1. Overview Aims Data Methods Results CRU Symposium on Weather Extremes, 2 April, 2003 Observations of Extreme Temperature Events

2. Aims Analysis of observed daily time series Relate changes in extremes to changes in mean Seek relationships between extremes of temperature and precipitation and extremes of circulation Validation of GCM extremes CRU Symposium on Weather Extremes, 2 April, 2003 Observations of Extreme Temperature Events

3. Data Central England Temperature (max. and min. series) IMPROVE European Temperature Data UKMO gridded daily SLP fields (10 o x 5 o ) UK daily precipitation data (station & regional) CRU Symposium on Weather Extremes, 2 April, 2003 Observations of Extreme Temperature Events

4. Methods Gamma distribution defined percentiles - 4 extreme series Frost day extremes Spell days CRU Symposium on Weather Extremes, 2 April, 2003 Observations of Extreme Temperature Events

5. Results - Extreme Trends CRU Symposium on Weather Extremes, 2 April, 2003 Observations of Extreme Temperature Events CETMIN10 CETMIN90 CETMIN10 (spells) CETMIN90 (spells) CETMAX10 CETMAX90 CETMAX10 (spells) CETMAX90 (spells)

6. Results - Spell Lengths CRU Symposium on Weather Extremes, 2 April, 2003 Observations of Extreme Temperature Events

7. Results - Circulation CRU Symposium on Weather Extremes, 2 April, 2003 Observations of Extreme Temperature Events Gridded daily SLP fields 3 air flow indices - flow strength, vorticity & flow direction (Jenkinson & Collison)

8. Results - Circulation CRU Symposium on Weather Extremes, 2 April, 2003 Observations of Extreme Temperature Events

9. Results - Circulation CRU Symposium on Weather Extremes, 2 April, 2003 Observations of Extreme Temperature Events

10. Results - Circulation CRU Symposium on Weather Extremes, 2 April, 2003 Observations of Extreme Temperature Events

11. Results - Circulation CRU Symposium on Weather Extremes, 2 April, 2003 Observations of Extreme Temperature Events