Hydroclimate of the Western United States Based on Observations and Regional Climate Simulation of 1981–2000. Part II: Mesoscale ENSO Anomalies

AbstractA high-resolution (4 km) regional climate simulation conducted with the Weather Research and Forecast (WRF) model is used to investigate potential impacts of global warming on skiing conditions in the interior western United States (IWUS). Recent past and near-future climate conditions are compared. The past climate period is from November 1981 to October 2011. The future climate applies to a 30-year period centered on 2050. A pseudo global warming approach is used, with the driver re-analysis dataset perturbed by the CMIP5 ensemble mean model guidance. Using the 30-year retrospective simulation, a vertical adjustment technique is used to determine meteorological parameters in the complex terrain where ski areas are located. For snow water equivalent (SWE), Snow Telemetry sites close to ski areas are used to validate the technique and apply a correction to SWE in ski areas. The vulnerability to climate change is assessed for 71 ski areas in the IWUS considering SWE, artificially produced snow, temperature, and rain. 20 of the ski areas will tend to have fewer than 100 days per season with sufficient natural and artificial snow for skiing. These ski areas are located at either low elevations or low latitudes making these areas the most vulnerable to climate change. Throughout the snow season, natural SWE decreases significantly at the low elevations and low latitudes. At higher elevations changes in SWE are predicted to not be significant in the mid-season. In mid-February, SWE decreases by 11.8% at the top elevations of ski areas while it decreases by 25.8% at the base elevations.

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Evaluating Seasonal Orographic Precipitation in the Interior Western United States Using Gauge Data, Gridded Precipitation Estimates, and a Regional Climate Simulation

Journal of Hydrometeorology ◽

10.1175/jhm-d-17-0056.1 ◽

2017 ◽

Vol 18 (9) ◽

pp. 2541-2558 ◽

Cited By ~ 10

Author(s):

Xiaoqin Jing ◽

Bart Geerts ◽

Yonggang Wang ◽

Changhai Liu

Keyword(s):

United States ◽

Complex Terrain ◽

Model Simulation ◽

Regional Climate ◽

Wrf Model ◽

Stage Iv ◽

Western United States ◽

Climate Simulation ◽

Orographic Precipitation ◽

Precipitation Estimates

Abstract There are several high-resolution (1–12 km) gridded precipitation datasets covering the interior western United States. This study cross validates seasonal orographic precipitation estimates from the Snowpack Telemetry (SNOTEL) network; the national hourly multisensor precipitation analysis Stage IV dataset (NCEP IV); four gauge-driven gridded datasets; and a 10-yr, 4-km, convection-permitting Weather Research and Forecasting (WRF) Model simulation. The NCEP IV dataset, which uses the NEXRAD network and precipitation gauges, is challenged in this region because of blockage and lack of low-level radar coverage in complex terrain. The gauge-driven gridded datasets, which statistically interpolate gauge measurements over complex terrain to better estimate orographic precipitation, are challenged by the highly heterogeneous, weather-dependent nature of precipitation in complex terrain at scales finer than can be resolved by the gauge network, such as the SNOTEL network. Gauge-driven gridded precipitation estimates disagree in areas where SNOTEL gauges are sparse, especially at higher elevations. The WRF simulation captures wintertime orographic precipitation distribution and amount well, and biases over specific mountain ranges are identical to those in an independent WRF simulation, suggesting that these biases are at least partly due to errors in the snowfall measurements or the gridding of these measurements. The substantial disagreement between WRF and the gridded datasets over some mountains may motivate reevaluation of some gauge records and installation of new SNOTEL gauges in regions marked by large discrepancies between modeled and gauge-driven precipitation estimates.

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Transient high-resolution regional climate simulation for Greece over the period 1960-2100: evaluation and future projections

Climate Research ◽

10.3354/cr01304 ◽

2015 ◽

Vol 64 (2) ◽

pp. 123-140 ◽

Cited By ~ 10

Author(s):

P Zanis ◽

E Katragkou ◽

C Ntogras ◽

G Marougianni ◽

A Tsikerdekis ◽

...

Keyword(s):

High Resolution ◽

Regional Climate ◽

Climate Simulation ◽

Regional Climate Simulation ◽

Future Projections

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Statistical-dynamical extrapolation of a nested regional climate simulation

Climate Research ◽

10.3354/cr019001 ◽

2001 ◽

Vol 19 ◽

pp. 1-13 ◽

Cited By ~ 5

Author(s):

U Busch ◽

D Heimann

Keyword(s):

Regional Climate ◽

Climate Simulation ◽

Regional Climate Simulation

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Cool season precipitation projections for California and the Western United States in NA-CORDEX models

Climate Dynamics ◽

10.1007/s00382-021-05632-z ◽

2021 ◽

Author(s):

Kelly Mahoney ◽

James D. Scott ◽

Michael Alexander ◽

Rachel McCrary ◽

Mimi Hughes ◽

...

Keyword(s):

United States ◽

Climate Models ◽

Snow Water Equivalent ◽

Regional Climate ◽

Regional Climate Models ◽

Western United States ◽

Monthly Precipitation ◽

Wet Season ◽

Cool Season ◽

Projected Change

AbstractUnderstanding future precipitation changes is critical for water supply and flood risk applications in the western United States. The North American COordinated Regional Downscaling EXperiment (NA-CORDEX) matrix of global and regional climate models at multiple resolutions (~ 50-km and 25-km grid spacings) is used to evaluate mean monthly precipitation, extreme daily precipitation, and snow water equivalent (SWE) over the western United States, with a sub-regional focus on California. Results indicate significant model spread in mean monthly precipitation in several key water-sensitive areas in both historical and future projections, but suggest model agreement on increasing daily extreme precipitation magnitudes, decreasing seasonal snowpack, and a shortening of the wet season in California in particular. While the beginning and end of the California cool season are projected to dry according to most models, the core of the cool season (December, January, February) shows an overall wetter projected change pattern. Daily cool-season precipitation extremes generally increase for most models, particularly in California in the mid-winter months. Finally, a marked projected decrease in future seasonal SWE is found across all models, accompanied by earlier dates of maximum seasonal SWE, and thus a shortening of the period of snow cover as well. Results are discussed in the context of how the diverse model membership and variable resolutions offered by the NA-CORDEX ensemble can be best leveraged by stakeholders faced with future water planning challenges.

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