CLIMATE CHANGE AND HEALTH:

HEAT: PHYSIOLOGICAL LIMIT

AND IMPACT ON HEALTH

Norlen Mohamed

Melaka, 18 April 2018

Outline of presentation

Physiology of heat loss & gain

Impact on health

Hot Weather, observed and projected

Risk factors for heat related

illness

Weather = current state of the

atmosphere (T, humidity, rainfall, wind, cloud etc )

Climate = long term average of weather > 10 years

Cuaca Panas

Kategori Definisi

Hari yang panas

(Hot day)

Mana-mana hari yang merekodkan suhu maksimum

antara 35°C hingga 37°C.

Nota: Purata jangka panjang suhu maksimum di

Malaysia (30°C hingga > 34°C, tetapi tidak melebihi

35°C)

Hari yang sangat

panas

(Very hot day)

Mana-mana hari yang merekodkan suhu maksimum

melebihi 37°C

Gelombang haba

(Heatwave)

(i) Suhu tertinggi harian (atau suhu maksimum) sesuatu

tempat yang mencapai 35°C untuk 5 hari berturut-

turut dan juga melebihi 2°C daripada purata jangka

panjang suhu maksimum; atau

(ii) Suhu tertinggi harian yang mencapai atau melebihi

37°C untuk tempoh 3 hari berturut-turut di sesuatu

tempat

Tahap Amaran

Tahap Status Suhu

Tiada Amaran

(0)

- Suhu di bawah 35 0C

Amaran

Pertama (1)

Berjaga - jaga

(Amaran Gelombang

Haba)

Suhu tertinggi harian melebihi 35 0C hingga

37 0C selama tiga hari berturut-turut

Amaran kedua

(2)

Gelombang Haba Suhu tertinggi melebihi 37 0C untuk tiga hari

berturut-turut – pengistiharan “heatvave”

oleh MOSTI

Amaran Ketiga

(3): Kecemasan/

Bencana

Kecemasan

Gelombang Haba

Suhu tertinggi harian melebihi 40 0C untuk 3

hari berturut-turut – Pemakluman kepada

Agensi Pengurusan Bencana Negara

(NADMA) bagi pengistiharan kecemasan

(Sumber: JK Teknikal Pelan Tindakan Gelombang Haba Kebangsaan, Jabatan Alam Sekitar)

Equinox – Menyebabkan cuaca panas

melampau? • Sering kali diviralkan

• Salah faham

• Apa itu Equinox?

• Fenomena Astronomi

Source of picture: https://sitel.com.mk/shto-znachi-proletnata-ramnodenica

Climate phenomenon – El Nino

• Fenomena Iklim

• Diukur – Nino index

Sejarah El Nino

https://climatedataguide.ucar.edu/climate-data/nino-sst-indices-nino-12-3-34-4-oni-and-tni

Suhu Ambien meningkat semasa El Nino

http://notrickszone.com/2016/07/19/el-nino-2016-now-history-la-nina-coming-the-earth-is-

cooling/#sthash.KZ960MEN.dpbs

With Climate change

• Increase global warming

• Worsen the El Nino effects

With climate change

Jan 2005

Jan 2016

Jan 1990

Jan 2017

Sept 1984

Sept 2016

0.17°C/10years 0.13°C/10years

0.23°C/10years

Mean Temperature Trend

Slide Courtesy: Yap Kok Seng, UNU Seminar , May 2017

Perubahan Iklim di Malaysia

Observed climate change

Malaysia World

Climate

parameter

s

Peninsul

ar (1969-

2009)

Sarawak

(1969-

2009)

Sabah

(1969-

2009)

1901-2012

Temperature 1.1 oC 0.6 oC 1.2 oC0.89 oC (0.69-1.08

oC)

Sea level rise 2.73-7.00 mm/yr (1993-2010)

190 mm (170-210 mm)

(1901-2010) or

1.5-1.9 mm/yr

Source : Shaaban A.J. (2014). Climate change adaptation and its impact :

Presentation of water sector. IDFR-Unam Workshop on Malaysia’s climate

change strategies : Plan of action, Kuala Lumpur, 10 September 2014.

Projected Temperature

• Climate Change already observed in Malaysia

• Projected temperature changes ranged from 1-2 oC by

2050 and up to 3 oC by 2100

• Rainfall changes is around 5-10 % by 2050

• Sea level projected to increase by 0.6 – 1 m by 2100

• Adaptation to climate changes need to be mainstreamed

into development

Slide Courtesy: Yap Kok Seng, UNU Seminar , May 2017

WBGTmax

1995

2085

2200

With climate changethe world become

hotter. More frequent

and severe heat wave is

projected

More heat related morbidity &

mortality

Reduce health-based

socioeconomic productivity

If no mitigation and adaptation,

this what is predicted to happen

• ADAKAH KITA DI NEGARA BERCUACA PANAS

VULNERABLE?

• ATAU KITA SUDAH IMMUNE DENGAN CUACA PANAS?

Physiology of heat gain and loss

• Perlu difahami

How much heat we produce?

If there is no heat loss from the

body, what will happen to core T?

Work intensity in different activities

Activity

(potential levels in jobs shown)

Work intensity

(W/m2)

Sitting quietly 58

Standing 70

Walking slowly 116

Assembly work, walking (shoe factory) 174

Carpentry 203

Raking leaves, walking fast (harbour work) 232

Mowing lawn, power mower (lead smelter) 261

Chopping wood (sugar cane cutting) 348

Shovelling, digging trenches (gravel crushing) 493

Normal Distribution of body T

What happen if Ambient T > Body T

HEAT ACCLIMATIZATION

• 9o min daily

• heat-exercise exposure

• The thermoregulatory

benefits from heat

acclimatization are generally

complete by 10-14 d of

exposure

Heat Stress Illness

Heat related illness

0

5

10

15

20

25

30

35

1-M

ar-

16

3-M

ar-

16

5-M

ar-

16

7-M

ar-

16

9-M

ar-

16

11-M

ar-

16

13-M

ar-

16

15-M

ar-

16

17-M

ar-

16

19-M

ar-

16

21-M

ar-

16

23-M

ar-

16

25-M

ar-

16

27-M

ar-

16

29-M

ar-

16

31-M

ar-

16

2-A

pr-

16

4-A

pr-

16

6-A

pr-

16

8-A

pr-

16

10-A

pr-

16

12-A

pr-

16

14-A

pr-

16

16-A

pr-

16

18-A

pr-

16

20-A

pr-

16

22-A

pr-

16

24-A

pr-

16

26-A

pr-

16

28-A

pr-

16

30-A

pr-

16

2-M

ay-1

6

4-M

ay-1

6

6-M

ay-1

6

8-M

ay-1

6

Heat related illness reported from Goverment Health Facilities, 1 Mac- 19 April 2016

Total (H.Cramp) Total (H. Exhaustion) Total (H. Stroke) TOTAL

Mortality and temperature during the 2009 Melbourne heatwave

Relationship between ambient

temperature and NCD YLL, Burkina Faso

Slide courtesy Aditi Bunker, Network Aging Research and Institute of Public Health

Heidelberg University

Ringkasan golongan berisikoKumpulan Berisiko

Warga emas berumur 65 tahun ke atas

Bayi dan kanak-kanak di bawah umur 5 tahun

Ibu hamil atau menyusukan bayi

Golongan dengan NCD, Obesity

Kumpulan pekerja yang terdedah secara langsung dangan cuaca panas

Individu yang melakukan aktiviti fizikal semasa cuaca panas

Golongan yang kurang minum air (tahap hydrasi badan rendah)

Pendatang atau populasi sementara seperti pelancong

Pengetahuan terhad mengenai sistem amaran setempat, program

kesihatan dan perkhidmatan sosial

Heat and Work Rest Ratio

Work ability (%) as a function of WBGT (degr.C)

at 4 work intensities (Watts), acclimatized

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

20 25 30 35 40

Temperature C

Wo

rk A

bilit

y % 500 Watts

400 Watts

300 Watts

200 Watts

ISO-based WRRs (Work Rest Ratio) or

ISO recommended maximum work-rest ratio (WRR) during

an hour of work in hot environments

Work intensity, Watts

WBGT

heat stress

index level

25 % work

100 % work

Melaka

Work ability (%) as a function of WBGT (degr.C)

at 4 work intensities (Watts), acclimatized

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

20 25 30 35 40

Temperature C

Wo

rk A

bilit

y % 500 Watts

400 Watts

300 Watts

200 Watts

Alor Setar & KangarWork ability (%) as a function of WBGT (degr.C)

at 4 work intensities (Watts), acclimatized

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

20 25 30 35 40

Temperature C

Wo

rk A

bilit

y % 500 Watts

400 Watts

300 Watts

200 Watts

KLWork ability (%) as a function of WBGT (degr.C)

at 4 work intensities (Watts), acclimatized

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

20 25 30 35 40

Temperature C

Wo

rk A

bilit

y % 500 Watts

400 Watts

300 Watts

200 Watts

C.HighlandWork ability (%) as a function of WBGT (degr.C)

at 4 work intensities (Watts), acclimatized

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

20 25 30 35 40

Temperature C

Wo

rk A

bilit

y % 500 Watts

400 Watts

300 Watts

200 Watts

Take home message

• Increase in temperature is the most certain effects of

climate change

• Physiological adaptation has limit, need to increase

behavioural and environmental adaptation

• Physical activities is critical during hot weather

• Effect are not equal due to vulnerability status / risk

factors

• During heatwave

• loss of heat through evaporation

• adequate water intake is critical

• Avoid physical activity

• Find a cooler environment