The science of climate change

Sir David King

Chief Scientific Adviser to HM Government

British Council/Warsaw University Centre for Environmental Studies

30 March 2005

                                                                                                                                   

                   

Source: NASA

The earth’s energy budget

Carbon cycles

Glacial cycles of past 800,000 years

Source: Nature Vol 429

Source University of Berne and National Oceanic and Atmospheric Administration

Carbon dioxide levels over the last 60,000 years

379ppm 2004

Simulated global warming

Observed

simulated by model

Tem

pera

ture

ris

e

deg

rees C

0.0

0.5

1.0

1850 1900 1950 2000

Source: Hadley Centre

Annual European summer temperatures

1900 1950 2000

4

3

2

1

0

Tem

per

atu

re a

no

mal

y (w

rt 1

961-

90)

°C

Summer 2003 value

Annual averageSmoothed trendModel – natural factors only

Source: Hadley Centre

Possible flooding in the UK by 2080s

Foresight Flood and Coastal Defence Project – key findings

• Continuing with existing policies is not an option – risk becomes unacceptable levels in 3 of the 4 scenarios considered

• The risks can be reduced to present day levels using a broad portfolio of responses

• There are difficult decisions to be taken:– Invest more in sustainable approaches– Adapt to increased flooding

Mitigation - creating a low carbon economy

• UK White Paper published February 2003. Overall objectives are:

– To put the UK on a path to cut CO2 emissions by some 60% by 2050, with real progress by 2020

– To maintain the reliability of energy supplies– To promote competitive markets in the UK and

beyond– To tackle fuel poverty

…and a diverse mix of renewables

Improved energy efficiency…

G8 and EU challenges• Climate Change is a UK priority for G8 and

EU Presidencies in 2005 (African development is the other key priority)

• Climate change is a global problem and requires a global response– Kyoto, European Emissions trading

• Clear vision of energy futures required to enable global collaboration to move forward

• Science, engineering and technology have key roles to play