Post on 20-Jan-2016
1
Nobuo Mimura
Institute for Global Change Adaptation Science Ibaraki University/IR3S
International Symposium “Cities at Risk”
Sea-Level Rise and Coastal Vulnerability
Contents of Presentation
1. Global and Regional Picture - Climate Change and Sea-Level Rise
2. Local and Individual Pictures - Mangrove erosion in Thailand - Cyclones in Bangladesh - Tsunami in Maldives - Coastal Protection in Tokyo
3. Challenges
1. Global and Regional Picture –Climate Change and Sea-Level
(IPCC AR4, 2007)
(IPCC WGI AR4, 2007)
Global Mean Sea-Level
- 17cm rise for the past 100 yrs- Present speed of SLR is 3.2 mm/yr.- In a long tem, collapse of Greenland ice sheet may induce 2-7m SLR.
5
Temperature Rise(2071~2100)
Tropical Cyclones 1949-2007
Estimated Typhoon Parameters
Maximum Wind Vel. [m/s]------
2030405060
172030405060
Lowest Cent. Press. [hPa]---------
860880900920940960980
1000
860880900920940960980
10001013
Lowest Center Pressure Maximum Wind Velocity
Severity of Typhoon Effect (Hot Spots)
Severity
Rank
１Rank
２Rank
３Rank
４Rank
５Rank
６Rank
７Rank
８Rank
９
Inundation by Local HWL(Tide)Inundation by Local HWL(Tide)
Inundation by Local HWL + SLR 59cmInundation by Local HWL + SLR 59cm
Inundation by Local HWL + SLR 59cm + 100yr Strom Surge
Inundation by Local HWL + SLR 59cm + 100yr Strom Surge
Asia362 million people (10.2% of 2000 pop.)
Population Growth in Asia
Vulnerability of Maga-deltas
・ Several millions more people will be flooded annually.・ Proactive and planned adaptation is necessary.
Extreme: >A million （ by 2050 ） High: 50 K to one million Medium ： 5K to 50 K
（ IPCC WGII AR4, 2007 ）
Case-1
Erosion of Mangrove
in Thailand
2. Individual Pictures
Landsat image around river mouth of Chaophraya
Erosion at the front
Land Subsidence in Bangkok Source:Somkid(2002)
Case-2
Tropical Cyclones in Bangladesh
Date Max Wind (m/s)
Max Wind Radius (km)
Storm surge (m)
Casualties（ peopl
e ）
30 Oct 1960 57.5 74 4.57-69.10 5,179
9 May 1961 40.8 64 2.44-3.05 11,468
28 May 1963 55.6 74 4.27-5.18 11,520
11 May 1965 58.1 74 3.66 19,279
31 May 1965 44.7 64 6.10-7.62 12,000
23 Oct 1966 40.3 64 6-6.67 850
12 Nov 1970 61.7 74 6.10-9.14 500,000
24 Nov 1974 44.7 64 2.8-5.2 200
9 Nov 1983 33.3 64 3.05-4.57 11,069?
25 May 1985 42.5 64 3.05-4.57 11,069?
29 Nov 1988 44.4 64 1.52-3.05 5708
29 Apr 1991 62.5 74 6.10-7.62 138,000
25 Nov 1995 58.3 74 - 650
19 May 1997 55.6 74 4.6 126
26 May 1997 41.7 74 3.0 70
16 May 1998 45.8 74 1.83-2.44 -
History of Cyclone Damages
Combining Early Warning System and Hard Measures
Cyclone Shelter (Chittagong Port City )
Evacuation Road to a Cyclone Shelter
Coastal Dike
(News Week Japanese 1/12)
Case-3 2004 Indian Ocean Tsunami- Coastal vulnerability and countermeasures
Male Island
(Preliminary Report of Survey Team, JSCE, April 2005)
埋め立て地と浸水地域の分布 (Preliminary Report of Survey Team, JSCE, April 2005)
Male Island
Case-4 Coastal Protection in Tokyo
Affected Pop (million)
HWL 2.3
HWL+SLR 3.2
HWL+SLR+SS 4.2
Increased Population at Risk in Tokyo
History of Flood Damage in Japan
Dead/Missing
Changes in Death Rate Due to Natural Disaster (1945 ～ 1990)
Year
De
ath
Ra
te (
De
ad/
Po
pula
tion
)
3. Challenges
1. Asian cities in low-lying deltas will be increasingly at risk. - Impacts of climate change and SLR - Large population growth and development
2. Development policies and city management aim mainly at short-term goals. - Today’s problems - Large portion of today’s investments will be affected by CC/SLR i.e. 10 to 50% of investment to infrastructure such as coastal dikes, loads, bridges, irrigation facilities.
3. How to incorporate the future risk of CC/SLR into today’s management. - Role of adaptation: increase the preparedness with solving today’s problems - Win-Win approach both to present and future problems - Mainstreaming adaptation
4. Major target of adaptation for coastal cities is management of growth. - Impact and vulnerability assessment is the first step. - Regulate migration of population - Incorporate adaptation to CC in to infrastructure construction and city planning
Thank you very much!