Flooding on California's Russian River: Role of atmospheric rivers

2006 ◽  
Vol 33 (13) ◽  
Author(s):  
F. Martin Ralph ◽  
Paul J. Neiman ◽  
Gary A. Wick ◽  
Seth I. Gutman ◽  
Michael D. Dettinger ◽  
...  
Keyword(s):  
Atmospheric Rivers ◽  
Russian River

Observed Impacts of Duration and Seasonality of Atmospheric-River Landfalls on Soil Moisture and Runoff in Coastal Northern California

2013 ◽  
Vol 14 (2) ◽  
pp. 443-459 ◽  
Author(s):  
F. M. Ralph ◽  
T. Coleman ◽  
P. J. Neiman ◽  
R. J. Zamora ◽  
M. D. Dettinger
Keyword(s):  
Soil Moisture ◽  
Water Vapor Transport ◽  
Total Water ◽  
Atmospheric Rivers ◽  
Runoff Volume ◽  
Total Runoff ◽  
Russian River ◽  
Moisture Conditions ◽  
Peak Streamflow

Abstract This study is motivated by diverse needs for better forecasts of extreme precipitation and floods. It is enabled by unique hourly observations collected over six years near California’s Russian River and by recent advances in the science of atmospheric rivers (ARs). This study fills key gaps limiting the prediction of ARs and, especially, their impacts by quantifying the duration of AR conditions and the role of duration in modulating hydrometeorological impacts. Precursor soil moisture conditions and their relationship to streamflow are also shown. On the basis of 91 well-observed events during 2004–10, the study shows that the passage of ARs over a coastal site lasted 20 h on average and that 12% of the AR events exceeded 30 h. Differences in storm-total water vapor transport directed up the mountain slope contribute 74% of the variance in storm-total rainfall across the events and 61% of the variance in storm-total runoff volume. ARs with double the composite mean duration produced nearly 6 times greater peak streamflow and more than 7 times the storm-total runoff volume. When precursor soil moisture was less than 20%, even heavy rainfall did not lead to significant streamflow. Predicting which AR events are likely to produce extreme impacts on precipitation and runoff requires accurate prediction of AR duration at landfall and observations of precursor soil moisture conditions.

scholarly journals The role of atmospheric rivers in anomalous snow accumulation in East Antarctica

2014 ◽  
Vol 41 (17) ◽  
pp. 6199-6206 ◽  
Author(s):  
Irina V. Gorodetskaya ◽  
Maria Tsukernik ◽  
Kim Claes ◽  
Martin F. Ralph ◽  
William D. Neff ◽  
...  
Keyword(s):  
Snow Accumulation ◽  
East Antarctica ◽  
Atmospheric Rivers

Extreme Surface Winds During Landfalling Atmospheric Rivers: The Modulating Role of Near-Surface Stability

2021 ◽  
Author(s):  
Terence J. Pagano ◽  
Duane E. Waliser ◽  
Bin Guan ◽  
Hengchun Ye ◽  
F. Martin Ralph ◽  
...  
Keyword(s):  
Water Vapor ◽  
Static Stability ◽  
Vapor Transport ◽  
Water Vapor Transport ◽  
Surface Winds ◽  
Near Surface ◽  
Extreme Surface ◽  
Atmospheric Rivers ◽  
Explained Variance

AbstractAtmospheric rivers (ARs) are long and narrow regions of strong horizontal water vapor transport. Upon landfall, ARs are typically associated with heavy precipitation and strong surface winds. A quantitative understanding of the atmospheric conditions that favor extreme surface winds during ARs has implications for anticipating and managing various impacts associated with these potentially hazardous events. Here, a global AR database (1999–2014) with relevant information from MERRA-2 reanalysis, QuikSCAT and AIRS satellite observations are used to better understand and quantify the role of near-surface static stability in modulating surface winds during landfalling ARs. The temperature difference between the surface and 1 km MSL (ΔT; used here as a proxy for near-surface static stability), and integrated water vapor transport (IVT) are analyzed to quantify their relationships to surface winds using bivariate linear regression. In four regions where AR landfalls are common, the MERRA-2-based results indicate that IVT accounts for 22-38% of the variance in surface wind speed. Combining ΔT with IVT increases the explained variance to 36-52%. Substitution of QuikSCAT surface winds and AIRS ΔT in place of the MERRA-2 data largely preserves this relationship (e.g., 44% compared to 52% explained variance for USA West Coast). Use of an alternate static stability measure–the bulk Richardson number–yields a similar explained variance (47%). Lastly, AR cases within the top and bottom 25% of near-surface static stability indicate that extreme surface winds (gale or higher) are more likely to occur in unstable conditions (5.3%/14.7% during weak/strong IVT) than in stable conditions (0.58%/6.15%).

Tracking the storage and dissipation of atmospheric river storm water in the Russian River watershed using GPS elastic displacements

2021 ◽  
Author(s):  
Ellen Knappe ◽  
Adrian Borsa ◽  
Hilary Martens ◽  
Donald Argus ◽  
Zachary Hoylman ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Water Storage ◽  
Heavy Precipitation ◽  
Storm Water ◽  
Hydrologic Models ◽  
Effective Technique ◽  
Atmospheric Rivers ◽  
River Watershed ◽  
Russian River ◽  
Flooding Events

<p>GPS is emerging as an effective technique to estimate changes in total water storage at Earth's surface.  In California's mountains, GPS indicates that more subsurface storage is lost during drought and gained during years of heavy precipitation than predicted by hydrology models [Argus et al. 2017].  Atmospheric rivers provide a majority of the annual precipitation in coastal environments across North America. The Russian River watershed is often affected by these large storms, which can produce extensive flooding events. In this study, we estimate changes in water storage for the 2017 water year (October 2016 – September 2017), a historically wet year in California, in which more than 20 atmospheric rivers impacted the Russian River watershed. Using GPS displacements, we quantify the water gained during higher intensity atmospheric rivers. We further resolve the time it takes for the storm water to dissipate: that is, we distinguish between water that runs off into rivers and water that is stored in the ground as soil moisture. Finally, we investigate the empirical relationships between GPS displacement and precipitation, evapotranspiration, and soil moisture estimates with the aim of improving constraints to hydrologic models.</p>

Modulation of Atmospheric Rivers by Mesoscale Frontal Waves and Latent Heating: Comparison of Two U.S. West Coast Events

2021 ◽  
Author(s):  
Allison C. Michaelis ◽  
Andrew C. Martin ◽  
Meredith A. Fish ◽  
Chad W. Hecht ◽  
F. Martin Ralph
Keyword(s):  
Moisture Transport ◽  
Initial Conditions ◽  
Vapor Transport ◽  
Latent Heating ◽  
Dynamic Precipitation ◽  
Atmospheric Rivers ◽  
River Watershed ◽  
Diabatic Processes ◽  
Low Altitude ◽  
Russian River

AbstractA complex and underexplored relationship exists between atmospheric rivers (ARs) and mesoscale frontal waves (MFWs). The present study further explores and quantifies the importance of diabatic processes to MFW development and the AR-MFW interaction by simulating two ARs impacting Northern California’s flood-vulnerable Russian River watershed using the Model for Prediction Across Scales-Atmosphere (MPAS-A) with and without the effects of latent heating. Despite the storms’ contrasting characteristics, diabatic processes within the system were critical to the development of MFWs, the timing and magnitude of integrated vapor transport (IVT), and precipitation impacts over the Russian River watershed in both cases. Low-altitude circulations and lower-tropospheric moisture content in and around the MFWs are considerably reduced without latent heating, contributing to a decrease in moisture transport, moisture convergence, and IVT. Differences in IVT are not consistently dynamic (i.e., wind-driven) or thermodynamic (i.e., moisture-driven), but instead vary by case and by time throughout each event. For one event, AR conditions over the watershed persisted for 6 h less and the peak IVT occurred 6 h earlier and was reduced by ~17%; weaker orographic and dynamic precipitation forcings reduced precipitation totals by ~64%. Similarly, turning off latent heating shortened the second event by 24 h and reduced precipitation totals by ~49%; the maximum IVT over the watershed was weakened by ~42% and delayed by 18 h. Thus, sufficient representation of diabatic processes, and by inference, water vapor initial conditions, is critical for resolving MFWs, their feedbacks on AR evolution, and associated precipitation forecasts on watershed scales.

scholarly journals The 2010/2011 snow season in California's Sierra Nevada: Role of atmospheric rivers and modes of large-scale variability

2013 ◽  
Vol 49 (10) ◽  
pp. 6731-6743 ◽  
Author(s):  
Bin Guan ◽  
Noah P. Molotch ◽  
Duane E. Waliser ◽  
Eric J. Fetzer ◽  
Paul J. Neiman
Keyword(s):  
Sierra Nevada ◽  
Large Scale ◽  
Atmospheric Rivers ◽  
Snow Season

scholarly journals The Hydrometeorological Observation Network in California’s Russian River Watershed: Development, Characteristics, and Key Findings from 1997 to 2019

2020 ◽  
Vol 101 (10) ◽  
pp. E1781-E1800 ◽  
Author(s):  
Edwin Sumargo ◽  
Anna M. Wilson ◽  
F. Martin Ralph ◽  
Rachel Weihs ◽  
Allen White ◽  
...  
Keyword(s):  
The United States ◽  
Hybrid Network ◽  
Federal State ◽  
Atmospheric Rivers ◽  
Atmospheric River ◽  
Weather Events ◽  
Observation Network ◽  
State And Local Government ◽  
State And Local ◽  
Russian River

AbstractThe Russian River Hydrometeorological Observing Network (RHONET) is a unique suite of high-resolution in situ and remote sensing observations deployed over 20 years to address both scientific and operational gaps in understanding, monitoring, and predicting weather and water extremes on the United States’ West Coast. It was created over many years by diverse organizations ranging from universities to federal, state, and local government agencies and utilities. Today, RHONET is a hybrid network with diverse observation sets aimed at advancing scientific understanding of physical processes driving extreme precipitation and runoff in the region. Its development is described, including the specific goals that led to a series of network enhancements, as well as the key characteristics of its sensors. The hydroclimatology of the Russian River area is described, including an overview of the hydrologic extremes and variability driving the scientific and operational needs in the region, from atmospheric river behavior and orographic precipitation processes to hydrologic conditions related to water supply and flooding. A case study of Lake Mendocino storage response to a landfalling atmospheric river in 2018 is presented to demonstrate the network’s performance and hydrologic applications during high-impact weather events. Finally, a synopsis of key scientific findings and applications enabled by the network is provided, from the first documentation of the role of landfalling atmospheric rivers in flooding, to the occurrence of shallow nonbrightband rain, to the buffering influence of extremely dry soils in autumn, and to the development of forecast-informed reservoir operations for Lake Mendocino.

scholarly journals Rivers in the sky, flooding on the ground: the role of atmospheric rivers in inland flooding in central Europe

2020 ◽  
Vol 24 (11) ◽  
pp. 5125-5147
Author(s):  
Monica Ionita ◽  
Viorica Nagavciuc ◽  
Bin Guan
Keyword(s):  
North Atlantic ◽  
Heavy Rainfall ◽  
Large Scale ◽  
Pressure Center ◽  
Atmospheric Rivers ◽  
Extreme Flooding ◽  
Large Scale Atmospheric Circulation ◽  
Rhine Catchment ◽  
Lower Rhine

Abstract. The role of large-scale atmospheric circulation and atmospheric rivers (ARs) in producing extreme flooding and heavy rainfall events in the lower part of the Rhine catchment area is examined in this study. Analysis of the largest 10 floods in the lower Rhine, between 1817 and 2015, shows that all these extreme flood peaks have been preceded up to 7 d in advance by intense moisture transport from the tropical North Atlantic basin in the form of narrow bands also known as atmospheric rivers. Most of the ARs associated with these flood events are embedded in the trailing fronts of the extratropical cyclones. The typical large-scale atmospheric circulation leading to heavy rainfall and flooding in the lower Rhine is characterized by a low pressure center south of Greenland, which migrates toward Europe, and a stable high pressure center over the northern part of Africa and the southern part of Europe and projects on the positive phase of the North Atlantic Oscillation. On the days preceding the flood peaks, lower (upper) level convergence (divergence) is observed over the analyzed region, which indicates strong vertical motions and heavy rainfall. Vertically integrated water vapor transport (IVT) exceeds 600 kg m−1 s−1 for the largest floods, marking these as very strong ARs. The results presented in this study offer new insights regarding the importance of moisture transport as a driver of extreme flooding in the lower part of the Rhine catchment area, and we show, for the first time, that ARs are a useful tool for the identification of potentially damaging floods in inland Europe.

Sign in / Sign up

Export Citation Format

Share Document