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, slope winds respond to temperature differences between the air heated or cooled by a slope and undisturbed air at the same level ( Prandtl 1952 ; Schumann 1990 ; Haiden 2003 ). At a larger scale, valley winds are generated by thermal imbalances between the core of the valley volume and the atmosphere above a nearby plain. A comprehensive description of the different phases composing the daily cycle of thermally driven flows in a mountain valley, with emphasis on the interaction between slope and
, slope winds respond to temperature differences between the air heated or cooled by a slope and undisturbed air at the same level ( Prandtl 1952 ; Schumann 1990 ; Haiden 2003 ). At a larger scale, valley winds are generated by thermal imbalances between the core of the valley volume and the atmosphere above a nearby plain. A comprehensive description of the different phases composing the daily cycle of thermally driven flows in a mountain valley, with emphasis on the interaction between slope and
1. Introduction Owens Valley is a narrow valley in eastern California, approximately north–south oriented and bounded by the highest portion of the Sierra Nevada (high sierra) to the west and by the White–Inyo Range to the east. Within such a valley, one expects different types of terrain-induced circulations ( Whiteman 2000 ) to occur. Dynamically driven winds [e.g., topographically channeled flow and intense downslope winds related to mountain waves] are the result of the local modification
1. Introduction Owens Valley is a narrow valley in eastern California, approximately north–south oriented and bounded by the highest portion of the Sierra Nevada (high sierra) to the west and by the White–Inyo Range to the east. Within such a valley, one expects different types of terrain-induced circulations ( Whiteman 2000 ) to occur. Dynamically driven winds [e.g., topographically channeled flow and intense downslope winds related to mountain waves] are the result of the local modification
patterns over Da-Tun Mountain, during the influence of wintertime northeasterly flow. One rainfall pattern is characterized by two local rainfall maxima near the mountain crests of Mt. Zhu-Zi and Mt. Huang-Zui, which are closely related to upslope lifting, as confirmed by an upslope model ( Cheng and Yu 2019 ). The other observed rainfall pattern features a local precipitation maximum inside Huang-Xi Valley. This rainfall distribution cannot be simply explained by upslope lifting and tends to occur as
patterns over Da-Tun Mountain, during the influence of wintertime northeasterly flow. One rainfall pattern is characterized by two local rainfall maxima near the mountain crests of Mt. Zhu-Zi and Mt. Huang-Zui, which are closely related to upslope lifting, as confirmed by an upslope model ( Cheng and Yu 2019 ). The other observed rainfall pattern features a local precipitation maximum inside Huang-Xi Valley. This rainfall distribution cannot be simply explained by upslope lifting and tends to occur as
1. Introduction On fair-weather days, transport and mixing of heat, moisture, and other constituents over mountainous terrain is strongly influenced by the thermally forced mountain circulations, the slope, and valley winds. These mountain flows also play a key role in the formation of clouds and convection initiation ( Banta 1990 ). Also, the quantification of the associated exchange processes is important for many applications such as air-quality studies, numerical weather prediction, and
1. Introduction On fair-weather days, transport and mixing of heat, moisture, and other constituents over mountainous terrain is strongly influenced by the thermally forced mountain circulations, the slope, and valley winds. These mountain flows also play a key role in the formation of clouds and convection initiation ( Banta 1990 ). Also, the quantification of the associated exchange processes is important for many applications such as air-quality studies, numerical weather prediction, and
within a valley near Vancouver, Canada by altering low-level stability. Later work by Conrick et al. (2018) over the Olympic Mountains of Washington State showed that flow blocking and terrain interactions were associated with down-valley flow in some cases, but the large-scale pressure difference played a significant role in others. Alongside the implications for airflow and temperature, precipitation may also be affected by down-valley flow and its coincident conditions. James and Houze (2005
within a valley near Vancouver, Canada by altering low-level stability. Later work by Conrick et al. (2018) over the Olympic Mountains of Washington State showed that flow blocking and terrain interactions were associated with down-valley flow in some cases, but the large-scale pressure difference played a significant role in others. Alongside the implications for airflow and temperature, precipitation may also be affected by down-valley flow and its coincident conditions. James and Houze (2005
( Fig. 1b ). The ZZ and HZ ridge arms flank funnel-shaped, lower-terrain regions upstream of the HX valley. Such concave-like mountain ranges are commonly seen in other geographical locations, such as the Cascades in North America, the Alps, and the southeastern Australia, and often have a higher potential to produce severe precipitation ( Frei and Schär 1998 ; Jiang 2006 ; Watson and Lane 2012 , 2014 ). Interactions among orographically modified flows occurring over different portions of the
( Fig. 1b ). The ZZ and HZ ridge arms flank funnel-shaped, lower-terrain regions upstream of the HX valley. Such concave-like mountain ranges are commonly seen in other geographical locations, such as the Cascades in North America, the Alps, and the southeastern Australia, and often have a higher potential to produce severe precipitation ( Frei and Schär 1998 ; Jiang 2006 ; Watson and Lane 2012 , 2014 ). Interactions among orographically modified flows occurring over different portions of the
1. Introduction A combination of real and virtual topography, as opposed to the real or actual topography alone, will be shown to describe the essentials of stratified flow over mountain ranges and leeside valleys or plains when a layer capped by a strong density step exists above the topography. This cap acts as virtual topography for the stratified flow aloft and will control its response. Vosper (2004) and Jiang (2014) explored the role of such a cap in theoretical and idealized
1. Introduction A combination of real and virtual topography, as opposed to the real or actual topography alone, will be shown to describe the essentials of stratified flow over mountain ranges and leeside valleys or plains when a layer capped by a strong density step exists above the topography. This cap acts as virtual topography for the stratified flow aloft and will control its response. Vosper (2004) and Jiang (2014) explored the role of such a cap in theoretical and idealized
OCTOBER 1990 STEVEN K. SAKIYAMA 1015Drainage Flow Characteristics and Inversion Breakup in Two Alberta Mountain Valleys STEVEN K. SAKIYAMAAlberta Department of the Environment, Edmonton, Alberta, Canada(Manuscript received 14 September 1989, in final form 9 April 1990)ABSTRACT Wind and temperature profiles and corresponding acoustic sounder data collected in September 1982 arepresented for
OCTOBER 1990 STEVEN K. SAKIYAMA 1015Drainage Flow Characteristics and Inversion Breakup in Two Alberta Mountain Valleys STEVEN K. SAKIYAMAAlberta Department of the Environment, Edmonton, Alberta, Canada(Manuscript received 14 September 1989, in final form 9 April 1990)ABSTRACT Wind and temperature profiles and corresponding acoustic sounder data collected in September 1982 arepresented for
, and climate modeling (e.g., Rotach et al. 2004 , 2008 ; Gohm et al. 2009 ). But they also directly influence the characteristics of local weather and climate such as near-surface temperatures, wind speeds, cloudiness, and precipitation (e.g., Egger et al. 2000 ). Despite the importance of the diurnal mountain winds, there is still some uncertainty regarding the influence of the valley surroundings and the larger-scale plain-to-mountain flow on the dynamics of the valley wind. The major cause
, and climate modeling (e.g., Rotach et al. 2004 , 2008 ; Gohm et al. 2009 ). But they also directly influence the characteristics of local weather and climate such as near-surface temperatures, wind speeds, cloudiness, and precipitation (e.g., Egger et al. 2000 ). Despite the importance of the diurnal mountain winds, there is still some uncertainty regarding the influence of the valley surroundings and the larger-scale plain-to-mountain flow on the dynamics of the valley wind. The major cause
contributing to the CAP and mountain flow exiting the HBEF valley into the Pemigewasset River valley. The air in the upper part of the CAP likely originated from the reservoir of free atmospheric air above the CAP that has little temperature change at night. Free tropospheric and/or residual layer air continually feeds into the katabatic flow on the upper slopes because of continuity, is cooled along the slopes, and then flows across the upper part of the CAP. The bottom of the CAP likely maintained a
contributing to the CAP and mountain flow exiting the HBEF valley into the Pemigewasset River valley. The air in the upper part of the CAP likely originated from the reservoir of free atmospheric air above the CAP that has little temperature change at night. Free tropospheric and/or residual layer air continually feeds into the katabatic flow on the upper slopes because of continuity, is cooled along the slopes, and then flows across the upper part of the CAP. The bottom of the CAP likely maintained a
