Climate Change and Climate Variability: Implications for SIDS

UNESCO International Seminar on Climate Change Education

Paris, July 27-29, 2009

Leonard NurseSenior Lecturer, Centre for Resource Management and Environmental Studies

(CERMES), Faculty of Pure and Applied SciencesUniversity of the West Indies (UWI), Cave Hill Campus, Barbados

leonard.nurse@cavehill.uwi.edu

Status of the Climate Change Debate

• There is NO disagreement among scientists about whether the climate system has become measurably warmer.

• There is also wide, global consensus about the cause of the warming experienced in the last 150 years or so.

Change in LongChange in Long--Lived GHGs, 1750Lived GHGs, 1750--2005 2005 Greenhouse

Gas1750 (Pre-

Industrial Era) 2005 % Change

Carbon Dioxide (CO2)

278 ppm 379 ppm 73

Methane(CH4)

715 ppb 1774 ppb 40

Nitrous Oxide(N2O)

270 ppb 319 ppb 85

Atmospheric concentrations of CO2, CH4 and N2Oand their rates of increase are considerably greater

than anytime in at least the last 10,000 years

Carbon dioxide Nitrous Oxide

Global mean temperatures are rising faster with time

100 0.074±0.01850 0.128±0.026

Warmest 12 years:1998,2005,2003,2002,2004,2006, 2001,1997,1995,1999,1990,2000

Period Rate

Years °/decade

Pasterze Glacier, Austria, 1875-2004(University of Innsbruck Archives)

Changes in Arctic Sea Ice (NASA)

Snow and ice accumulation on Mt. Kilimanjaro have contracted by approx. 80% since 1900

(Photos: NASA – Earth Observatory)

Mean Sea Level 1870 Mean Sea Level 1870 –– 2003, relative to 19612003, relative to 1961--1990 mean1990 mean::Red = reconstructed sea level from all available sources; Red = reconstructed sea level from all available sources;

Blue = tide gauge data since 1950; Black = satellite altimetry Blue = tide gauge data since 1950; Black = satellite altimetry postpost--1992 (Source: IPCC, 2007)1992 (Source: IPCC, 2007)

Observed Sea Level Rise in The Main Regions of SIDS (IPCC AR 4)

Region Mean Rate of SLR Highest Rate of SLR

Caribbean Sea Approx. 1.0 mm yr-1

(20th Century)Southern Trinidad: approx. 4.0 mm yr-1

Indian Ocean Approx. 1.3 – 1.5 mm yr-1 ± 0.5 mm yr-

1 (1950-2001)

Maldives: Three stations ranging between 3.2 – 6.5 mm yr-1

Pacific Ocean Approx. 0.77 mm yr-1 Central & Eastern Pacific: 2.0 – 3.0 mm yr-1

Model Projections for SIDS Regions• Observed changes in Caribbean, Indian Ocean and Pacific

climate are consistent with global and hemispheric variations:

◘ Climate models suggest a consistent increase in surface air temperature for the SIDS Regions, over the next several decades.

◘ Observed and projected sea surface temperature increases in the main SIDS regions are also consistent with global trends.

◘ GCM model outputs and observational records suggest a consistent drying trend in the Caribbean.

◘ Increase in tropical cyclone (hurricane) maximum wind intensity - at least 5 -10 % before the 2050s, is projected.

Projected Increase Air Temperature (0C) in Main SIDS Regions Relative to 1961-1990 Mean

Region 2010-2039 2040-2069 2070-2099

Mediterranean 0.6 - 2.19 0.81 - 3.85 1.2 - 7.07

Caribbean 0.48 – 1.06 0.79 – 2.45 0.94 – 4.18

Indian Ocean 0.51 – 0.98 0.84 – 2.10 1.05 – 3.77

Northern Pacific

0.49 – 1.13 0.81 – 2.48 1.00 – 4.17

Southern Pacific

0.45 – 0.82 0.8 – 1.79 0.99 – 3.11

Projected Annual Precipitation Change - Caribbean

Temperature Change Temperature Change –– Eastern Caribbean Eastern Caribbean (University of the West Indies Climate Modeling)(University of the West Indies Climate Modeling)

No. of No. of Days with Temp Days with Temp ≥≥ 3030ºº CCPresent Climate Future Climate

Extreme Temperature Change Extreme Temperature Change –– Eastern Caribbean Eastern Caribbean (UWI Climate Modeling)(UWI Climate Modeling)

No. of Days with Temp No. of Days with Temp ≥≥ 3535ºº CC

Future ClimatePresent Climate

What Are the Risks for SIDS?

• Small island communities are among the most vulnerable to climate change, and the impacts will be largely adverse.

• Many countries are already experiencing the negative effects of increased air and sea surface temperature and sea-level rise, which are affecting both natural ecosystems and socio-economic conditions.

• Small states including those in the Pacific, Caribbean and Indian Ocean have a low capacity to adapt to the negative impacts of climate change.

• In small islands, the cost of adaptation to climate change is high relative to GDP → disproportionately adverse effect on island and small state economies.

Ocean Absorption of CO2 and Acidification • The link between ocean warming and coral bleaching is well

established. Major bleaching events documented (e.g. 1983, 1997-98, 2005-2006) → ocean temperatures ≥≥ 10 C above summer maximum.

• Evidence of ocean acidification now being widely observed ◘ Limiting factor in shell formation. Corals and other marine

organisms use carbonate ions in sea water to build calcium carbonate shells. With rising CO2 emissions, more CO2 is absorbed by oceans, sea water becomes more acidic → more difficult for organisms to form shells

Consequences of Climate Change for the Caribbean Increased Risk of Coastal Erosion• Model runs and observed data consistently project that

accelerated beach erosion will be an inevitable threat facing small islands. While much present-day erosion is man-induced (sand mining, construction in active beach zone, infringement of building set-backs, etc.), empirical studies show that SLR is a significant contributory factor.

4Higher Water Levels + Higher Wave Amplitude = Increased Wave Energy

4 Recent coastal vulnerability assessments for Barbados, Guyana and Grenada (CPACC Project) clearly demonstrate that elevated sea level amplifies the rate of coastal erosion.

4 In Trinidad some beaches are retreating by as much as 1.0 m/ yr, where sea level has been rising at rate of 8-10 mm yr-1, during the past 15 years.

Agriculture and Food Security

• Projected impacts include extended periods of drought and reduced soil quality → increasing soil salinization.

► In studies of the Pacific Islands, World Bank (2000, 2002) found that ‘high’ islands such as Fiji could experience damages of US$ 23-52 M per year, by 2050. ‘Low’ islands such as Kiribati could face average annual losses > US$ 8 -16 M (≈17-18 percent of Kiribati’s GDP in 2002), as a result of climate change.

• Extreme events, e.g. hurricanes, floods, droughts →severe damage to crops, e.g. the case of Grenada after hurricane Ivan. Grenada’s most important commercial crop, nutmeg, was devastated in a few hours by the hurricane. Since the crop requires 7-8 years – no foreign exchange from this source for almost a decade.

Food Security in the CaribbeanCrop Modeling Results: The Impact of a Mean Temperature Increase of 2o C ± 20 % Change in Rainfall on Three Crops

Crop ScenarioSeason Duration (Days)

Temp. Change

(0C)

% Rainfall Change

Yield (kg/ha)

% Change in Yield

Rice (C3)

Baseline Carib A

124113

0+2

0+20

3355.53014.4 -10 %

Dry Beans (C3)

Baseline Carib A

878585

0+2+2

0+20-20

1353.61163.71092..6

-14 %-19 %

Corn (C4)

Baseline Carib A

1041139797

0+2+2+2

0-20+20-20

4510.62887.53736.63759.4

-14 %-22 %-17 %

Recent Hurricane Threat in the Atlantic• Four major hurricanes impacted the Caribbean basin in 2004,

causing more than US$ 4.0 billion.• 27 named storms in 2005, 15 of which became hurricanes. An

unprecedented 4 hurricanes reached category 5 status. • The current decade (2000–present) has already experienced

more category 5 systems than any other decade: Isabel (2003); Ivan (2004); Emily, Katrina, Rita, Wilma ( 2005); Dean and Felix (2007).

Economic Impact of the 2004 Hurricane Season in the Caribbean

Country Hurricane Losses (US$ m)

The Bahamas Frances and Jeanne 551

Cayman Islands Ivan 1,620

Dominican Republic

T.S. Jeanne 296

Grenada Ivan 889

Haiti Jeanne 296

Jamaica Ivan 595

Total 4,247

Water Resources• Water resources on islands are especially

vulnerable to changes in rainfall distribution. A reduction in average rainfall will adversely affect (a) seasonal and annual availability (b) river flow and (c) rate of recharge of the freshwater lens → water scarcity.

• Modeling of future water availability on several islands based on a macro-scale hydrological model (UKMO HADCM2) found that (a) most islands would be exposed to severe water stress and (b) many islands will be unable to meet future demand by the 2050s, some as early as 2025.

• Some countries (e.g. The Bahamas, Antigua and Barbuda, Maldives, Seychelles, Tuvalu)have begun to invest in adaptation strategies, e.g. desalination - to offset current and projected water shortages.

Increased Rates of Beach/Coastal Erosion

• Accelerated beach erosion will be a major challenge in the Caribbean. While some present-day erosion is man-induced (sand mining, reef degradation, etc.), empirical studies show that sea level rise is a significant contributory factor.

4Higher H2O Levels → Higher Wave Amplitude → Increased Wave Energy = More Coastal Erosion

4 Coastal vulnerability assessments for Barbados, Guyana and Grenada (CPACC Project) show that elevated sea level amplifies coastal erosion.

Storm Surge, Flood Risks and Inundation

• Flood risk modeling (HADCM2, HADCM3, UKMO, 1999) suggests that by 2080, numbers facing severe floods in the Caribbean, Indian and Pacific Ocean regions would be 200 times higher than if there were no SLR.

• Studies in Cuba (Perez et al. 1999, based on HADCM2), identified 98 coastal settlements with a total population exceeding 50 000 persons, which would be completely inundated by a 1.0 m rise in sea-level.

Georgetown, Guyana, 2004 Georgetown, Guyana, February 2005

Climate Change and Fish Stocks• Bleaching of corals and loss of habitat• Changes in occurrence and intensity of ENSO events -

adverse effect on Pacific artisinal and commercial fisheries.

• Alteration of offshore and nearshore current patterns → e.g. 10 C increase in water temperature could alter migration patterns of species including skipjack and yellow fin tuna, mahi mahi (dolphin), parrot fish etc.

• Changes in reproductive habits of some fish populations.

Migration of Tuna

Tourism• Tourism is a major revenue earner and generates significant

employment. In many SIDS. The impact of climate change on this sector will be both direct and indirect.

◘ SLR will disrupt the sector through accelerated coastal erosion and beach loss, and likely damage to physical plant and vital infrastructure.

◘ The industry is also sensitive to other climate-related impacts, e.g. the loss of corals and other marine flora and fauna, which support passive, income-generating recreation, e.g. the scuba diving industry.

◘ The highest temperature changes are occurring in the middle-and high-latitudes. A large % of tourism is generated by the desire of visitors to ‘escape’ the cold winters of the North. Milder winter temperatures in these markets could reduce the appeal of the Caribbean as a tourist destination

Infrastructure and Housing• In the Caribbean, Pacific and Indian Ocean SIDS, more than

half of the population lives within 1.5 km of the coast. Housing, government offices, hospitals and critical utilities are frequently located close to the shore. Sea level changes and behaviour of storms → serious consequences for infrastructure.

• Almost without exception, regional airports are sited at or nearthe coast. Many major highways run parallel to the shore. With projected sea-level rise, much of this infrastructure would be at risk from flooding and physical damage.

• The threat from sea-level rise to infrastructure is amplified with the passage of tropical cyclones (hurricanes), e.g.

◘ Hurricane Lenny, Nov. 999 - storm surge damage in St. Lucia > US$ 6.0 million – even though system was a few hundred kilometres offshore.

Human Health• Climate change is likely to result in a higher incidence of vector-

borne diseases, e.g. dengue fever and malaria. The mosquito vectors as well as other environmental factors in disease transmission, are climate-sensitive.

• Shortages of fresh water and poor water quality during periods of drought, as well as contamination of fresh water supplies during floods and storms, also lead to an increased risk of disease, e.g. cholera and diarrhoea.

• There is increasing evidence that climate change appears to be extending the growing season for various types of pollen and other allergens → higher incidence of asthma and related conditions.

• Incidence of ciguatera fish poisoning is projected to increasewith warmer ocean temperatures.This will have an adverse effect onnutrition and human health.

Potential Economic Losses in the Caribbean Without Action to Reduce the Impact of Climate Change

(Source: Tufts University, 2008)

◙ Unless there is a meaningful post-Kyoto agreement, it is projected that :

• By 2025 the average cost to the region will be 14 percent of its GDP

• By 2050 the average cost to the region will be 39 percent of its GDP

• By 2075 - 45 percent of GDP

• By 2100 - 63 per cent of GDP

…So What Can SIDS Do?

….So What Can SIDS Do? • Climate change is a global problem that cannot be solved by

any single country. We must

►Continue to support the international efforts to implement an effective regime to reduce global greenhouse gas emissions to a level that minimizes economic, social and environmental dislocation → Insist on emissions reductions targets that would achieve climate stabilization.

►Continue to meet our obligations under the United Nations Framework Convention on Climate Change and the Kyoto Protocol → build the necessary capacity to enable us to access maximum benefits from facilities such as the ‘Adaptation Fund’and the Clean Development Mechanism (CDM).

Other Adaption Responses• There are other measures which, if implemented in a timely

manner, can reduce some of the risks:

¤ Infrastructural → e.g. erect coastal and flood protection (SLR & flooding); adopt technologies that improve water use efficiency, e.g. trickle irrigation

¤Behavioral: altered habits and choices → e.g.more fuel-efficient vehicles and wider use of public transportation

¤ Managerial → e.g. altered farm practices such as cultivation of drought-tolerant cultivars; implementation of demand management strategies (e.g. through metering and pricing)

¤ Government Policy → e.g. planning regulations; building codes; use of appropriate, renewable energy sources –solar, wind, bio-fuels, landfill gas (methane).

Thank You