professor a.e. hill director national oceanography centre, southampton uk oceans and global change
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PROFESSOR A.E. HILL
DIRECTOR
NATIONAL OCEANOGRAPHY CENTRE,
SOUTHAMPTON
UK
OCEANS AND GLOBAL CHANGE
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GLOBAL CHANGE
What does it mean?Ocean-atmosphere-ice system out of normal balance
Changes at an unprecedented rate (last 1 M yrs)
Why does it matter?
Global change impacts Europe
Local and regional impacts
Impacts on the Global economy
The oceans
are integral to understanding and predicting changes in the
global environment
OCEAN-ATMOSPHERE-ICE BALANCE
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• What is going on now ?
fundamental understanding of basic earth system processes
• Continuous awareness of change sustained observing
• What is going to happen next – especially locally ? predictive capability
• Finding solutions evidence based policy, regulation, technology solutions, innovations to grasp opportunities and minimise risks
LIVING ON A CHANGING EARTH: THE CHALLENGES FOR SCIENCE
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• SEA LEVEL CHANGE
• OCEAN ACIDIFICATION
• ARCTIC ICE THINNING
OCEANS AND GLOBAL CHANGE - HOT TOPICS
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MEAN SEA LEVEL CHANGESPast 200+ years observed, next 100 years predicted
global rise of approximately 10-20 cm during the past 100 years (IPPC 3rd Assessment Report)
IPCC Third Assessment ReportPermanent Service for Mean Sea Level www.pol.ac.uk/psmsl
Predicted 9-88 cm (central value 48 cm)
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OCEANS AND GLOBAL CHANGE
EXTREME SEA LEVEL EVENTS THAT CAUSES FLOODS
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COASTAL AREAS AT RISK
By 2100
The 1 in 100 year flood level (shown here in red) may become a 1 in 10 year level
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SEA LEVEL COMMITMENT – living with the consequences
Sea level will continue to rise even after CO2 emissions
are reduced
Third IPCC Assessment Report
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EUROPEAN SEA LEVEL OBSERVING NETWORK
(ESEAS)
www.eseas.org
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REDUCING UNCERTAINTIES: THE ABILITY TO PREDICT?
NORTHWEST EUROPE STORM SURGE SCENARIOS: Computed change in 50-year surge
Range of values -20 to +40cm.
Storm Surges with HADCM2 climateStorm Surges with ECHAM4 – T102
Source: Proudman Oceangraphic Laboratory www.pol.ac.uk
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Source: Sabine et al (2004) Science, 305:367-371
ATLANTIC
PACIFIC
INDIAN
OCEANOCEAN ACIDIFICATION ACIDIFICATIONFossil Fuel COFossil Fuel CO22 is invading the Ocean is invading the Ocean
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The Extra COThe Extra CO22 is Acidifying the Ocean is Acidifying the Ocean
Source:
Caldeira &
Wickett (2003)
Nature, 425:365
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Particular Concern for Organisms with Particular Concern for Organisms with Chalk Shells or SkeletonsChalk Shells or Skeletons
coral reefscoral reefs coralline algaecoralline algae
foraminiferaforaminifera
coccolithophorescoccolithophores
pteropodspteropods
Source:
Royal Society
report on ocean
acidification (2005)
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Malformed coccoliths at high COMalformed coccoliths at high CO22
Source: Riebesell et al (2000) Nature, 407:364-367
High CO2
Normal CO2
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OCEAN ACIDIFICATION
What We KnowWhat We Know1. Ocean acidification is already happening
2. If emissions continue oceans will inevitably become ever more acidic
3. Coral skeletons and chalk shells will be affected
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What We Need to Find OutWhat We Need to Find Out1. How will the organisms be affected by thinner shells and
weaker skeletons?
2. What other effects will follow from lowered pH?
3. What will be the knock-on effects on marine ecosystems and the ocean carbon cycle?
“Thus chemical effects of CO2 on the marine environment may be as great a cause for concern as the radiative effects of CO2 on Earth’s climate.” [Caldeira & Wickett (2005) J. Geophys. Res. 110, C09S04]
OCEAN ACIDIFICATION
FISH AND CHIPS or JELLYFISH AND CHIPS ?
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THE ARCTIC OCEAN: SHRINKING SEA ICE COVER
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Bad news for Polar Bears ... but also...
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RAPID CLIMATE CHANGE: The freshening of Arctic and sub-Polar seas
As the sea ice melts the Arctic ocean is freshening. This will lessen the production of dense salty deep water and could result in changes to the ocean circulation
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NORTHWEST EUROPE IS WARMER THAN IT SHOULD BE
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FRESHENING OF HIGH LATITUDE WATERS COULD SLOW SINKINGAND RELEASE OF HEAT TO THE ATMOSPHERE
The temperature rise/fall relative to pre-industrial for the first decade after a collapse in 2050
(Hadley Centre)
With a simple model the probability of collapse by 2100 is about 30%
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RAPID CLIMATE CHANGESCIENCE FOR DEVELOPING A LONG TERM OBSERVING SYSTEM FOR ADVANCE WARNING
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WHO WILL EUROPE‘S MAJOR TRADING PARTNER BE IN
2025? Will Europe increasingly face north?
Economic, Social and Environmental implications?
The North West Passage in September 2005
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MARINE SCIENCE
THE GLOBAL ENVIRONMENTAL CHALLENGES FACING EUROPE: SOLUTIONS THROUGH PREDICTION - NOW IS THE TIME TO INVEST
Big questions• Massive implications (environmental, social, economic)• Fundamental marine science at the heart of these
Addressing• What is going on now ?
• How can we be more continually aware of changes ?
• What is going to happen next?
• What solutions can help us live with a changing world?
Needing• A healthy marine science base (people and the major infrastructure to support marine science)
• Robust approach and funding mechanisms for sustained marine observing
• Well focussed coordinated marine science programmes
• Strong knowledge transfer - marine science into policy and business opportunity
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CONCLUSIONSWE LIVE ON A PLANET NOW OUTSIDE ITS NATURAL RANGE AND CHANGING AT AN UNPRECEDENTED RATE
• The Oceans are integral to understanding global change
• The consequences of global change for Europe present both risks and opportunities
• Key to preparation is better sustained observation and prediction of marine systems
• Coordinated research to inform policies at European level and to give European businesses the competitive edge is vital
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OCEANS AND GLOBAL CHANGE