

Detecting inhomogeneities in the Twentieth Century Reanalysis over the central United States

We use three statistical methods (Pettitt and Bai‐Perron tests and segmented regression) to detect abrupt shifts in multiple hydrometeorological variable mean and uncertainty fields over the central United States. For surface air temperature and precipitation, we use the Climate Research Unit (CRU) time series data set for comparison. We find that for warm‐season months, there […]

Impact of radar‐rainfall error structure on estimated flood magnitude across scales: An investigation based on a parsimonious distributed hydrological model

The goal of this study is to diagnose the manner in which radar‐rainfall input affects peak flow simulation uncertainties across scales. We used the distributed physically based hydrological model CUENCAS with parameters that are estimated from available data and without fitting the model output to discharge observations. Cunha, L.K., P.V. Mandapaka, W.F. Krajewski, R. Mantilla, and A.A. Bradley. “Impact […]

On the temporal clustering of US floods and its relationship to climate teleconnection patterns

This article examines whether the temporal clustering of flood events can be explained in terms of climate variability or time‐varying land‐surface state variables. Villarini, G., J.A. Smith, R. Vitolo, and D.B. Stephenson. “On the Temporal Clustering of U.S. Floods and Its Relationship to Climate Teleconnection Patterns,” International Journal of Climatology, 33, 3, pp. 629–640, 2013.

Projections of heavy rainfall over the central United States based on CMIP5 models

Several studies based on observational records found increasing trends over the central United States. Recently, Villarini et al. (2013) found a large increase in the number of rainfall days exceeding the 95th percentile of the rainfall distribution over the Upper Mississippi River Basin, and a much weaker signal in the Lower Mississippi River Basin. Villarini, G., […]