Tracking an Atmospheric River in a Warmer Climate: from Water Vapor to Economic Impacts

Abstract

Abstract. Atmospheric rivers (ARs) account for more than 75% of heavy precipitation events and nearly all of the extreme flooding events along the Olympic Mountains and western Cascade mountains of western Washington state. In a warmer climate, ARs in this region are projected to become more frequent and intense, primarily due to increases in atmospheric water vapor. However, it is unclear how the changes in water vapor transport will affect regional flooding and associated economic impacts. In this work, we present an integrated modeling system to quantify the atmospheric-hydrologic-hydraulic and economic responses of the climate system to future radiative forcings and c) different responses of the surface hydrologic system. In the warming scenario, AR integrated vapor transport increases, however, these changes do not translate into generalized increases 10 in precipitation throughout the basin. The changes in precipitation translate into spatially heterogeneous changes in sub-basin runoff and increased streamflow along the entire Chehalis main stem. Economic losses due to stock damages increased moderately, but losses in terms of business interruption were significant. Our integrated modeling tool provides communities in the Chehalis region with a range of possible future physical and economic impacts associated with AR flooding.

Evaluation of the moisture sources in two extreme landfalling atmospheric river events using an Eulerian WRF tracers tool

“…The first event developed over the Pacific Ocean and corresponds to the Great Coastal Gale of 2007 on the US Pacific West Coast, which resulted in an estimated USD 678 million in direct economic damages (Dominguez et al, 2017). The Atlantic event corresponds to an atmospheric river event in October 1987 that resulted in record winds of 100 km h −1 and daily precipitation of over 100 mm day −1 in Galicia (in the northwest of Spain) and Portugal.…”

“…1a-d). Locally known as the "Great Coastal Gale of 2007", this event primarily impacted the western state of Washington, and the associated flooding resulted in approximately USD 680 million direct losses from three severely impacted counties in the state (Avelino and Dall'erba, 2016;Dominguez et al, 2017) and 11 fatalities (NOAA, 2008). Formed from the remnants of the two typhoons Hagibis and Mitag, the event produced hurricane force winds (Crout et al, 2008).…”

Impact of Atmospheric Rivers on Surface Hydrological Processes in Western U.S. Watersheds

“…ARs are projected to be more frequent and intense in the future as warmer temperatures increase the moisture in the atmosphere (Gao et al, ; Lavers et al, , ; Warner et al, ). These changes in ARs may trigger more frequent and intense floods, which could cause significant socioeconomic impact (Dominguez et al, ; Lavers et al, ). However, an analysis of the overall hydrologic impacts of ARs is still missing.…”

Freezing Rain Events Related to Atmospheric Rivers and Associated Mechanisms for Western North America

“…The potential intensification of the AR‐related FR in the future climate as projected in this study implies a possible increase in the socio‐economic impact of ARs. The recent study by Dominguez et al () used an RCM to simulate a historical AR event and track it from its initial development stage to the final economic impact based on an integrated modeling tool. This methodology can provide useful information for the mitigation of AR related economic losses within the context of a changing climate.…”

“…Atmospheric rivers (ARs) are important midlatitude synoptic systems featured by a river‐like moist belt with intense water vapor transport in the lower troposphere (Zhu & Newell, ). ARs have been considered to be responsible for extreme weather events that threaten the west coast regions of North America (e.g., Ralph et al, ; Guan et al, ; Ralph & Dettinger, ; Neiman et al, ; Guan et al, , ; Oakley et al, ; Konrad & Dettinger, ; Waliser & Guan, ) and can result in major socioeconomic losses (Dominguez et al, ). This has been recently highlighted by the strong AR that made landfall in Coastal California in February 2017, causing severe flooding and landslides across California (Rosen, ), leaving five people dead and losses of 1.5 billion U.S. dollars.…”