Climate Change:A National and Marine

Perspective

David WoolfNational Oceanography Centre, Southampton

Outline• Global/Regional Warming and Sea Level Rise

– Temperature Change– Sea level Change

• Changes in Weather Patterns– Changes in Occurrence– Changes in Wave Heights

• THC Collapse– Ocean Circulation– Temperature Change– Sea Level Change

• Summary

Global Sea Level Rise

Changes in Weather Patterns

Our Variable Winters: The NAO

• Strong influence on European Climate• Not necessarily connected with Global Change• Definite influence on many surface parameters

Variability in Wintertime Wave Climate

• Variations in wave height coherent over large distances in response to major modes of atmospheric variability

• North Atlantic Oscillation, NAO

• East Atlantic Pattern, EAP

NAO

EAP

Variability in Weather Patterns • Future Climate

Changes can be expressed as changes in main patterns, e.g.

• North Atlantic Oscillation, NAO

• East Atlantic Pattern, EAP

• NAO predicted to go positive

THCCollapse?

Slowing of Atlantic conveyor:

~30%

0

5

10

15

20

25

Volume transport

(Million cubic metres per

second)

1957 1981 1992 1998 2004Year

~30%

After Bryden et al (Nature, 2005)

Combined effect of Greenhouse Gases and THC Collapse

Sea Level Rise with THC Collapse

Summary• Global Warming is Real• But the detail is uncertain. Expect the

Unexpected• Probable outcomes include sea level

rise and an increase in storminess. Thus affecting

Coastal DefencesOffshore EngineeringRenewable Energy