1 / 12

Verification of Probabilistic Forecast

RA VI Clips Workshop. Verification of Probabilistic Forecast. J.P. Céron – Direction de la Climatologie S. Mason - IRI. The Exercise. identify the forecasts of El Niño, Neutral, and La Niña years. L. E E E E E.

alec-travis
Download Presentation

Verification of Probabilistic Forecast

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. RA VI Clips Workshop Verification of Probabilistic Forecast J.P. Céron – Direction de la Climatologie S. Mason - IRI

  2. The Exercise • identify the forecasts of El Niño, Neutral, and La Niña years L E E E E E E L

  3. The Exercise • identify the forecasts of El Niño, Neutral, and La Niña years

  4. The Exercise • calculate forecast probabilities for El Niño, neutral, and La Niña events 0 % 80 % 20 % 100 % 0 % 0 % 20 % 60 % 20 %

  5. The Exercise • calculate forecast probabilities for El Niño, neutral, and La Niña events

  6. The Exercise • calculate forecast biases 20 % - 33 % The frequency of La Niña forecasts is 18 / (18*5) = 0,20 The observed frequency of La Niña events is 6 / 18 = 0,33

  7. The Exercise • calculate forecast biases

  8. The Exercise • calculate the Hit Rate and False Alarme Rate 1,00 1,00 0,83 0,25 0,83 0,00 0,50 0,00 0,50 0,00 0,17 0,00

  9. The Exercise • calculate the Hit Rate and False Alarme Rate

  10. The Exercise • ROC diagram

  11. The Exercise • ROC diagram

  12. The Exercise • Brier skill scores • Differences between the ROC areas and Brier skill scores • The ROC areas indicate more optimistic estimates of forecast skill, most notably for the neutral conditions. • The Brier skill score indicates negative skill for forecasts of neutral conditions. The Brier skill scores for this category are weak because of the large forecast bias, but the ROC ignores the bias.

More Related