+ All Categories
Home > Documents > Future coastal flooding scenarios for the world's largest mega …...Future coastal flooding...

Future coastal flooding scenarios for the world's largest mega …...Future coastal flooding...

Date post: 25-Jan-2021
Category:
Upload: others
View: 1 times
Download: 0 times
Share this document with a friend
19
Future coastal flooding scenarios for the world's largest mega-city M. De Dominicis, J. Wolf, S. Jevrejeva, P. Zheng Z. Hu 10th UK FVCOM users’ workshop 27th - 28th November 2019, Liverpool
Transcript
  • Future coastal flooding scenarios for the world's largest mega-city

    M. De Dominicis, J. Wolf, S. Jevrejeva, P. ZhengZ. Hu

    10th UK FVCOM users’ workshop 27th - 28th November 2019, Liverpool

  • • The Pearl River Delta in the South China Sea is densely populated, fast-developing, and the most

    urbanised delta in the world. As it is very low-lying, cities here, like Guangzhou, are the most vulnerable to

    sea level rise.

    • ANCODE aims to better understand the potential for re-introducing nature-based coastal defences, namely

    mangroves and oyster reefs, into such environment.

    Applying Nature-based COastal DEfence

    in the Pearl River Delta: the ANCODE projectfunded by EPSRC under the NEWTON programme “Sustainable Deltas”

    In collaboration with Sun Yat-Sen university (China) and NIOZ (Netherlands)

  • National Oceanography Centre

    Sea level rise by 2100

    The changes in regional sea level are quantified in this

    work by using probabilistic regional sea level

    projections for selected scenarios of climate change. SEA LEVEL EXPANSION GLACIERS GREENLAND ANTARCTICA LAND WATER

    Jevrejeva et al, 2016

    GUANGZHOU SHENZEN

    99th

    95th

    50th

    99th

    95th

    50th

    PROJECTION IN CHINA

    GLOBAL PROJECTION

    RCP8.5 RCP8.5

    95th

    50th

  • National Oceanography Centre

    An FVCOM (Finite Volume Community Model) implementation for the South China

    Sea and Pearl River Delta is used to understand how the rising mean sea level, tides

    and storm surge can interact and affect coastal inundation in the Pearl River Delta.

    Modelling the Pearl River Delta

    Details…

    - FVCOM 4.0

    - 25 vertical sigma layer, uniform

    - Tides: TPXO8.0, 13 components

    M2,S2,N2,K2,K1,O1,P1,Q1,MF,MM,M4,MS4,MN4

    - Bottom friction: uniform roughness length (0.001 m)

    with minimum Cd=0.0025

    - Grid: 85129 nodes - 140449 elements

    - Time step: 0.1/0.2 s external mode (barotropic)/0.5/0.10

    s internal mode (baroclinic)

    - River discharge: annual/seasonal averages

  • National Oceanography Centre

    Validation

    4 Tide Gauges available with hourly resolution from U Hawaii Sea Level Centre:

    Hong Kong 1962-01-01:2016-12-30

    Macau 1978-01-01:1985-05-30

    Zhapo 1975-01-01:1997-12-30

    Shanwei 1975-01-01:1997-12-31

  • National Oceanography Centre

    Validation

  • Changes in tides for wet and dry seasons under

    4 different future sea level scenarios: 0.3m, 0.5m, 0.9m and 2.1m

    (i.e. the 50th and 95th percentile for 2050 and 2100).

    Changes in surge for the 2 latest and strongest typhoons hitting the PRD under

    the same 4 future sea level scenarios.

  • CH

    AN

    GE

    SIN

    M

    SL

  • CH

    AN

    GE

    SIN

    T

    IDE

    S2(M2+S2)

    M2+O1+K1

  • Storm tracks

    International Best Track Archive for Climate Stewardship (IBTrACS) - NOAA

  • Typhoon Hato

    August 2017

    ERA5 reanalysis

  • Typhoon Hato

    August 2017

    Holland’s windsCH

    AN

    GE

    S

    INS

    UR

    GE

  • CH

    AN

    GE

    S

    INS

    UR

    GE

    Typhoon Mangkhut

    September 2018

    Holland’s winds

  • • In a delta environment, sea level rise is not simply added to extreme water levels, but

    introduces feedbacks on tides and surge levels

    • Amplification of tides could exceed 0.5 m for 2.1 sea level rise and should be

    considered when planning future coastal defences.

    • Sea level rise can induce a reduction of surge level of up to 0.5 m ins ome coastal areas

    for typhoons like Hato or Mangkhut

    Conclusions & Future plans

  • Conclusions & Future plans

    • Our final aim is to use the Pear River Delta FVCOM model to optimise the location of

    mangroves spaces for defence, under contrasting scenarios of climate change.

    • This requires (ideally):

    • Wave-current-sediment coupled models (FVCOM)

    • Vegetation Model (to be introduced in FVCOM)

  • Making Sense of Changing Seas

    Thank you

    @[email protected]


Recommended