water transport in jet stream winds
DESCRIPTION
Water Transport in Jet Stream Winds. Surface Water Hydrology Term Project Cédric DAVID. Overview. 1. Introduction 2. Data and Programming 3. Results 4. Conclusions. 1. Introduction. 1. Introduction. Upper level of the atmosphere. Wind. View from the North Pole. Jet Stream. - PowerPoint PPT PresentationTRANSCRIPT
Water Transport in Jet Stream Winds
Surface Water Hydrology Term Project
Cédric DAVID
Overview
• 1. Introduction
• 2. Data and Programming
• 3. Results
• 4. Conclusions
1. Introduction
1. Introduction
Wind
Jet Stream
View from the North Pole
Upper level of the atmosphere
1. Introduction
What happens?
• Upper air winds regulate air masses
• Their deflection by the Coriolis acceleration creates Jet Streams
1. Introduction
Wind
1. Introduction
Wind
Altitude: 13000m
Altitude: 10000m
1. Introduction
Jet Stream• Its position denotes
strongest SURFACE temperature contrast
• 100 – 300 km/h28 – 80 m/s
• Weaker in the summer (smaller T gradient)In the US
1. Introduction
Jet Streak
• 300 km/h
• Jet streaks are localized regions of very fast winds embedded within the jet stream.
2. Data and Programming
2. Data and Programming
IDV Software
Java-based software framework for analyzing and visualizing geoscience data
2. Data and Programming
• National Oceanic and Atmospheric Administration
• National Center for Environmental Prediction
• National Weather Service
North American
Regional Reanalysis
2. Data and Programming
NARR A Monthly
• Pressure
• Temperature
• Specific Humidity
• Wind Speed
• Dew Point Temperature
2. Data and Programming
• NARR.xml ( Too Long)
• NARR Homepage (Download .grb grid files)– FTP server– Choose the desired options (levels,
parameters and sub regions)
• Open them with (degrib, Climate Data Operator, finally IDV)
2. Data and Programming
Formulas in IDV
Jython programming language
Java version of Python
can work with VisAD objects directly (no loop on the grid necessary)
ws=sqrt(u2+v2)
2. Data and Programming
2. Data and Programming
3. Results
3. Results
Jet Streak
Cross section with filtered Jet Stream
Whole NARR Domain
Long Computation time
3. ResultsJuly
29 m/s isovolume
Just above the Great Lakes
3. Results12000m
July
3. ResultsJuly
3. ResultsDecember
29 m/s isovolume
Just above Florida
GOES SOUTH!
3. Results12000m
December
3. ResultsDecember
3. Results
Jython formulas– Select Jet Stream
– Specific Humidity Flow in Jet Stream
bavv
bac
vab
va
jet
2
28
28
vjetqvf
3. Results
Jython formulas– Total Pressure p
(not in the NARR)
– Density of vapor v
– Mass of water
v
d
d
q
ep
T
Te
622.0
)3.237
27.17exp(611
avv
aa
q
TR
p
dVdm v
4. Conclusions
• Limitation of Jython:– only basic mathematical computation– cannot access single cell (easily)
• IDV– Good graphic interface– Calculations and formulas
• Power of IDV and NARR– Visual aspect of the results– Able to show known phenomena
Questions?
• http://www.physicalgeography.net/fundamentals/7q.html
• http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/cyc/upa/jet.rxml