1. Climate Change in Scotland / UK / N. Europe
David Stevenson
Institute of Atmospheric and Environmental Sciences
University of Edinburgh

2. Main sources of information
IPCC Climate Change 2007:
The Physical Science Basis, Summary for Policymakers (WGI-SPM)
Also leaked 2nd drafts of full report (Draft WGI)
Climate Change Impacts, Adaptation and Vulnerability (WGII-SPM)
UK Climate Impacts Program 2002
The UKCIP02 Briefing Report (UKCIP02)

3. Two key quotes from IPCC (2007) WGI-SPM
“Warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global average sea level.” “Most of the observed increase in globally averaged temperatures since the mid-20th century is very likely* due to the observed increase in anthropogenic greenhouse gas concentrations.”
*In IPCC parlance, ‘very likely’ is >90% chance

4. WGI-SPM Scottish Temperature 1914-2005 Thames Barrier Usage 1982-2003
(Scottish Executive, 2006)
Thames Barrier Usage
(King, 2004)
(Palutikof, 2000)
WGI-SPM

5. Spring is getting earlier!

7. 90-95% of all changes are consistent with warming
IPCC 2007
SPM-WGII

8. Northern Europe likely to warm by 2 to 5C by 2100
WGI-SPM
Draft WGI

9. UKCIP02 Changes in temperature
In 2002, UKCIP study indicates Scotland will warm by C

10. Annual
Winter
Summer
Temperature
Precipitation
WGI-SPM
Draft WGI

11. Changes in precipitation
UKCIP02, High emissions case (A1FI) ( vs ) 1 Model: Hadley Centre Regional Model
Annual
Winter
Summer
IPCC 2007, draft WGI – Chapter 11 – Regional Modelling A1B scenario, 2080/90s relative to 1980/90s; 21 Models

13. Draft WGI
Some models predict large increases in higher percentiles of GB summer maximum temperatures, i.e. much more severe heat-waves
UKCIP02

14. Extreme events also crucial for coastal flooding…

16. Summary of robust findings from regional modelling from the draft IPCC WGI, for mean and extreme precipitation, drought, sea-ice, extreme winds, and tropical cyclones.

17. Rainfall is more intense
Summer (JJA)
Less rainfall in summer, more rainfall in winter, but UK is near boundary between increases/ decreases, so relatively uncertain.
Rainfall is more intense
in both seasons, i.e. increased likelihood of flash-floods.
Winter (DJF)

18. Summary
Scotland likely to warm ~2.5C by 2100 (also more extreme heat-waves)
Winter precipitation increases (~10-15%)
Summer precipitation decreases (~5-10%)
Precipitation intensity increases – flash-floods
Snow declines; Wind-storms increase?
Sea-level rise partly mitigated by uplift (~30-40cm) – coastal floods
Although prognosis is bad, Scotland is perhaps relatively the least impacted region of N. Europe?