Diurnal Variation of Downslope Winds in Owens Valley during the Sierra Rotor Experiment

Jiang, Qingfang; Doyle, James D.
October 2008
Monthly Weather Review;Oct2008, Vol. 136 Issue 10, p3760
Academic Journal
The impact of diurnal forcing on a downslope wind event that occurred in Owens Valley in California during the Sierra Rotors Project (SRP) in the spring of 2004 has been examined based on observational analysis and diagnosis of numerical simulations. The observations indicate that while the upstream flow was characterized by persistent westerlies at and above the mountaintop level the cross-valley winds in Owens Valley exhibited strong diurnal variation. The numerical simulations using the Coupled Ocean–Atmosphere Mesoscale Prediction System (COAMPS) capture many of the observed salient features and indicate that the in-valley flow evolved among three states during a diurnal cycle. Before sunrise, moderate downslope winds were confined to the western slope of Owens Valley (shallow penetration state). Surface heating after sunrise weakened the downslope winds and mountain waves and eventually led to the decoupling of the well-mixed valley air from the westerlies aloft around local noon (decoupled state). The westerlies plunged into the valley in the afternoon and propagated across the valley floor (in-valley westerly state). After sunset, the westerlies within the valley retreated toward the western slope, where the downslope winds persisted throughout the night.


Related Articles

  • Aliasing of the semidiurnal cycle in the depiction of global atmospheric circulation. Tsing-Chang Chen; Schubert, Siegfried // Bulletin of the American Meteorological Society;Jan2000, Vol. 81 Issue 1, p95 

    Shows that the depiction of the semidiurnal signal inherent in the climatology of the atmospheric general circulation based on twice daily data leads to errors in the climatology. Portrayal of atmospheric general circulation by streamfunction and velocity potential function; Importance of...

  • Seasonality and Interannual Variability of the Westerly Jet in the Tibetan Plateau Region. Schiemann, Reinhard; Lüthi, Daniel; Schär, Christoph // Journal of Climate;Jun2009, Vol. 22 Issue 11, p2940 

    In this study, 40-yr ECMWF Re-Analysis (ERA-40) data are used for the description of the seasonal cycle and the interannual variability of the westerly jet in the Tibetan Plateau region. To complement results based on the analysis of monthly mean horizontal wind speeds, an occurrence-based jet...

  • The hourly gale record from Valentia Observatory, SW Ireland 1874-2008 and some observations on extreme wave heights in the NE Atlantic. Hickey, Kieran R. // Climatic Change;Jun2011, Vol. 106 Issue 3, p483 

    The sustained hourly gale record from Valentia Observatory, SW Ireland over the time period from 1874-2006 shows very significant variations including high values in the 1920s, 1940s, 1960s and 1980s but a decline since then down to the lowest recorded levels at present. Most gales occur in...

  • One Hundred and One Years of Netherlands' Windstorms.  // CO2 Science;5/ 8/2013, Vol. 16 Issue 19, p5 

    The article reports on a study conducted in the Netherlands which investigated the validity of the assumption that extreme weather events tend to become more frequent or more intense or both because of rising global temperature based on data on windstorms over a period of 101 years.

  • Determining the Boundary and Probability of Surface Urban Heat Island Footprint Based on a Logistic Model. Qiao, Zhi; Wu, Chen; Zhao, Dongqi; Xu, Xinliang; Yang, Jilin; Feng, Li; Sun, Zongyao; Liu, Luo // Remote Sensing;Jun2019, Vol. 11 Issue 11, p1368 

    Studies of the spatial extent of surface urban heat island (SUHI or UHISurf) effects require precise determination of the footprint (FP) boundary. Currently available methods overestimate or underestimate the SUHI FP boundary, and can even alter its morphology, due to theoretical limitations on...

  • Future wind and wave climate projections in the Indian Ocean based on a super-high-resolution MRI-AGCM3.2S model projection. Kamranzad, Bahareh; Mori, Nobuhito // Climate Dynamics;Aug2019, Vol. 53 Issue 3/4, p2391 

    In this study, the impact of climate change on wind and wave characteristics has been assessed using super-high-resolution MRI-AGCM3.2S wind data and numerical modeling over the Indian Ocean. Wave characteristics were generated in two 25-year periods covering historical and future projections...

  • Testing and analysis of the toe-nailed connection in the residential roof-to-wall system. Cheng, Jim // Forest Products Journal;Apr2004, Vol. 54 Issue 4, p58 

    This study focused on the toe-nailed connection between the roof structural member (rafter or truss) and wall (top plate), which is one of the critical links in the load path of a residential structure. More than 300 mechanical tests on toe-nailed connections with respect to spruce-pine-fir,...

  • European wind variability over 140 yr. Bett, P. E.; Thornton, H. E.; Clark, R. T. // Advances in Science & Research;2013, Vol. 10, p51 

    The article focuses on a study conducted to analyze the variability of wind speeds across Europe over the past 140 years. The recent Twentieth Century Reanalysis data set has been used in the study. According to the study, the variability between decades is large and no strong long-term trends...

  • Parametric Representation of the Primary Hurricane Vortex. Part II: A New Family of Sectionally Continuous Profiles. Willoughby, H. E.; Darling, R. W. R.; Rahn, M. E. // Monthly Weather Review;Apr2006, Vol. 134 Issue 4, p1102 

    For applications such as windstorm underwriting or storm-surge forecasting, hurricane wind profiles are often approximated by continuous functions that are zero at the vortex center, increase to a maximum in the eyewall, and then decrease asymptotically to zero far from the center. Comparisons...


Read the Article

Courtesy of

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics