1 / 11

Outline

A Recent Abrupt Decline in the East African Long Rains Bradfield Lyon and David G. DeWitt Presented by: Tufa Dinku tufa@iri.columbia.edu International Research Institute for Climate and Society The Earth Institute at Columbia University. Outline. The Decline The Driver(?) Modeling experiment.

aulii
Download Presentation

Outline

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. A Recent Abrupt Decline in the East African Long RainsBradfield Lyon and David G. DeWittPresented by: Tufa Dinkutufa@iri.columbia.eduInternational Research Institute for Climate and SocietyThe Earth Institute at Columbia University

  2. Outline • The Decline • The Driver(?) • Modeling experiment

  3. Rainfall Decline: Regional CAMS_OPI (mm/day) anomaly for Mar-May 2011 CMAP Mar-May(1999-2010 average) anomaly (from 1979-2010 mean) Mar-May total RR , averaged over (10S-12N, 30-53E) Box..

  4. Apr-May PRCP (1998-2008) – (1979-1996) CMAP GPCP

  5. Rainfall Decline: Ethiopia

  6. Rainfall Decline: Ethiopia Annual Rainfall, country average from different number of stations

  7. Spatial Rainfall pattern Weights for leading mode(16.3% of VAR) of March-May precipitation obtained from EOF analysis of CAMS_OPI data for 1979-2011 Principal component time series for March-May leading mode

  8. What is the driver? March-May SST anomaly averaged from 1999-2011, expressed as a standardized departure from the 1971-2000 mean Loadings for the 2nd mode of March-May SST based on an EOF analysis for the period 1950-2011. Principal component time series (1950-2011)

  9. The Driver: East Africa April-May Rainfall Index and Tropical SST Correlation (1979-2010)

  10. Modeling

  11. Modeling Experiment • Multi-model ensemble mean (72 members) MAM RR anomaly (mm/day) from simulations using observed SSTs, averaged over1999-2009. • Ensemble mean (24 members) ECHAM5 precipitation anomaly (mm/day) from idealized runs forced with observed March-May SST anomalies averaged over 1999-2010 for the tropical Indian Ocean only. • As in b, but for model runs forced with SSTs only for the tropical Pacific. Top legend only for a); bottom legend for b and c.

More Related