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(c) Thanh Phuong
Ca Mau, the southmost tip of Vietnam
Coastal areas in the Greater Mekongregion are particularly vulnerable tothe impacts of climate change. Topredict how these areas will beaffected, their socioeconomic andenvironmental contexts must also beunderstood. .
In early 2008, the WWF GreaterMekong Prog ramme (GMP) ,w i t h s u p p o r t f r o m W W F ’ sMacroeconomics Programme,collaborated on a pilot study toassess climate change vulnerabilityand its implications for economicdevelopment in coastal areas. Twoprovinces - Krabi in Thailand andCa Mau in Vietnam - were chosenas different examples of coastalgeomorphology and economy.
These studies were unique in that for the first time they engaged local stakeholders to explore potentialimpacts on a variety of sectors using regional scale climate models applied at an appropriate local scale.
A World Bank report (02/2007) put Vietnam, a nation of 86 million people, atop its list of countriesmost vulnerable to the impacts of climate change. WWF’s Ca Mau study confirms at a local level thehigh degree of vulnerability noted by the World Bank. Findings from the Ca Mau study have not only
Assessing the Implications of
Climate Change at the Provincial Level: Ca Mau, Vietnam
Assessing the Implications of
Climate Change at the Provincial Level: Ca Mau, Vietnam
informed local and regional planners, but also guided the team thatis developing Vietnam’s National Target Programme for ClimateChange (NTP). More than 50 stakeholders, including seniormembers of Vietnam’s NTP preparatory team, met in Ca Mau inJune 2008 to review a draft version of this study. .
is a region of rich alluvial soils, carried there bythe Mekong River system from as far away as Tibet. But evenwhen the seas that wash Ca Mau on either side are quiet, themargin of safety for its 1.2 million people is thin – all ofthis 5,329km province at Vietnam’s southern tip is, on average,only one meter above sea level. .
Rice production, fisheries and, more recently, a booming shrimpaquaculture sector are well-developed in Ca Mau, and in 2005contributed roughly half of its economic output. Ca Mau plannersexpect rapid growth in the industry and construction sectors overthe next two decades. .
Land use zoning for agriculture, aquaculture and other sectors isbased on spatial control of fresh, brackish and salt water. This isaccomplished by a system of canals, sluices and dikes thatsupply fresh water and sediment and limit saline intrusion.
Ca Mau Province
2
Ca Mau Province, Vietnam
Ca Mau at sunrise
(c) Sinhcafe-JSC
Planning for climate change will require radical adjustments to ‘business as usual’. Regionalcooperation will be essential because administrative boundaries do not coincide with hydrologicalboundaries. The study specifically encourages planners to: .
In summary, this study underlined the major challenges climate change will pose to Ca MauProvince. Careful planning, based on rigorous science and involving all stakeholders, will befundamental to ensure sustainable development for the province’s people and ecosystems.
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WWF also urges regional cooperation to ensure that (i) changes in land-use reduce the vulnerabilityof people and biodiversity to climate change impacts; and (ii) sediment inputs from the entireMekong basin, continue to reach Ca Mau and the rest of the delta to counter the effects of risingseas. .
Further explore emergency evacuation options (e.g., early warning systems, communityeducation, and evacuation planning) as well as resettlement of vulnerable households inclusters on higher ground, with electricity, safe water, and efficient drainage; .
Develop sound water management strategies that rely on ‘soft structures’ (e.g., dunerestoration, wetland creation, re-vegetation); .
Improve understanding of how hydro-geological processes and human activities affectthe vulnerability of Ca Mau’s ecosystems; and .
Improve understanding at local and basin-wide levels of the role of forest ecosystemservices in adaptation, and especially the economic benefits that healthy forests providethe province. .
However, the dry season (January toApril) is characterized by freshwatershortages, soil salinization, and, inthe peat forest area, leaching of sulfuricacid. Thus the province relies onflooding from the lower Mekong duringthe monsoon season (May to December)to flush out salt and sulfates and providerich sediments and freshwater foragriculture and aquaculture. .
Ca Mau is also home to 37% ofVietnam’s remaining mangrove forestand to the Lower U Minh Forest, a vastfreshwater peat swamp. Twenty two percent of the province’s 1,080km2 of forest
(c) Thanh PhuongInfrastructure
.
Household sector
.
. Interior fields, secondaryembankments and canal banks are likelyto suffer the worst impacts as sea levelsrise. In high SLR scenarios, most roadswill be unusable in the wet season.
. In general, urbanhouseholds have better access to healthand civil infrastructure and hence are lessvulnerable to climate change risk thanrural households. However, both urbanand rural households throughout theprovince would be impacted in high SLRscenarios. Poor people are most likely tosuffer the consequences of extremeweather events and rising sea levels, e.g.,limited fresh water availability, unsanitaryconditions, crop damage, and ecosystemdegradation.
Buildings
.
Institutional capacity
Mangrove restoration is critically important
.
. In high SLR scenarios, Ca Mau’s existing hospitals, clinics and first aid stations will besubject to some flooding. Similarly, the province’s industrial sector is concentrated in low-lying areas,raising concerns about water contamination by industrial pollutants.
. There are very significant vulnerabilities for Ca Mau Province, yet some ofthese impacts may be mitigated if regional planners act urgently. For 2,000 years, the Vietnamesehave been dealing with the consequences of monsoon flooding and the typhoons that regularlybatter their long coastline. A tradition of community cohesion, reliance on local expertise and acentralized management system gives reason to believe that once national consensus is reached,
appropriate strategies can be swiftly and efficiently implemented .
. Simply reinforcing the province’s dike and drainagesystems will not be sufficient to ward off major climate change impacts. The most promisingapproach is one that derives full benefit from natural (ecosystem) defenses. Healthy mangroveforests will buffer Ca Mau’s coasts against storm surges. Seasonal flooding must continue todeposit rich sediments and flush contaminants from Ca Mau’s soil.
In Ca Mau, great swathes of mangrove forests have been replaced by diked ponds for shrimpproduction for global markets. Shrimp aquaculture has brought new wealth to the province,substantially raising incomes for thousands of farm families, but it has also degraded Ca Mau’s
Impacts and Implications .
.
.
resistance to destructive storms. This wastragically apparent in 1997, when TyphoonLinda ripped through the province, flatteningentire communities, leaving tens ofthousands homeless, wreaking havoc onripening rice, and smashing roads, dikes andbridges.
Incorporating the buffering capacity and othervital services provided by coastal ecosysteminto Ca Mau’s planning for mitigation ofclimate change effects is urgently needed.Because rising sea levels will stimulatelandwards migration of mangrove forests,care should be taken to site roads and watercontrol infrastructure to permit their retreat.
Mangrove forest cleared for shrimp farming for export
(c) Elizabeth KEMF / WWF-Canon
Ca Mau National Park boasts many rare and precious animals,including long-tailed macaque and grey-legged pelican
Ca Mau wet season water levels in 2030 underthe 50cm SLR scenario, shown here, wouldincrease further due to storm surge
has protected status. U Minh shelters the hairy-nosed otter, the Sunda pangolin and other criticallyendangered species. One hundred and eighty seven bird species have been recorded, including 9globally threatened species. .
.
WWF chose Ca Mau for this study because it is a low-lying coastal province where importantbiodiversity exists alongside significant economic activities such as fisheries, aquaculture andagriculture. Emphasis was placed on understanding the potential impacts of climate change on localpeople’s lives, which are linked to natural resources and ecosystem services. The study was carriedout by WWF in partnership with Vietnam’s Southern Institute for Water Resources Planning (SIWRP).The WWF/SIWRP team used a sophisticated hydrological model of the lower delta area to simulatewater levels and salinity based on predicted changes in climate over the next 10 and 25 years. Elevenscenarios were developed based on the changes in climate expected to cause the most significantimpacts in the province: sea level rise; extreme events; and storm surges. The scenarios were thenanalyzed with regard to future economic development, using the current provincial development planas a baseline. .
Design of the Study
Forestry sector. Ca Mau’s 1,460km of forests,concentrated on the western coast, the southern tip,and between the coast and sea dike system on the easterncoast, will be negatively affected in any climate scenario.
2
Without adaptive responses and measures to mitigateclimate change impacts, the threat to the province is high inall key sectors. Overall, the study indicated that low (25cm)sea level rise (SLR) scenarios can be managed within theframework of the existing provincial development plan, withan important caveat: greater attention must be given tomaintenance of ‘hard’ and ‘soft’ water management systemsand adaptation in farming and aquaculture techniques. High(50cm) SLR scenarios can only be managed through afundamental restructuring of the provincial development plan
. Ca Mau has 3,710km of landdevoted to agriculture and 2,270km used foraquaculture, particularly shrimp -- a profitable but riskyactivity. Modeling indicates that major adverse impactson productivity in all three cropping seasons will result ifSLR reaches 50cm. Existing aquaculture areas wouldbe especially hard hit by SLR.
The Modeling Results .
Farming sector 2
2
W E
N
S
Max water level in wet season
of ca mau province
Scenario b4
U Minh
Th¸i B×nh
Cµ Mau
TrÇn V¨n Thêi
C¸i N íc
¤ng §èc
Phó T©n
N¨m C¨n
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
Gu
lto
fT
hailan
d
South
Chin
aS
ea
Water level (m)
Southern Institute for Water Resources Planning0 25 50
Source: ICEM
Ho Chi MinhCity
People displaced-number by commune
<1000
1,001-2,500
2,501-7,500
7,501-15,000
>15,000