CSU Presentation

S

Analysis of Convectively Coupled Equatorial Kelvin Waves in a GCM with

a Modified Entrainment Profile

Raymond RuizDept. of Physical and Mathematical Sciences at North Carolina State University, Raleigh, NC

Walter Hannah, & Dr. Eric MaloneyDept. of Atmospheric Sciences, Colorado State University, Fort Collins, CO

About Me

http://upload.wikimedia.org/wikipedia/commons/c/c4/Hurricane_Georges_(Puerto_Rico).PNG

Born in Puerto Rico

Hurricane George

Senior at North Carolina State University

Tropical Meteorology, Severe Weather, and SNOW

Convectively Coupled Kelvin Waves

Eastward propagating waves C= √gH,

H is equivalent Depth Major weather producer in the tropics Not well represented in Global Climate Models

Entrainment

Entrainment Turbulent flow captures

non-turbulent flow Mixing more

environmental air, diluting, less potent

Allows for representation of Shallow Convection

http://www.cmmap.org/images/learn/clouds/entrainment.jpg

Model and Parameterizations

Observational- NOAA interpolated OLR data used from 1980-2011

NCAR Community Atmosphere Model 5 (CAM5).

Control- Entrainment known as the Relaxed Arakawa and Schubert (RAS) Total Precip. Mm/day

Experiment- Entrainment in model is being increased(λ) Total Precip. Mm/day

Methods

Energy as a function of frequency and wavenumber

Kelvin wave filtering process

All season variance plots in order to obtain area of greatest signal

Wave regression with multiple variables, horizontal structure, latitude vs. longitude

Wave lagged regression for cross section overview, time vs. height

Wheeler and Kiladis et al.

Function of frequency vs. Zonal wave number

Theoretical curves vs. Power

Tells us propagation speeds and wave cycle

Control Experiment

Observation

All Season Varience

Experiment

Observation

Control

Theoretical Kelvin Wave

Regression Technique

Observation -OLR

Control -Precip

Experiment -Precip

Observation

Control

Experiment

Heating Specific Humidity

Zonal Wind Temperatur

e

Observation

Control

Experiment

Summary

Slower propagation speeds Linear, coherent propagation signal More pronounced vertical structure General improvements, causes for improvements

require further research.

Thanks for listening!!! Good Luck Leah!