Impacts of a future city master plan on on thermal and wind environments in Vinh city, Vietnam

Transcription

1 Impacts of a future city master plan on on thermal and wind environments in Vinh city, Vietnam Satoru Iizuka, Nagoya University, Japan Tatsunori Ito, Nagoya University, Japan Masato Miyata, Mitsubishi UFJ R&C, Japan

2 Background: Vietnam's recent growth [%] Economic growth rate ベトナムの 経 済 成 長 率 Average: 6% [ 000] ベトナムの 人 口 増 加 の 割 合 Population Growth rate:.2% Source: IMF-World Economic Outlook Databases Source: The World Bank Under the situation of Vietnam's recent growth, many city master plans have been proposed. 2

3 City master plan for Vinh city, Vietnam By Nikken Sekkei Civil Engineering Ltd., Japan Target period : 2030 Planned population : 900,000 3

4 Population 450,000 Land Area 05 km 2 Vinh city, Vietnam () N Vinh city Hanoi Ho Chi Minh 4

5 Vinh city, Vietnam (2) Air temperature [ ] Air temperature of Vinh Air temperature of Tokyo Precipitation [mm] In Vinh city, June is the hottest month. Sep. and Oct. are rainy months. 5

6 Introduction of city master plan CBD (Central Business District) Dryland Cropland and Pasture Cropland/Woodland Mosaic Deciduous Broadleaf Forest Existing Urban District Irrigated Cropland and Pasture Grassland Water Bodies New Urban District Cropland/Grassland Mosaic Shrubland Present land use City master plan (2030; 900,000 people) 6

7 Development of downscaling model Global scale Regional scale Urban scale Nagoya Building scale GCM + WRF + LES downscaling Ise Bay 7

8 Computational domains and grid design Domain Domain 3 Vietnam 52.5 km Laos Domain 2 South China Sea City master plan area 46.5 km Size Grid points Horizontal grid Domain 585 km 540 km 2 km km Domain 2 77 km 59 km 2 km km Domain km 46.5 km 2 km km 8

9 Simulated cases () Period Land use Case 0 June in 20 (Present) Present land use Case Case 2 Case 3 Case 4 June in the 2030s (Future) Present land use City master plan Northern concentration of the new urban districts Southern concentration of the new urban districts Three categories in the urban area:. Central business district (CBD) Average height of buildings: 26 m, Building (green) coverage ratio: 50% (50%) 2. Existing urban district Average height of buildings: 2 m, Building (green) coverage ratio: 70% (30%) 3. New urban district Average height of buildings: 2 m, Building (green) coverage ratio: 70% (30%) 9

10 Simulated cases (2) Present land use (Cases 0 and ) Master plan (Case 2) Northern concentration (Case 3) Southern concentration (Case 4) 0

11 Future projection by pseudo global warming method General circulation model: GFDL-CM3 Pseudo global warming data based on RCP 8.5 scenario Initial and boundary conditions for WRF simulations Domain Domain 3 Vietnam Laos Domain 2 South China Sea 52.5 km 46.5 km

12 Effect of global warming in the 2030s Future (the 2030s) climate with present land use (Case ) Present (20) climate with present land use (Case 0) Temperature difference [ C] Space- and monthly-averaged diurnal variation of the difference in air temperature (at 2 m) Time [h].76 Present land use 2

13 Effect of introducing city master plan Future (the 2030s) climate with city master plan (Case 2) Future (the 2030s) climate with present land use (Case ) Temperature difference [ C] Space- and monthly-averaged diurnal variation of the difference in air temperature (at 2 m) ( ) City master plan 0.7 Present land use Source: IPCC Fifth Assessment Report, Synthesis Report (SPM) Time [h] 3

14 Effect of new urban district structure () Future (the 2030s) climate with modified master plan (Case 3) Future (the 2030s) climate with city master plan (Case 2) Temperature difference [ C] Space- and monthly-averaged diurnal variations of the difference in air temperature (at 2 m) CBD New urban (North) Existing urban City master plan Northern concentration Time [h] 4

15 Effect of new urban district structure (2) Future (the 2030s) climate with modified master plan (Case 4) Future (the 2030s) climate with city master plan (Case 2) Temperature difference [ C] Space- and monthly-averaged diurnal variations of the difference in air temperature (at 2 m) CBD New urban (South) Existing urban City master plan Southern concentration Time [h] 5

16 Summary. With the continuous progress of global warming, the future (the 2030s) thermal environment in Vinh city was about.8 hotter than that in the present status. 2. By introducing the proposed city master plan, the averaged air temperature in the urban areas was 0.7 higher than that in the case with the present land use. 3. The future (the 2030s) thermal environment in the case with the original city master plan was better than that with the northern or southern concentration of the new urban districts. 6

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18 RCP scenarios IPCC 5th assessment report RCP: Representative Concentration Pathway Source: IPCC AR5 Working Group I Summary for Policymakers 8

19 Pseudo global warming data () Components of global warming. Horizontal wind components 2. Potential temperature 3. Geopotential height 4. Sea surface temperature 5. Ground surface temperature 9

20 Pseudo global warming data (2) ) Monthly variations of 0-year averaged data from 2030 to 2039 based on the RCP 8.5 scenario 2) Monthly variations of 0-year averaged data from 2000 to 2009 ) 2) was added to the present (June 20) NCEP Final Operational Global Analysis data. 20