Julie E. Kiang
Julie E. Kiang, Deputy Regional Director
Science and Products
Filter Total Items: 31
Topological and canonical kriging for design flood prediction in ungauged catchments: an improvement over a traditional regional regression approach?
In the United States, estimation of flood frequency quantiles at ungauged locations has been largely based on regional regression techniques that relate measurable catchment descriptors to flood quantiles. More recently, spatial interpolation techniques of point data have been shown to be effective for predicting streamflow statistics (i.e., flood flows and low-flow indices) in ungauged catchments
Authors
Stacey A. Archfield, Alessio Pugliese, Attilio Castellarin, Jon O. Skøien, Julie E. Kiang
Calculating weighted estimates of peak streamflow statistics
According to the Federal guidelines for flood-frequency estimation, the uncertainty of peak streamflow statistics, such as the 1-percent annual exceedance probability (AEP) flow at a streamgage, can be reduced by combining the at-site estimate with the regional regression estimate to obtain a weighted estimate of the flow statistic. The procedure assumes the estimates are independent, which is rea
Authors
Timothy A. Cohn, Charles Berenbrock, Julie E. Kiang, Robert R. Mason,
Estimating discharge measurement uncertainty using the interpolated variance estimator
Methods for quantifying the uncertainty in discharge measurements typically identify various sources of uncertainty and then estimate the uncertainty from each of these sources by applying the results of empirical or laboratory studies. If actual measurement conditions are not consistent with those encountered in the empirical or laboratory studies, these methods may give poor estimates of dischar
Authors
T. Cohn, J. Kiang, R. Mason
Causes of systematic over- or underestimation of low streamflows by use of index-streamgage approaches in the United States
Low-flow characteristics can be estimated by multiple linear regressions or the index-streamgage approach. The latter transfers streamflow information from a hydrologically similar, continuously gaged basin ('index streamgage') to one with a very limited streamflow record, but often results in biased estimates. The application of the index-streamgage approach can be generalized into three steps: (
Authors
K. Eng, J.E. Kiang, Y.-Y. Chen, D.M. Carlisle, G.E. Granato
Climate Change and Water Resources Management: A Federal Perspective
Many challenges, including climate change, face the Nation's water managers. The Intergovernmental Panel on Climate Change (IPCC) has provided estimates of how climate may change, but more understanding of the processes driving the changes, the sequences of the changes, and the manifestation of these global changes at different scales could be beneficial. Since the changes will likely affect funda
Authors
Levi D. Brekke, Julie E. Kiang, J. Rolf Olsen, Roger S. Pulwarty, David A. Raff, D. Phil Turnipseed, Robert S. Webb, Kathleen D. White
Quantifying uncertainty in discharge measurements: A new approach
The accuracy of discharge measurements using velocity meters and the velocity-area method is typically assessed based on empirical studies that may not correspond to conditions encountered in practice. In this paper, a statistical approach for assessing uncertainty based on interpolated variance estimation (IVE) is introduced. The IVE method quantifies all sources of random uncertainty in the meas
Authors
J.E. Kiang, T.A. Cohn, R.R. Mason
Water loss in the Potomac River basin during droughts
The water loss phenomena in the Washington DC metropoliton area's (WMA) Potomac River water supply basin during droughts was analyzed. Gage errors, permitted withdrawals, evaporation, and transpiration by trees along the river were investigated to account for loss. The Interstate Commission on the Potomac River Basin (ICPRB) calculated potential gage error and examined permits to determine permitt
Authors
E.R. Hagen, J.E. Kiang, J.J.A. Dillow
Science and Products
Filter Total Items: 31
Topological and canonical kriging for design flood prediction in ungauged catchments: an improvement over a traditional regional regression approach?
In the United States, estimation of flood frequency quantiles at ungauged locations has been largely based on regional regression techniques that relate measurable catchment descriptors to flood quantiles. More recently, spatial interpolation techniques of point data have been shown to be effective for predicting streamflow statistics (i.e., flood flows and low-flow indices) in ungauged catchments
Authors
Stacey A. Archfield, Alessio Pugliese, Attilio Castellarin, Jon O. Skøien, Julie E. Kiang
Calculating weighted estimates of peak streamflow statistics
According to the Federal guidelines for flood-frequency estimation, the uncertainty of peak streamflow statistics, such as the 1-percent annual exceedance probability (AEP) flow at a streamgage, can be reduced by combining the at-site estimate with the regional regression estimate to obtain a weighted estimate of the flow statistic. The procedure assumes the estimates are independent, which is rea
Authors
Timothy A. Cohn, Charles Berenbrock, Julie E. Kiang, Robert R. Mason,
Estimating discharge measurement uncertainty using the interpolated variance estimator
Methods for quantifying the uncertainty in discharge measurements typically identify various sources of uncertainty and then estimate the uncertainty from each of these sources by applying the results of empirical or laboratory studies. If actual measurement conditions are not consistent with those encountered in the empirical or laboratory studies, these methods may give poor estimates of dischar
Authors
T. Cohn, J. Kiang, R. Mason
Causes of systematic over- or underestimation of low streamflows by use of index-streamgage approaches in the United States
Low-flow characteristics can be estimated by multiple linear regressions or the index-streamgage approach. The latter transfers streamflow information from a hydrologically similar, continuously gaged basin ('index streamgage') to one with a very limited streamflow record, but often results in biased estimates. The application of the index-streamgage approach can be generalized into three steps: (
Authors
K. Eng, J.E. Kiang, Y.-Y. Chen, D.M. Carlisle, G.E. Granato
Climate Change and Water Resources Management: A Federal Perspective
Many challenges, including climate change, face the Nation's water managers. The Intergovernmental Panel on Climate Change (IPCC) has provided estimates of how climate may change, but more understanding of the processes driving the changes, the sequences of the changes, and the manifestation of these global changes at different scales could be beneficial. Since the changes will likely affect funda
Authors
Levi D. Brekke, Julie E. Kiang, J. Rolf Olsen, Roger S. Pulwarty, David A. Raff, D. Phil Turnipseed, Robert S. Webb, Kathleen D. White
Quantifying uncertainty in discharge measurements: A new approach
The accuracy of discharge measurements using velocity meters and the velocity-area method is typically assessed based on empirical studies that may not correspond to conditions encountered in practice. In this paper, a statistical approach for assessing uncertainty based on interpolated variance estimation (IVE) is introduced. The IVE method quantifies all sources of random uncertainty in the meas
Authors
J.E. Kiang, T.A. Cohn, R.R. Mason
Water loss in the Potomac River basin during droughts
The water loss phenomena in the Washington DC metropoliton area's (WMA) Potomac River water supply basin during droughts was analyzed. Gage errors, permitted withdrawals, evaporation, and transpiration by trees along the river were investigated to account for loss. The Interstate Commission on the Potomac River Basin (ICPRB) calculated potential gage error and examined permits to determine permitt
Authors
E.R. Hagen, J.E. Kiang, J.J.A. Dillow