Smart Cities and Environmental Change

PETER BRIMBLECOMBE School of Energy and Environment City University of Hong Kong

ENVIRONMENTAL CHANGE Climate - temperature Climate - water

Air pollution

Subtlety of the change

Validity of high-tech or heavy engineering solutions

HEAT DEATH

Forzieri et al.(2017) Increasing risk over time of weather... The Lancet Planetary Health, e200 - e208

2700 annual heat-related fatalities in Europe projected grow ~150000 by 2071-00

Results "could be overestimated” South Korea's Seoul National University

8 DAYS IN PARIS (Aug 2003) T>30o C

14,802 heat-related deaths>30

Health Minister Mattei criticized and shuffled out of ministry

Families and GPs vacationing

Weakest individuals had fewer deaths - in care

8 DAYS IN HONG KONG (Jun 2016) T>30o C

DEFINING A HEAT WAVE

Measured relative to usual weather

People from hotter climates consider normal a heat wave in cooler areas (sociological)

However some modellers assume a threshold (physiological) Robinson, Peter J. (April 2001). "On the Definition of a Heat Wave". Journal of

Applied Meteorology. American Meteorological Society. 40 (4): 762–775.

IT’S NOT THE HEAT IT’S THE HUMIDITY!

However, it is about wet bulb rather than dry bulb temperatures.

At 46 °C and RH 50% the wet-bulb T would be 35 °C

Core ~37°C

Skin <35 °C

cotton, is pervious to sweat, but impervious to radiant heat

HEAT- ADAPTABLE HUMIDITY- PHYSIOLOGICAL LIMIT

Eun-Soon et al (2017) Deadly heat waves projected in the densely populated agricultural regions of South Asia Science Advances

Europe may adapt to hot weather India may be at the physiological limit

HIGH WET BULB TEMPERATURES

WHY SO SERIOUS ON INDIAN SUBCONTINENT?

Monsoon system transports warm and humid air masses into the Indus and Ganges valleys

Elevations <100 m so surface air generally warmer than surrounding areas

Valleys irrigated, enhancing water content via modifications to surface energy balance

WETBULB TEMPERATURES LIMIT TO SURVIVABILITY

Urban heat islands can enhance temperatures, but lack of vegetation lowers RH

Risk to agricultural workers

TECHNOLOGICAL FIX

Issue of poverty France criticised for

not building in air conditioning

Is it the solution?

Let them install air conditioning

SMART SOLUTIONS Air conditioning

Often argued as a solution, but problems Tw>35o – need dehumidification

Architecture Massive overhanging roofs

Inset windows Heavy mass Minimal surface area Ventillated

PRECIPITATION CHANGE WATER SUPPLY

Clean Drinking water is limited, global warming adds pressure to security of HK supply

1963, Hong Kong citizens queuing

for water

David van Eiff (PhD SEE) An Optimal Water Mix for Hong Kong

http://www.hko.gov.hk/prtver/html/docs/hko_virtualtour/vtour/vtour_e/details/p8_1.shtml

LANDSLIDES General view that more

rain means more landslides.

Challenged “landslide frequency in many humid landscapes may be insensitive to projected changes in the frequency of intense rainfall events”

Parker et al (2016) Colluvium supply in humid regions limits the frequency of storm-triggered landslides Scientific Reports 6, 34438

LANDSLIDES Hong Kong Slope

Safety System is well regarded

Changes may be driven more by maintenance

http://www.cedd.gov.hk/eng/achievements/geotechnical/safety_system/index.html

INCREASED URBAN RUN OFF

Hamdi et al (2011) Effects of urbanization and climate change on surface runoff of the Brussels Capital Region, Int. J. Climatol

Urban fabric or climate change

Maintenance!

DRIVEN BY HARD SURFACES URBAN SURFACES

SMART Tunnel Kuala Lumpur–

Expressway Stormwater Management and Road Tunnel

2011: SMART tunnel received the UN Habitat Scroll of Honour Award

SOAKWAYS

Softer surfaces as part of street sign

Designs - smart and active

VARIABLE URBAN LAND USE

SOIL MOISTURE CHANGE CHANGE IN ANNUAL MEAN SOIL MOISTURE (UPPER 10 cm)

2081–2100

OLD PARADIGMS BREAK DOWN

EMISSIONS

CONCENTRATIONS

EXPOSURE

HEALTH

These may not follow a nice linearity

SEPTEMBER 1986 REMOVE LEAD

EMISSIONS ≠ CONCENTRATION SECONDARY POLLUTANTS- PHOTOCHEMICAL SMOG

EXPOSURE PARADIGM

Emissions and over concentrations may not relate to exposure

At home/in transit/in shops/waiting for a bus

Varied activities mean that: CONCENTRATION OUTDOORS ≠ EXPOSURE

Home may be

important!

CONCENTRATION ≠ EXPOSURE

HEALTH OUTCOME ≠ CONCENTRATION

0

1

2

3

4

5

6

Mobile Coal Crustal

% D

aily

mor

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Laden et al Association of fine particulate matter from different sources with daily mortality in six U.S. cities Environmental Health Perspectives 108, 941-947( 2000)

Impact of 10 μg/m3 increase in PM2.5 from various sources

e.g. particle size or composition may drive health outcomes

AIR QUALITY MANAGEMENT TO REVERSE DIRECTION

EMISSIONS

CONCENTRATIONS

EXPOSURE

HEALTH Requires going beyond emission reduction, rather encourage social changes

NOT SMART

BUS IS BANNED!

http://www.bbc.com/news/science-environment-40826648

http://www.bbc.com/news/world-asia-china-40492697

Restructuring cities

Changing transport

Walkability Urban green

spaces

CONCLUSIONS SMARTNESS MAY INVOLVE RECOGNISING 1 subtlety of environmental change 2 potential of sociological and soft fixes 3 appropriate technology/engineering

THE END