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