Notes

Outline

Cross Equatorial Systems  Northern and Southern Hemisphere Intrusions Mike Davison HPC International Desks

Slide 2

Characteristics of Northern Hemisphere Ridges and Troughs Ridge Warm Core Anticyclonic (negative/clockwise) relative vorticity increases with height High tropopause heights Trough Cold Core Cyclonic (Positive/     counterclockwise) relative vorticity increases with height Low tropopause heights

Northern Hemisphere Upper Ridge/Trough Pattern

Northern Hemisphere Ridge Winds and Temperature

Northern Hemisphere Ridge Winds and Potential Temperature

Northern Hemisphere Ridge Winds and Relative Vorticity

Northern Hemisphere Trough Winds and Temperature

Northern Hemisphere Trough Winds and Potential Temperature

Northern Hemisphere Trough Winds and Relative Vorticity

Characteristics of Southern Hemisphere Ridges and Troughs Ridge Warm Core Anticyclonic (Positive/     counterclockwise) relative vorticity increases with height High tropopause heights Trough Cold Core Cyclonic (negative/clockwise) relative vorticity increases with height Low tropopause heights

Southern Hemisphere Upper Trough/Ridge Pattern

Southern Hemisphere Ridge Winds and Temperature

Southern Hemisphere Ridge Winds and Potential Temperature

Southern Hemisphere Ridge Winds and Relative Vorticity

Southern Hemisphere Trough Winds and Temperature

Southern Hemisphere Trough Winds and Potential Temperature

Southern Hemisphere Trough Winds and Relative Vorticity

What Happens When a Southern Hemisphere System Crosses the Equator? Northern Hemisphere Southern Hemisphere

Does it behaves like a Nrn Hemisphere Ridge or a Srn Hemisphere Trough?

Case Study 31 Oct 2001

Evaluation of Upper Circulation over the Tropical Atlantic

Vertical Cross Section of Temperature (C) and Winds

Vertical Cross Section of Relative Vorticity and Winds

Vertical Cross Section of Potential Temperature (K), Winds, and Relative Vorticity

Vertical Cross Section of  Potential Temperature (K) and Winds

250 hPa Winds and Divergence Objective Analysis

250 hPa Winds

250 hPa Winds and Divergence Objective Analysis

Verification

IR Loop

WV Loop