Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.
-
Upload
britney-anthony -
Category
Documents
-
view
222 -
download
0
Transcript of Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.
![Page 1: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/1.jpg)
Winds
Yin (2000) JAM
Annual mean winds
![Page 2: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/2.jpg)
Annual Cycle in Wind
Yin (2000) JAM
Annual cycle amplitude
![Page 3: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/3.jpg)
Peak Wind Season
Yin (2000) JAM
Time of peak wind
![Page 4: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/4.jpg)
Diurnal Mountain Winds
• Diurnal mountain winds develop from terrain of all scales
• Circulations arise as a result of differential heating between the ground in regions of complex terrain and free atmosphere at the same elevation– During day, higher terrain is an elevated heat source
– During night, higher terrain is an elevated heat sink
![Page 5: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/5.jpg)
Sacramento Valley
Zaremba and Carroll (1999)JAM
![Page 6: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/6.jpg)
Grand Canyon
Whiteman et al. 1999JAM
![Page 7: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/7.jpg)
Kali Gandaki Valley
Egger et al. (2000)MWR
![Page 8: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/8.jpg)
Mountain wind systems
• Slope winds- driven by horizontal temperature contrasts between air over valley sidewalls and air over center of valley
• Along-valley winds- driven by contrasts along valley’s axis and nearby plain
• Cross-valley winds- driven by contrasts between opposing sidewalls
• Mountain-plain winds- driven by contrasts between plateau and nearby plains
![Page 9: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/9.jpg)
Mountain Wind Systems
Whiteman (2000)
![Page 10: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/10.jpg)
Terminology
• Katabatic wind: cold flow of air travelling downward or down a slope
• Anabatic wind: air current or wind rising up a slope
![Page 11: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/11.jpg)
Slope Winds
Whiteman (2000)
![Page 12: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/12.jpg)
Slope flows• Closed circulation driven by horizontal temperature contrasts between
the air over the slope and the air at the same level over the center of the valley
• Speeds- 1-5 m/s with maximum a few meters above the ground
• Increase in speed as length of slope increases (Antarctica 14-30 m/s)
• Strongest downslope at sunset; strongest upslope in midmorning
• Depth of downslope ~5% of drop in elevation from top
• Upslope flows increase in depth as move upslope
• Stronger the stability, shallower the slope flows
• Downslope flows converge into gullies; upslope flows converge over higher ground between gullies
![Page 13: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/13.jpg)
Slope flows
Whiteman (2000)
ColdWarmWarmCold
Du’/dt = g’ ( en- )/=g’ (T-Ten)/Ten= g’ (-en)/en
g
g’
![Page 14: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/14.jpg)
Basin Circulations
• Enclosed terrain features develop slope flows but weak along-valley circulations
• Enhanced heating during the daytime and cooling at night as a result of absence of along-valley advection of cool/warm air
• Light winds
![Page 15: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/15.jpg)
Night flows
Whiteman (2000)
![Page 16: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/16.jpg)
Thermal belt
Whiteman (2000)
![Page 17: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/17.jpg)
Slope Flows in Peter Sink Basin
• Record cold temperature in Utah: Peter Sinks –57C
• Clements (2001) conducted field program in remote basin in northern Utah to study slope flows
• Field program held 8-12 Sept. 1999
![Page 18: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/18.jpg)
Peter Sinks
![Page 19: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/19.jpg)
North Peter Sink
Vegetation inversion
![Page 20: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/20.jpg)
Peter Sinks Terrain
![Page 21: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/21.jpg)
Perimeter
![Page 22: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/22.jpg)
Instrumentation Layout
![Page 23: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/23.jpg)
Net Radiation and Sonic Anemometer
![Page 24: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/24.jpg)
Surface Energy Budget- Idealized
Whiteman (2000)
![Page 25: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/25.jpg)
Surface Energy Budget- Peter Sinks
Strong net heating during day; surface losing energy during night
![Page 26: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/26.jpg)
Surface Temperature Variation
Coldest air in the basin- warm air on slopes
![Page 27: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/27.jpg)
Tethersonde Operations
![Page 28: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/28.jpg)
VerticalStructurein basin
dw/dt = -g/en(den/dz)dz
Stability increases as evening progresses
Winds weaken with time
![Page 29: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/29.jpg)
Temperature Mast on Slope
![Page 30: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/30.jpg)
Temperature Variation on Slope
Strong inversion below 2 m; isothermal above
![Page 31: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/31.jpg)
Vertical Structure on Slope
Light drainage winds on slopes; nonexistent most of the time
![Page 32: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/32.jpg)
Potential Temperature Profiles Along Slope
Observations from Peter Sinks do not agree with classical model of relatively deep cold air on slopes draining down into basin
![Page 33: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/33.jpg)
Morning Transition
![Page 34: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/34.jpg)
Morning Transition
dw/dt = -g/en(en/z)dz
Stability decreases as morning progresses
Winds strengthen with time
![Page 35: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/35.jpg)
Katabatic flow
Poulos et al. 2000MWR
![Page 36: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/36.jpg)
Simulation of Katabatic Wind
Poulos et al. (2000)MWR
![Page 37: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/37.jpg)
Antarctica Katabatic Winds
Bromwich (1989) BAMS
![Page 38: Winds Yin (2000) JAM Annual mean winds. Annual Cycle in Wind Yin (2000) JAM Annual cycle amplitude.](https://reader036.fdocuments.net/reader036/viewer/2022062423/5697bfc41a28abf838ca5c01/html5/thumbnails/38.jpg)
Divergence Salt Lake Valley: Interaction of Slope and Valley Winds
Convergence
Divergence
October 2000. M. Splitt