the jet stream, high and low pressure systems and fronts
TRANSCRIPT
![Page 1: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/1.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
The Jet Stream, high and low pressure systemsand fronts; Understanding the weather
Joe LaCasceDept. of Geosciences
January 25, 2010
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 2: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/2.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Table of contents
1 Introduction
2 Basic dynamicsGeostrophic balanceHydrostatic balanceThermal wind balanceThe Jet Stream
3 Anatomy of a stormStorm formationFronts
4 Forecasts
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 3: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/3.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Hurricane
Figure: Hurricane Ivan, Sept. 2004
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 4: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/4.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Polar low
Figure: A polar low over the Barents Sea, 27 Feb., 1987
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 5: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/5.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Hurricane
Figure: Hurricane Katrina, Aug. 2005
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 6: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/6.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Flooding
Figure: Coastal flooding, England
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 7: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/7.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Snow
Figure: Chicago, 2009
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 8: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/8.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
8 Jan., 2010; www.yr.no
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 9: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/9.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
8 Jan., 2010; www.yr.no
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 10: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/10.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Geostrophic balanceHydrostatic balanceThermal wind balanceThe Jet Stream
Dynamics
Basic balances:
Geostrophic balance
Hydrostatic balance
Thermal wind balance
Phenomena:
Pressure systems
Jet Stream
Fronts and precipitation
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 11: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/11.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Geostrophic balanceHydrostatic balanceThermal wind balanceThe Jet Stream
Rotation
veltotal = velperson + velrotation
so:velperson = veltotal − velrotation
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 12: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/12.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Geostrophic balanceHydrostatic balanceThermal wind balanceThe Jet Stream
Deflection
Figure: Deflection to the right in the Northern Hemisphere
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 13: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/13.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Geostrophic balanceHydrostatic balanceThermal wind balanceThe Jet Stream
Low pressure without rotation
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 14: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/14.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Geostrophic balanceHydrostatic balanceThermal wind balanceThe Jet Stream
Low pressure with rotation
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 15: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/15.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Geostrophic balanceHydrostatic balanceThermal wind balanceThe Jet Stream
High pressure with rotation
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 16: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/16.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Geostrophic balanceHydrostatic balanceThermal wind balanceThe Jet Stream
Geostrophic balance
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 17: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/17.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Geostrophic balanceHydrostatic balanceThermal wind balanceThe Jet Stream
Hurricane
Figure: Hurricane Ivan
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 18: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/18.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Geostrophic balanceHydrostatic balanceThermal wind balanceThe Jet Stream
Hydrostatic balance
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 19: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/19.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Geostrophic balanceHydrostatic balanceThermal wind balanceThe Jet Stream
Thermal wind
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 20: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/20.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Geostrophic balanceHydrostatic balanceThermal wind balanceThe Jet Stream
Jet stream
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 21: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/21.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Geostrophic balanceHydrostatic balanceThermal wind balanceThe Jet Stream
Jet stream
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 22: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/22.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Geostrophic balanceHydrostatic balanceThermal wind balanceThe Jet Stream
Jet stream
Figure: Wallace and Hobbs, 2006
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 23: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/23.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Geostrophic balanceHydrostatic balanceThermal wind balanceThe Jet Stream
Instability and turbulence
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 24: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/24.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Storm formationFronts
Jet stream
Figure: Wallace and Hobbs, 2006
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 25: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/25.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Storm formationFronts
Storm formation
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 26: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/26.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Storm formationFronts
Storm formation
Figure: Wallace and Hobbs, 2006
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 27: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/27.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Storm formationFronts
Fronts
Warm/cold fronts
Vertical motion
→ precipitation
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 28: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/28.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
Storm formationFronts
Squall
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 29: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/29.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
8 Jan., 2010; www.yr.no
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 30: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/30.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
8 Jan., 2010; UK Met Office
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 31: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/31.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
9 Jan., 2010; UK Met Office
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather
![Page 32: The Jet Stream, high and low pressure systems and fronts](https://reader033.vdocuments.site/reader033/viewer/2022061102/629d812ae8c009481d3295ba/html5/thumbnails/32.jpg)
IntroductionBasic dynamics
Anatomy of a stormForecasts
25 Jan., 2010; UK Met Office
Joe LaCasce Dept. of Geosciences The Jet Stream, high and low pressure systems and fronts; Understanding the weather