Polishing the Plume A New Visualization of Multi-Model Ensemble Forecasts Developed to Advance...

Polishing the Plume

A New Visualization of Multi-Model Ensemble

Forecasts Developed to Advance Climate

Prediction Research and Communication

Jennifer M. AdamsCenter for Ocean-Land-Atmosphere Studies

George Mason University

Google Image Search Results for “ENSO Plume”

The Whisk Brooms

Climate Diagnostics and Prediction Workshop, 2013

“Developing a More Reliable and Usable ENSO Prediction Plume”

by Tony Barnston, Mike Tippett, Huug van den Dool, and David Unger

An Early Failure

A Better Failure

The Wedding Cake

The Current Favorite

What Makes This Plume Shine?

• Histograms! Left-aligned for easy interpretation Colorized for quick readability Thin underline shows full range of values

• Less ink, more information• Clear identification of individual models • Individual and multi-model ensemble

means• The grey area between obs and forecasts

Histograms on TV

How To Draw Histograms With GrADS

• Sorting data and drawing histograms have not been implemented (yet).

• All the coding is done in the scripting language: Define the index in a dimension environment with E and T varying Parse results from ‘set gxout print’ output and populate a script variable Loop over data values, fill histogram bins, collect statistics Set up the X-Y space in the graphic with an invisible time series plot Use ‘q gr2xy’ and ‘draw recf’ to draw the histogram bars Scaling: Maximum mode value spans 90% of width between time steps,

so that no histogram overlaps the base of the subsequent histogram

The Plume for July 2015(Click HERE to see Most Recent)

Individual Model Plumes Initialized July

2015

Another Look at Individual Model Plumes(Click HERE to see in a browser)

Plume Evolution

Click to See Animation

Other Applications for the Plume

• Extended Indian Monsoon Rainfall (EIMR)

• Indian Ocean Dipole (IOD)• Point forecasts of daily maximum

temperature• Atmospheric teleconnection indices

Extended Indian Monsoon Rainfall Index(Precipitation Averaged over 70°E–110°E, 10°N–30°N, in mm/day)

Indian Ocean Dipole Index (Difference between area-averaged SST anomalies in the western and eastern Indian

Ocean)

Daily Min/Max Temperatures(Click HERE to See Latest)

Daily Max Temperature Forecast Plume(Click HERE to See Latest)

00z run

12z run

Next Target: The Cone of Uncertainty

Cones on TV

The HurriCone

Adopt the New Plume!

• The embedded histograms Declutter the plume Add useful information Improve readability

• Elegant distillation of ensemble information

• Useful for many weather and climate indicators