Climate risks and adaptation in Asian coastal megacities: A synthesis

More documents

Recommendations

Info

Table 4.16 ■ Proposed Implementation Arrangements for HCMCAuthorityHCMC DONREHCMC Environment Protection Agency (HEPA)Department of Planning and Architectureand its Institute for Urban PlanningDepartment of Construction with MOCLine departments and institutes responsiblefor (a) transport, (b) power supply, (c) watermanagement and supply, (d) water qualityand sanitation, (e) industry, (f) agricultureand fisheries, and (g) public healthHCMC Steering Committee for Flood andStorm ControlPriority actions(i) Revise the HCMC land use strategy and action plan to incorporate climate change issues and adaptationmeasures(ii) Prepare assessment guidelines for reviewing sector and spatial plans adaptation requirements andconsistency with the city adaptation plan(iii) Prepare assessment guidelines for integrating adaptation in SEA and EIA when applied to developmentplans and project proposalsPrepare adaptation monitoring and audit guidelines to keep track of adaptation performanceRevise the HCMC urban strategy and plan to set out the spatial land uses, controls, and safeguardsfor adaptationRevise and pilot the Building Code in the city so that it responds to climate change(i) Audit existing infrastructure and development plans and orientations(ii) Retrofit adaptation measures in existing infrastructure(iii) Define sector-specific adaptation options(iv)Upgrade sector design standards(v) Prepare strategies and plans for the next development period so they address climate change(vi)Introduce monitoring, auditing, and reporting on adaptation performance(i) Support each commune and district in reviewing and revising their specific contingency plans toprotect and cope with more extreme flooding and storm events, and identifying the key assets andresidential areas that need to be protected, up to and including evacuation of residents if necessary(ii) Improve early warning systems for floods, storms, tidal conditions, and drought(iii) Support ports, airports, and rail authorities in developing contingency plans in the event of majorflood events(iv) Develop an early warning system for traffic and alternative transport routes in the event of floodsSource: ADB (2010).74 | Climate Risks and Adaptation in Asian Coastal Megacities: A Synthesis Report
5Conclusions andPolicy ImplicationsThe studies undertaken in the three cities showthe challenges faced by coastal megacitieswith respect to regional and global climatechange and variability. These studies highlight theimportance of achieving sustainability in urban areasthrough a better understanding of the relationshipbetween urbanization, local hydrological systems,and climate. All of the cities considered in this reportare megacities with (registered and unregistered)populations close to or greater than 10 million. Eachis a driver of national and/or regional economicgrowth and all depend on the capacity of local hydrologicalsystems—such as rivers and streams,watersheds, and wetlands—to provide a range ofservices that are critical to the sustainability of thesecities and its residents. Given that these are all coastalmegacities, they face increased climate-related riskssuch as sea level rise and increased frequency ofextreme events. In this chapter, we conclude byhighlighting key findings and policy implicationsthat would be useful for urban policy makers toconsider with respect to adaptation at the city level.Key Findings and Lessons forPolicy MakersMajor risks are posed by increasedtemperature and precipitation in coastalmegacitiesAll three cities are likely to witness increases intemperature and precipitation linked with climatechange and variability. In Bangkok, temperatureincreases of 1.9 ° C and 1.2 ° C for the A1FI and B1scenarios respectively are estimated for 2050 andare linked with a 3 percent and 2 percent increasein mean seasonal precipitation for the high and lowemissions scenarios. A flood that currently occursonce in fifty years may occur as frequently as oncein 15 years by 2050, highlighting the potential foran increase in the frequency of extreme events. InManila, the mean seasonal precipitation is expectedto increase by 4 percent and 2.6 percent for thehigh and low emissions scenarios. In HCMC, theaverage annual temperature is expected to rise by1.4 ° C in 2050 (with only slight differences betweenthe high and low emissions scenarios). Further, a20 percent and 30 percent increase in precipitationis expected for a 1-in-30-year and a 1-in-100-yearevent respectively under the high emission (A2)scenario. While extreme rainfall linked with stormsis expected to become more common, preliminaryanalysis suggests that the frequency of dry seasondrought in HCMC is also likely to increase by 10percent under the low emissions scenario. Theserisks need to be recognized and better understoodby urban planners in the context of specific coastalcities, particularly in developing countries.Increase in flood-prone areas due to climatechange in all three citiesIn all three megacities in 2050, there is an increase inthe area likely to be flooded under different climatescenarios compared to a situation without climatechange. In Bangkok, for instance, under the conditionsthat currently generate a 1-in-30-year flood butwith the added precipitation projected for a highemissions scenario, there will be approximately75
Page 4 and 5:
© 2010 The International Bank for
Page 7 and 8:
Figure 4.6 Damage Costs Associated
Page 9:
AcknowledgmentsThis synthesis repor
Page 13 and 14:
Executive SummaryIntroduction and R
Page 15 and 16:
For each city, complex hydrometeoro
Page 17 and 18:
infrastructure but a high emission
Page 19:
these include strategies that focus
Page 23 and 24:
policy implications have broader re
Page 25:
2Methodologies forDownscaling, Hydr
Page 28 and 29:
Table 2.1 ■ Climate Change Foreca
Page 30 and 31:
Return periods considered 18In this
Page 32 and 33:
Figure 2.2 ■ Manila Rainfall-Runo
Page 34 and 35:
Figure 2.3 ■ Estimation of Damage
Page 36 and 37:
sion and distribution lines, and en
Page 38 and 39:
Figure 2.5 ■ Possible Relationshi
Page 40 and 41:
prices and the same prices are appl
Page 43 and 44: 3Estimating Flood Impactsand Vulner
Page 45 and 46: Table 3.2 ■ Bangkok Monthly Avera
Page 47 and 48: Estimation of storm surge in the ca
Page 49 and 50: Climate Change Impact and Adaptatio
Page 51 and 52: Figure 3.5a ■ Affected Condensed
Page 53 and 54: Manila’s current climate—Tropic
Page 55 and 56: Table 3.6 ■ Manila Climate Change
Page 57 and 58: Figure 3.10 ■ Areas of High Popul
Page 59 and 60: is also a key economic and financia
Page 61 and 62: Box 3.3 ■ HCMC in 2050Future land
Page 63 and 64: original swamp land on which the ci
Page 65 and 66: from 68 percent to 71 percent; that
Page 67 and 68: Table 3.15 ■ Districts Affected b
Page 69 and 70: Table 3.16 ■ Effects of Flooding
Page 71 and 72: 4Assessing Damage Costsand Prioriti
Page 73 and 74: Table 4.2 ■ Summary of Flood and
Page 75 and 76: uilt outside the cities and are not
Page 77 and 78: ■■■■■■For the eastern p
Page 79 and 80: Table 4.6 ■ Flood Damage Costs Wi
Page 81 and 82: Table 4.8 ■ Flood Damage Costs in
Page 83 and 84: Figure 4.5 ■ Loss Exceedance Curv
Page 85 and 86: Box 4.3 ■ Increased Time Costs an
Page 87 and 88: Table 4.11 ■ Adaptation Investmen
Page 89 and 90: Marikina River areas through a dam,
Page 91 and 92: Table 4.14 ■ Present Value of the
Page 93: of reducing vulnerability of the po
Page 97 and 98: open land use is expected to be flo
Page 99 and 100: hydrometeorological data, yielding
Page 101 and 102: BibliographyAllen, M. R., and W. J.
Page 103: Reduction: Inventory and Prospect.
Page 106 and 107: a paper commissioned by JICA (Sugiy
Page 108 and 109: mercial and industrial establishmen
Page 110 and 111: ADB. The selection and prioritizati
Page 113 and 114: AnnexCAdaptation to IncreasedFloodi
Page 115: of people and institutions to manag
Page 120: THE WORLD BANK1818 H Street, NWWash
show all

Climate risks and adaptation in Asian coastal megacities: A synthesis

Create successful ePaper yourself

Delete template?

Save as template?