# Presentation: 925266

## Seasonal Climate Diagnostics Consortium:

- Analysis of the NDJF 2002-03 climate
- forecasts and observations in NE U.S.
- (What the heck happened?)

- Tony Barnston, Arun Kumar,
- Lisa Goddard and Marty Hoerling
- CDPW, October 2003, Reno, Nevada

## ‘                ‘

- o

## Slide 3

## CDC’s multi-model AGCM-mimicking CCA:

- Forecast made Nov 2002 for DJF 2002/03

##                   DJF 2002-03 Surface Temperature                                                                                                               

-                   DJF 2002-03 Surface Temperature
-            Made November using predicted SST

- _______________________________________________________

## Canonical surface temperature El Nino response

## Canonical surface temperature El Nino response

## Canonical precipitation El Nino response

## CPC temperature forecast for DJF 2002-03

- Made mid-November

## IRI temperature forecast for DJF 2002-03

- Made mid-November

## DJF 2002-03 Observed SST Anomaly

## X

**X**

**X**

**X** **= ****significant error**
**in IRI’s SST forecast**

**X**

## Slide 13

## Slide 14

**Notes:**
Sfc. Temp. over NA

## Slide 15

**Notes:**
Precip over NA

##     CDC

**    ****CDC**
**     ****DJF 2002-03**
**From observed SST**

## From NOAA Climate Prediction Center

- wow

- wow

- gee whiz

## Sign-Agreement Diagrams 

- Sign-Agreement Diagrams
- 200mb height

- 5 models
- plus obs

- 5 models

## Signal-to-Noise

**Notes:**
Signal-to-noise ratio for different models.  Noise is approximated as the total variance (and not the internal....it could be corrected at a later stage)

## “Noise”

- “Noise”

**Notes:**
Total variance .... Used as an estimate for noise in the previous plot

## Signal-to-Noise

**Notes:**
Comparison of signal-to-noise between the Obs (top panel) and the average of signal-to-noise for the models (bottom panel).  If we think that model S-to-N has some realism, then there should be some (probabilistic) relationship between the observed S-to-N and the one estimated from AGCMs.  For example, if S-to-N is 2 (as in the tropics), there is high probability that the observed anomalies should be of the same sign (and have a similar S-to-N).

## Signal-to-Noise

**Notes:**
Scatter plot of S-to-N from the previous figure.  Bottom one is over NH 20N-70N latitudes (needs to be redrawn)

## Individual ensemble members

-     from the various models

- Ens
- Avg

**Notes:**
Correlation between the observed NDJF 200-mb heights and individual AGCM simulations

## Slide 24

**Notes:**
Frequency plots of correlations in the previous plot

- 200mb

- 200mb

- 200mb

- 200mb

- 200mb

- 200mb

- 200mb

## Toward AGCM-generated

- Fraction of ensemble members having positive anomaly
- (deviation from 0.5)

- 200mb

**Toward AGCM-generated**
**probability forecasts**

## Fraction of ensemble members having positive anomaly

- (deviation from 0.5)

- 200mb

## Fraction of ensemble members having positive anomaly

- (deviation from 0.5)

- 200mb

## Fraction of ensemble members having positive anomaly

- (deviation from 0.5)

- 200mb

## Fraction of ensemble members having positive anomaly

- (deviation from 0.5)

- 200mb

## Fraction of ensemble members having positive anomaly

- (deviation from 0.5)

- 200mb

## Fraction of ensemble members having positive anomaly

- (deviation from 0.5)

- 200mb

##  2000-01                        2001-02                       1997-98

-  2000-01                        2001-02                       1997-98

-      NDJF                            NDJF                           NDJF

-  5 models                      5 models                      5 models
-  + obs                            + obs                           + obs

- 5 models                     5 models                      5 models

## Reliability Diagram

-          1997-2001

## Reliability Diagram

- longer “AMIP”
- period
- from Goddard
- et al. 2003
- (EGS-AGU-EUG)