Dr. Gomes Presentation at 2nd youth forum

Empowering our Youth for a Sustainable Society

Climate Change in the Caribbean- what can we do?

Charmaine Gomes Ph.D.

United Nations Economic Commission for Latin America and the Caribbean Subregional Headquarters for the Caribbean

Port – of – Spain, Trinidad and Tobago

4 August 2012

Structure of the Presentation

• Paleoclimatology and climate forecasting;

• The IPCC;

• The Stern Review

• Changes in Climate and Impacts on Key sectors

• The response – what can we do?

What is Paleoclimatology?• This is the study of ancient climates from:

– Tree rings;

– Glacial ice cores;

Last major advance of glacial ice

Compiled by R.S. Bradley and J.A. Eddy based on J.T. Houghton et al., Climate Change: The IPCC Assessment, Cambridge University Press, Cambridge, 1990 and published in EarthQuest, vo. 1, 1991. Courtesy of Thomas Crowley.

So far in the past 18,000 years, the earth's temperature has risen

approximately 16 ° F and the sea level has risen 300 feet.

Glaciers retreat & SL rises

The World 18,000 Years Ago

Our Present World

A schematic reconstruction (solid line) of mean global surface temperature through the last 100 million years, based on analyses of various marine and terrestrial deposits. The dashed-line extension is a prediction of future trends through the coming 400 years, based on the assumption of substantial utilization of the fossil fuel reservoir. The vertical line shows the approximate range of surface temperature in climate model predictions for a doubling of CO2 levels, at about 100 years in the future. Modified from T. J. Crowley, Journal of Climate, vol 3,

pp 1282-1292, 1990.

IPCC - Main Findings• Global conc. of CO2, CH4 and N2O have

increased since 1750 – human activity;

• CO2 increases are due to fossil fuels use and land use change;

• CH4 and N2O increases – primarily due to agriculture;

• Increase in CO2 from 280 ppm to 379 ppm in 2005. Now it has reached 395.77

Main findings….• Warming of the climate is unequivocal;• Increases in global average air and ocean

temperatures;• Widespread melting of snow and ice;• Rising of global average sea level; 1.8

mm/year between 1961 and 2003;• Rate of SLR was faster between 1993 and

2003;• Changes in arctic ice and temperatures.

Main Findings….• Widespread changes in precipitation;• Change in ocean salinity;• Changes in wind patterns; • Increase in extreme weather events,

including droughts, heat waves;• Changes in sea surface temperatures;• Changes in tropical hurricane activity in

the north Atlantic since about 1970 correlate with increases in sea surface temperature

IPCC Projections

• For the next 2 decades, a warming of about 0.20 C per decade is projected;

• Even if concentrations of GHG and aerosols are kept constant at 2000 levels a further warming of about 0.10C is expected;

• This would cause additional warming;

GLOBAL GHG EMISSIONS

•

Direct Regional Evidence• Temperature trend

– Temperature records have shown an increase in the last century, with the 1990s being the warmest decade since the beginning of the 20th century.

– 1998 also appears as the

warmest year on record.

• Rainfall trend– Records have shown

changing patterns.

– Floods in some areas and drought in other areas

Variations of land surface temperature for the Caribbean

Period1973 to 2000

BARBADOS TRINIDAD

SAINT LUCIA

DOMINICA

-0.8

-0.6

-0.4

-0.2

0.0

0.2

0.4

0.6

0.8

197

0

197

3

197

6

197

9

198

2

198

5

198

8

199

1

199

4

199

7

200

0

200

3

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

1960

1963

1966

1969

1972

1975

1978

1981

1984

1987

1990

1993

1996

1999

Period1973 to 2000

BARBADOS TRINIDAD

-0.8

-0.6

-0.4

-0.2

0.0

0.2

0.4

0.6

0.8

1.0

1973

1976

1979

1982

1985

1988

1991

1994

1997

2000

-2.5

-2.0

-1.5

-1.0

-0.5

0.0

0.5

1.0

1974

1977

1980

1983

1986

1989

1992

1995

1998

2001

2004

Saint Lucia

Dominica

Caribbean Sea Temperature Much Warmer

• Warmer sea temperatures support:

– Development of stronger hurricanes at lower latitudes

– More rapid transition to category 4 and 5

– Increases the likelihood of coral bleaching

April sea temperature near 80oF/27oC

Model Projection of Future Increases in the Regional Temperatures

WARMER SEA TEMPERATURES RESULT IN CORAL BLEACHING AND MORTALITY

• In 1998 coral reefs around the world suffered the most extensive and severe bleaching and subsequent mortality in modern record.

• In the same year, tropical sea surface temperatures were the highest in modern record, topping off a fifty year trend for some tropical oceans.

• The repercussions of the 1998 mass bleaching and mortality events will continue to be far reaching in time and space.

Impact of 1oC further rise in sea temperature on the Yellow Tuna

Yellow tuna

Habitat becomes less favourable

+1°C+1°C

Green parrot fish

Habitat becomes less favourable

+1°C+1°C

Impact of 1oC further rise in sea temperature on the Parrot Fish

Dolphin fish

Habitat becomes less favourable

+1°C+1°C

Impact of 1oC further rise in sea temperature on the Dolphin fish

The Stern Review - Conclusions• If we don’t act, the overall costs and risks of CC will be

equivalent to losing at least 5% of global GDP per year;• If a wide range of risks and impacts is taken into

account, the estimates of damage could rise to 20% of GDP or more;

• Our actions now and over the coming decades could create risks of a disruption to economic and social activity, on a scale similar to those associated with the great wars and the economic depression of the 1st half of the 20th century;

• It would be difficult to reverse these changes;• The costs of stabilising the climate are significant but

manageable;• Delay would be dangerous and much more costly.

The Response - What can we do?• The costs of action – reducing GHG emissions can

amount to about 1% of GDP per year;

• The investment that takes place during the next 10 – 20 years would have a profound effect on the climate in the 2nd half of this century and the next;

• Response must be international;

• Must be based on a shared vision of long-term goals and agreement on frameworks that will accelerate action over the next decade;

• It must build on mutually reinforcing approaches at national, regional and international levels.

The Response - What can we do?..• Adaptation should be accelerated;

• Adaptation will cost tens of billions of dollars per year and will put pressure on already scarce resources but what of the costs of inaction?

• Need better information, improved planning and more climate-resilient crops and infrastructure;

• Central estimates of annual costs of achieving stabilisation between 500 and 550 ppm CO2 e are around 1% GDP; if we start to take strong action now;

• It would be difficult and costly to aim to stabilise at 450 ppm.

Final Conclusions• The evidence leads to a simple conclusion:

“the benefits of strong, early action considerably outweighs the costs”

• Other conclusions;• Ignoring climate change will eventually damage

economic growth.• Measures to help people to adapt are

essential.• The less mitigation we do now, the greater the

difficulty of continuing to adapt in the future.

Final Recommendation

• There is still time to avoid the worst impacts of climate change, if we take strong action now