quantifying the stability of summer temperatures for different thermal climate zones: an application...

1

Quantifying the Stability of Summer Temperatures

for Different Thermal Climate Zones: An Application

to the Bangkok Metropolitan Area

Manat Srivanit Faculty of Architecture and Planning, Thammasat University (Rangsit Campus), Thailand E-mail address: [email protected]

November 28, 2013

1.INTRODUCTION

2

Most researchers agree on the fact that, the impact of climate in the urban

planning process in practice is usually low [Oke, 1984; Lindqvist and

Mattsson, 1989; Pressman, 1996].

Urban Climatology Urban Planning

Science / Theoretical

Climatologist

Multi-scale phenomena

Observational approaches;

Field measurement,

Thermal remote sensing,

Small-scale modeling at

the canopy level

Applied

Engineer/Artistic/Planner

Different urban scales

decisions

Outdoor environment

Urban forms & functions

Comfort & health

Landscape planning

The goal of creating more

sustainable settlements

Focus on achieving

predictive power

[Source: Author]

Needed to Develop Tools and Systems Suitable

for Urban Planners

Climate

knowledge have

low impact on

the planning

process

The Six Basic Factors determining thermal comfort

These factors may be independent of each other, but together contribute to a

worker’s thermal comfort. The most commonly used indicator of thermal comfort

is air temperature, it is easy to use and most people can relate to it.

(HSE http://www.hse.gov.uk)

4 Environmental factors

2 Personal factors

What is Comfort or Discomfort for Human?

http://www.hse.gov.uk/

4

Fig. A Schematic Representation of the Many Functions and Disciplines Essential for

Effective Urban Climate Adaptation [Source: Modified from Chee F.C. et al., 2007]

Urban climate and urban planning responses

“Transferring scientific

research into tools

applicable for urban

planning ought to be a

great challenge for urban

climatologists.”

URBAN

CLIMATIC

ASSESSMENT

PHYSICAL AND SOCIAL

SCIENCESURBAN PLANNING

HEALTH SCIENCES

ANALYSIS OF

SOCIO-ECONOMIC CONDITIONS

MESUREMENT AND

MODELING OF URBAN CLIMATIC

EPIDEMIOLOGICAL STUDIES

ASSESSMENT OF

URBAN FORM AND

PHYSICAL CONDITIONS

STAKEHOLDER

ENGAGEMENT AND PUBLIC PARTICIPATION

HEALTH CRISIS ALERT

AND RESPONSE SYSTEMS

ADAPTATION STRATEGIES

HEALTHY, WELL

ADAPTED COMMUNITIES

EVALUATION

OF

ADAPTATION

STRATEGIES

v

Urban Climate and Environment

(Urban Heat Island-UHI)

Geographic Location

Time

Synoptic WeatherClimate

Topography

rural surrounds

•Day

•Season

•Cloud

•Wind

City Size

Linked to form

and function

City Function•energy use

•water use

•pollution

•Materials

•Geometry

•Green space

City Form

Limits UHI, for

simplicity we’ll

assume ideal calm,

clear, i.e. ‘worst

case’

Of potential use in

mitigation

Factors controlling urban climate

International Conference on Southeast Asian Weather and Climate 2013 “ASEAN Adapting to Climate Change”

5

Modified from Oke, 2006

6

Climatic changes induced by settlements in the Asia cities

Figs. (a) Percentage of Population Residing in Urban Areas by Continent 1950-

2050 and (b) Variation in Yearly Mean Temperature in Large Asian Cities Using

Observational Temperature Data.

Year

b

Tem

pera

ture

( C

)

a

Perc

en

tag

e o

f p

op

ula

tio

n r

esi

din

g i

n u

rban

are

as

Year

Africa

Asia

Europe

Latin America

& the Caribbean

North America

Oceania

Source: United Nations, 2010 Source: Kataoka et al., 2009

Fig. Urbanization and Changes of Settlement Patterns in Bangkok Metropolitan

since 1900 to 1981 (source: Sternstein, 1982)

Problematic Urban Climate Aspects in Hot-humid Summer Climate of Bangkok

7

Land use/cover patterns and changes in Bangkok city

LULC Types Year Changes

1994 2000 2009 1994-2009

Built-up area 233.33 (14.80%)

519.87 (32.98%)

657.29 (41.70%)

423.96 (26.90%)

Vegetated area 1,131.08 (71.76%)

777.52 (49.33%)

636.01 (40.35%)

-495.07 (-31.41%)

Water bodies 177.69 (11.27%)

207.36 (13.16%)

167.95 (10.66%)

-9.73 (-0.62%)

Other (bare land)

34.00 (2.16%)

71.36 (4.53%)

114.84 (7.29%)

80.84 (5.13%)

Table:

Land use/cover statistics (area in sq.km, percentage

of the total study area) in Bangkok

Agricultural land was converted to urban

uses as Bangkok expanded along three

major transport corridors to the southwest,

southeast and north of the city.

The expansion of urban land use is

characterized by unplanned, sprawl and

ineffectively regulated.

Source: Srivanit, M. and Hokao, K., 2012 8

Fig.5.2 The Bangkok city’s Evaluation (Boonwong, 2006)

(2) Changing Urban Form in Bangkok

9

Fig. Schematic of climatic scales and vertical layers found in urban areas

Source: modified from Tim Oke (1997)

1.Urban Boundary Layer (UBL)

2.Urban

Canopy Layer

(UCL)

10

Scale and layers relevant to urban climate

Urban Surface/ Near-surface

Temperature

Climatic conditions and the impacts of hot-humid tropical climatic of Bangkok

11

Average seasonal pattern of daily mortality

Total electricity consumption by sectors Electricity consumption pattern

Urban climatic characteristic


2.) This study aims:

To construct a thermal climate zones (TCZs)

classification system, which is defined as an area of

thermally homogenous surface morphological

properties.

To assess the stability of summer temperatures for

different TCZs, and quantify the relationship

between regional land surface temperature (LST)

variations and the TCZ morphological features.

International Conference on Southeast Asian Weather and Climate 2013 “ASEAN Adapting to Climate Change” 12

3.) Schematic presentation of thermal climate zones classification methodology

LANDSAT TM

Satellite images

Acquired on April

25, 2009

Thermal Infrared

Band (10.4–12.5 m)

or Band 6

Conversion of digital

numbers to radiation

radiance value

Land surface

temperature (LST)

Radiometric and

Geometric correction

(i) Green coverage

ratio (GCR)

Spectral reflectance

in TM red (band3)

and near-infrared

(band4)

Quantifying the stability of summer temperatures for different thermal climate

zones (Spearman’s rank correlation to examine the relationship)

GIS Vector Data

Scale 1:4,000

Building layers were

taken in 2009

Derivation of Surface Morphological Parameters (Spatial grid cells with a size of 300 m.)

Calculation of surface

configuration parameters

13

Calculate the normalized

difference vegetation

index (NDVI)

(ii) Building coverage

ratio (BCR)

(iii) Floor area ratio

(FAR)

A GIS-Multivariate Analysis Approach to Delineate

Thermal Climate Zones (TCZs) : Cluster Analysis (CA)

Spatial Character Differentiation

of TCZ Classes

Va

lid

ati

on

Da

ta

14

(a.) Surface composition [proportion of ground plan covered by impervious cover]

(a)

(b)

Spatial variability of building and exposed ground coverage ratio (BCR)

Where: T

IR

T

C

A

AA

A

ABCR

is building and exposed ground coverage ratio (%),

is the combined surface area of the buildings and exposed ground,

is the building roof area,

is the area of impervious surface at ground level, and

is the plan area of the study site

BCRCA

RA

IA

TA


(b.) Surface configuration [dimensions of the buildings roughness]

15

Spatial variability of floor area ratio (FAR) distributed according to a uniform grid mesh

T

N

i

if

A

hA

FARi

1

is floor area ratio (unitless values),

is the area of the building footprint at ground level,

is the height of building ,

is the total number of buildings in the plan area fraction,

is the total plan area of the region of interest

FAR

fiA

ihi

i

N

TA

Where:


16

(c.) Surface composition [proportion of ground plan covered by vegetated area]

(a)

(b)

Spatial variability of green coverage ratio (GCR)

Where: T

BGAG

T

G

A

AA

A

AGCR

is green and pervious surface coverage ratio (%),

is the combined surface area of the horizontal green cover,

is the trees canopy areas (or above green cover),

is the summation of grass, shrubs, cultivated plants and pervious

surface at ground level, and

is the plan area of the study site

GCR

GA

AGA

BGA

TA

Distribution of Green Coverage Ratio in BMA


Schemes of BMA’s TCZs

in 7 classes include:

nearest zones

farness zones

(i)Nearest zone

(ii)Farness zone

The mean class centroid

Class membership

(zones)

(a)

(b)

Dis

tance o

f zone f

rom

cla

ss c

entr

oid

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

1.00

0 1 2 3 4 5 6 7 8

Class membership

Farness cases

Nearest cases

17

Dusit

Bangphlat

Sathon

Bangkok Noi

Phayathai

Thonburi

Din Dang

Pathumwan

Ratthewee

Khlong San

Bangkok Yai

Bang Rak

Phra

Nakhorn

Pom Prap

Sattru Phai

Samphanthawong

1

4

3

ø÷3242

ôó35

ø÷338

ø÷304

ø÷304

7

Nong Chok

Latkrabang

Minburi

Prawet

Bang Khun Thian

Khlong Sam Wa

Sai M ai

Bang Khae

Bang Khen

Lak Si

Bang Bon

Nongkham

Don Muang

Thung Kru

Chatuchak

Bangkapi

Taling ChanThawee Wattana

Bungkum

Kanna Yao

Dusit

Bang Na

Lat Phrao

Saphan Sung

Suan Luang

Chom ThongYannawa

Watthana

Bang Sue

Phasi Charoen

Huai Khwang

Ratburana

Bangphlat

Khlong ToeiSathon

Bangkok Noi

Wang Thong LangPhayathai

Phra Khanong

Thonburi

Din Dang

Pathumwan

Ratthewee

Bangkho Laem

Khlong San

Bangkok Yai

Bang Rak

Phra

Nakhorn

Pom Prap

Sattru Phai

Samphanthawong

5 0 5

Kilometers

2 0 2 4 Kilometers

Floor Area Ratio (F.A.R.)

Note: Grid size 500X500 meters

Less than 0.10.1 - 0.20.2 - 0.30.3 - 0.40.4 - 0.5

0.5 - 0.60.6 - 0.70.7 - 0.80.8 - 0.90.9 - 1.0

None building

Dusit

Bangphlat

Sathon

Bangkok Noi

Phayathai

Thonburi

Din Dang

Pathumwan

Ratthewee

Khlong San

Bangkok Yai

Bang Rak

Phra

Nakhorn

Pom Prap

Sattru Phai

Samphanthawong

1

4

3

ø÷3242

ôó35

ø÷338

ø÷304

ø÷304

7

Nong Chok

Latkrabang

Minburi

Prawet

Bang Khun Thian

Khlong Sam Wa

Sai M ai

Bang Khae

Bang Khen

Lak Si

Bang Bon

Nongkham

Don Muang

Thung Kru

Chatuchak

Bangkapi


Bungkum

Kanna Yao

Dusit

Bang Na

Lat Phrao

Saphan Sung

Suan Luang

Chom ThongYannawa

Watthana

Bang Sue

Phasi Charoen

Huai Khwang

Ratburana

Bangphlat

Khlong ToeiSathon

Bangkok Noi


Phra Khanong

Thonburi

Din Dang

Pathumwan

Ratthewee

Bangkho Laem

Khlong San

Bangkok Yai

Bang Rak

Phra

Nakhorn

Pom Prap

Sattru Phai

Samphanthawong

5 0 5

Kilometers

2 0 2 4 Kilometers

Building Coverage Ratio (BCR)


Less than 0.10.1 - 0.20.2 - 0.30.3 - 0.40.4 - 0.5

0.5 - 0.60.6 - 0.70.7 - 0.80.8 - 0.90.9 - 1.0

None building

Dusit

Bangphlat

Sathon

Bangkok Noi

Phayathai

Thonburi

Din Dang

Pathumwan

Ratthewee

Khlong San

Bangkok Yai

Bang Rak

Phra

Nakhorn

Pom Prap

Sattru Phai

Samphanthawong

1

4

3

ø÷3242

ôó35

ø÷338

ø÷304

ø÷304

7

Nong Chok

Latkrabang

Minburi

Prawet

Bang Khun Thian

Khlong Sam Wa

Sai M ai

Bang Khae

Bang Khen

Lak Si

Bang Bon

Nongkham

Don Muang

Thung Kru

Chatuchak

Bangkapi


Bungkum

Kanna Yao

Dusit

Bang Na

Lat Phrao

Saphan Sung

Suan Luang

Chom ThongYannawa

Watthana

Bang Sue

Phasi Charoen

Huai Khwang

Ratburana

Bangphlat

Khlong ToeiSathon

Bangkok Noi


Phra Khanong

Thonburi

Din Dang

Pathumwan

Ratthewee

Bangkho Laem

Khlong San

Bangkok Yai

Bang Rak

Phra

Nakhorn

Pom Prap

Sattru Phai

Samphanthawong

5 0 5

Kilometers

2 0 2 4 Kilometers

Green Coverage Ratio (GCR)


Less than 0.10.1 - 0.20.2 - 0.30.3 - 0.40.4 - 0.5

0.5 - 0.60.6 - 0.70.7 - 0.80.8 - 0.90.9 - 1.0

Dusit

Bangphlat

Sathon

Bangkok Noi

Phayathai

Thonburi

Din Dang

Pathumwan

Ratthewee

Khlong San

Bangkok Yai

Bang Rak

Phra

Nakhorn

Pom Prap

Sattru Phai

Samphanthawong

1

4

3

ø÷3242

ôó35

ø÷338

ø÷304

ø÷304

7

Nong Chok

Latkrabang

Minburi

Prawet

Bang Khun Thian

Khlong Sam Wa

Sai M ai

Bang Khae

Bang Khen

Lak Si

Bang Bon

Nongkham

Don Muang

Thung Kru

Chatuchak

Bangkapi


Bungkum

Kanna Yao

Dusit

Bang Na

Lat Phrao

Saphan Sung

Suan Luang

Chom ThongYannawa

Watthana

Bang Sue

Phasi Charoen

Huai Khwang

Ratburana

Bangphlat

Khlong ToeiSathon

Bangkok Noi


Phra Khanong

Thonburi

Din Dang

Pathumwan

Ratthewee

Bangkho Laem

Khlong San

Bangkok Yai

Bang Rak

Phra

Nakhorn

Pom Prap

Sattru Phai

Samphanthawong

5 0 5

Kilometers

2 0 2 4 Kilometers

Estimating spatialdisaggregation of urban

thermal stress

Thermal Stress (centigrade)

29.299 - 29.62229.622 - 29.94429.944 - 30.267

30.267 - 30.58930.589 - 30.91230.912 - 31.23431.234 - 31.55731.557 - 31.87931.879 - 32.20232.202 - 34.049

Minimum : 29.527Maximum : 34.049Mean : 30.267Std.Deviation : 0.645

(a.)

(b.)

(c.)

(Result)

※ All surface properties are unitless and normalize values (between 0 and 1)

A simple statistical hypothesized of

near-surface air temperature

The Spatial Patterns of Surface Morphological Variables and

Variation of Land Surface Temperature in the Summer

(4.) A GIS-Multivariate Analysis Approach to Delineate Thermal Climate Zones

Characterization of Bangkok

Calculating Fuzzy Membership of Each Urban and

Rural Landscape Class


* Thermal responsiveness is considered here as the summer diurnal range of the urban canopy layer (UCL) air temperature.

Bangkok area

consists of 7 different

categories of the

thermal climate zones

(TCZs) characterization

schemes

(a.)Nearest the final cluster center

(b.)Farness the final cluster center

The final cluster center

18

Combination of Multivariate Statistical Techniques with a Geostatistical

Approach such as Cluster Analysis (CA)

(5.) Distribution of Climate-based Urban and Rural Landform classes in the Bangkok

(i) Distribution of thermal climate zone (TCZ) classes (ii) Mean value of the surface morphological variables of TCZs

19


(a) Class 1 (b) Class 2

(d) Class 4(c) Class 3

(e) Class 5 (f) Class 6

(g) Class 7

Class 1—Extremely Low Density (ELD)

Class 2—Very Low Density (VLD)

Class 3—Low Density (LD)

Class 4—Medium Density (MD)

Class 5—High Density (HD)

Class 6—Very High Density (VHD)

Class 7—Extremely High Density (EHD)

Where:

Class 1 (n=3,794) Class 2 (n=1,305)

Class 3 (n=871) Class 4 (n=483)

Class 5 (n=91) Class 6 (n=63)

Class 7 (n=13)

Thermal Climate Zone (TCZ)

Bu

ild

ing C

ov

era

ge R

ati

o (

%)

Gre

en

Co

vera

ge R

ati

o (

%)

0

20

40

60

80

100

120

ELD VLD LD MD HD VHD EHD

0

20

40

60

80

100

120

Class 1 Class 2 Class 3 Class 4 Class 5 Class 6 Class 7

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0


Flo

or

Are

a R

ati

o (

un

itle

ss)

Urban Site Description The BMA’s TCZs* for each class Typical for nearest and farness the mean class centriod

of seven urban and rural classes Num. of Cases %

1. Extremely low density (ELD) Close to the edge of the city, this area is bordered

by farmland and has Chaophraya river and canal

running through it. Building type is a single dwelling

unit, cottage housing, or with one single-family

structure.

3,794 57.31

2. Very low density (VLD) Detached single family structures, horizontal

skyline of low-rise buildings (one- or two-story) and

well separated by open, paved spaces. Including

warehouses, wholesale, research and

development, and manufacturing uses.

1,305 19.71

3. Low density (LD) Two stories, Smaller detached homes. Buildings

separated by yards, and set along medium-width

streets. Small commercial structures, multi-story

mixed use and residential structures.

871 13.16

4. Medium density (MD) Low-rise apartment building or townhouses,

gardens, small trees (two- or three-story). Mixed

houses and small shop. Warehouse, light industrial

area or shopping mall with large paved or open

space.

483 7.30

5. High density (HD) Scattered tall towers, residential-closely spaced

less than four-story row and block buildings or

major facilities, town center, narrow street canyons,

e.g., old town centers, dense row, and

semidetached housing.

91 1.37

6. Very high density (VHD) High-rise apartment buildings (e.g., modern city

core, tall apartment, major institution),

Office/Midrise apartment building three-story large

or closely spaced, semidetached and row houses.

63 0.95

7. Extremely high density (EHD) Buildings are often large and dense, attached or

close-set , and homogeneous in character with

narrow streets. Heavy traffic flow.

13 0.20

(6.) A bridged definitions and values of geometric and surface cover properties for thermal climate zones (TCZs)

1A 2A 3A 4A

5A 6A 7A

(a) Nearest the mean class centroid for all seven classes

FAR=0. , BCR= . , GCR= .

(Mean class centroid)

FAR=0. , BCR= . , GCR= .

(Nearest the mean class centroid)

FAR=0. , BCR= . , GCR= .

FAR= .107, BCR=0.444, GCR=0.220

FAR= . , BCR= . , GCR=0.

FAR= .218, BCR=0.783, GCR=0.113

FAR=0. , BCR= . , GCR= .

FAR= .340, BCR=1.152, GCR=0.040

FAR= . , BCR= . , GCR= .

FAR= .603, BCR=1.623, GCR=0.012

FAR= . , BCR= . , GCR= .

FAR= .795, BCR=1.124, GCR=0.040

FAR= . , BCR= . , GCR= .

FAR=1.654, BCR=1.412, GCR=0.042

1B 2B 3B 4B

5B 6B 7B

FAR=0. , BCR= . , GCR= .

(Mean class centriod)

FAR=0.059, BCR=0.070, GCR=0.020

(Farness the class centroid)

FAR=0. , BCR= . , GCR= .

FAR= .066, BCR=0.341, GCR=0.332

FAR= . , BCR= . , GCR=0.

FAR= . , BCR= . , GCR= .

FAR=0. , BCR= . , GCR= .

FAR= .338, BCR=1.448, GCR=0.032

FAR= . , BCR= . , GCR= .

FAR= .653, BCR=2.214, GCR=0.008

FAR= . , BCR= . , GCR= .

FAR=1.174, BCR=1.565, GCR=0.018

FAR= . , BCR= . , GCR= .

FAR=2.266, BCR=1.683, GCR=0.016

(b) Farness the mean class centroid for all seven classes

20

(7.) Assessing the stability of local temperatures for different thermal climate

zones (TCZs) in the summer using surface temperatures

The land surface temperature (LST) has been shown to be highly

correlated with the near-surface air temperature [Srivanit M., et al,

2012;Weng Q. et al., 2009; Nichol J.E. et al., 2008].

a. Band1 (0.450-0.515 µm)

Pixel Res 30 m

Visible Blue

b. Band2 (0.525-0.605 µm)

Pixel Res 30 m

Visible Green

c. Band3 (0.603-0.690 µm)

Pixel Res 30 m

Visible Red

d. Band4 (0.750-0.900 µm)

Pixel Res 30 m

Near Infrared

e. Band5 (1.550-1.750 µm)

Pixel Res 30 m

Middle Infrared

f. Band6 (10.400-12.500 µm)

Pixel Res 120 m

Thermal Infrared

g. Band7 (2.080-2.350 µm)

Pixel Res 30 m

Middle Infrared

h. Example the digital

structure of Band 5

Digital Numbers & Gray color scale

Nu

mb

er o

f P

ixe

ls

0 255128

km

N

Derivation of LST from LANDSAT Imageries

minmin

minx

minx )()(

LQCALDNQCALQCAL

LLL

ma

ma

11

2

L

KIn

KTk

[Eqn.1]

[Eqn.2]

kT

1K2K1K2K

Where:

is the temperature in Kelvin (K)

is the prelaunch calibration of constant 1 in unit of W/(m2 sr·m) and

is the prelaunch calibration constant 2 in Kelvin. For LANDSAT TM,

is about 607.76 W/(m2 sr·m) and

is about 1260.56 W/(m2 sr·m)


21

22

(a.) (b.) (c.)

Mar5,1994 Feb18,2000 Apr25, 2009

(a.) (b.) (c.)

Mar5,1994 Feb18,2000 Apr25, 2009

1) Surface urban heat island (SUHI) changes in the city core of Bangkok

2) Changes on greenness

3) Surface temperature patterns related to urban landscape features

(7.) Assessing the impacts of urbanization on urban thermal environment of Bangkok (cont.)

Source: M.Srivanit and K. Hokao, August 2012

(8.) A simplified classification of distinct the thermal climate zones arranged in

approximate decreasing order of their ability to impact local climate

23


1

4

3

ø÷3242

ôó35

ø÷338

ø÷304

ø÷304

7

Nong Chok

Latkrabang

Minburi

Prawet

Bang Khun Thian

Khlong Sam Wa

Sai Mai

Bang Khae

Bang Khen

Lak Si

Bang Bon

Nongkham

Don Muang

Thung Kru

Chatuchak

Bangkapi


Bungkum

Kanna Yao

Dusit

Bang Na

Lat Phrao

Saphan Sung

Suan Luang

Chom Thong Yannawa

Watthana

Bang Sue

Phasi Charoen

Huai Khwang

Ratburana

Bangphlat

Khlong ToeiSathon

Bangkok Noi


Phra Khanong

Thonburi

Din Dang

Pathumwan

Ratthewee

Bangkho Laem

Khlong San

Bangkok Yai

Bang Rak

Phra

Nakhorn

Pom Prap

Sattru Phai

Samphanthawong

ClusterNumber of thermal climate zones

63

91

483

871

1,305

3,794

Area Sq.km. (percentage of study area)

948.50 (57.31%)

326.25 (19.71%)

217.75 (13.16%)

120.75 (7.30%)

22.75 (1.37%)

15.75 (0.95%)


Classifying thermal climate zone using K-means cluster analysis

2000 0 2000 4000 Meters

Dusit

Watthana

Huai Khwang

Bangphlat

Khlong ToeiSathon

Phayathai

Thonburi

Din Dang

Pathumwan

Ratthewee

Khlong San

Bangkok Yai

Bang Rak

Phra Nakhorn

Pom Prap Sattru Phai

Samphanthawong

3

5 0 5 10 Kilometers

1

2

3

4

5

6

7 3.25 (0.20%)13

Extremely Low Density (ELD)

Very Low Density (VLD)

Low Density (LD)

Medium Density (MD)

High Density (HD)

Very High Density (VHD)

Extremely High Density (EHD)

Thermal Climate Zones

34.0

36.0

38.0

40.0

42.0

44.0

46.0


Thermal Climate Zone (TCZ)

Lan

d S

urf

ace

Tem

per

ature

(C

elsi

us)

(b) The stability of surface temperature for different thermal

climate zones in the summer of Bangkok (a) An urban thermal environmental map (UTEMap)

The result found that the urban-rural temperature difference, or urban heat island

intensity (UHII), can often exceed ~ 4.23 ºC in the summer.

Table : Correlation coefficients (the Spearman’s rho) between the variation of land surface temperature

and urban morphology descriptors of thermal climate zones.

Surface Morphology Feature Thermal Climate Zones (TCZs) Urban

Level ELD VLD LD MD HD VHD EHD

1.Building coverage ratio (BCR) .608** .532** .484** .455** .871** .470** .346 .885**

2.Floor area ratio (FAR) .606** .424** .187** .106** .307** .176 .313 .876**

3.Green coverage ratio (GCR) -.134** -.306** -.225** -.207** -.278** -.369** -.468 -.577**

Note: Significance level at **p < 0.01, *p < 0.05

(9.) Major Factors Responsible for Thermal Climate Zone (TCZ)’s

Temperature Stability

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The similarity in the highest LST variations (with a mean LST of ~41.72 ºC) of High

Density (HD) areas can be explained relating to a high proportion of built-up surface

covers and a lowest amount of green space.

While the lowest LST variations were observed for low density residential,

agricultural and natural cultivation zones (with a mean LST of ~37.49 ºC).

10.) CONCLUSIONS

The Bangkok area consists of 7 different categories of

the thermal climate zones (TCZs) characterization

schemes, each distinguished by its surface configuration

and composition properties that have a roughly similar

propensity (homogeneous) to modify the local climate.

The local thermal stability is significantly different among

the TCZ types. The large thermal variations caused by

the intra-urban morphological heterogeneity are

consistent with the findings in other areas. It is possible

to attain a low regional thermal variation by planning

different TCZs in a reasonable configuration.

International Conference on Southeast Asian Weather and Climate 2013 “ASEAN Adapting to Climate Change” 25

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11.) Conceptual Framework of Integrated the Multi-scale Urban Climatic Assessment

[Source: Author]

A City-wide

In

BetweenUrban Rural

Regional Metadata-sets

Geographical database

Remote sensing

Official surveys

Local Authority Information

Meteorological stations

Building typologies and

configurations

An Urban Thermal

Environment Map (UTEMap)

for Spatial Planning

Spatial-temporal dynamics in

response to urbanization

Urban thermal remote sensing

& vegetation distribution

Quantify the surface properties

of the thermal source area

Mapping on GIS and analysis

using methods including SPSS

Local/Micro Climatic Data

Climate observational

Micro-climate numerical

modeling assessment

Measuring the Local Climatic

Character of Their Sites

Quantify Benefit of Local

Climate Improvement

Optimum Greening Design

And Management Method

Development of greening

modifications

Greening benefits derived

from solving problematic

Etc.

Guidelines for Using Climate

Zones Classification

Updating Site Designations

Develop A Climate-based Classification System

Select the thermal climate zones (TCZs)

Multi-scale Climatic Information

Planning and Management

Settlement Climatic

Information Decision Making

Guidelines for Local

Environment Improvement

Settlement/City-wide Level

Climatic Mapping

Planning with Local Climate in

Different Climatic Zones

More Objective Guiding the

Spatial Planning Decision

Process

“METUTOPIA”

MESOSCALE LOCAL/MICROSCALE

“METUTOPIA” is a meteorogically optimized urban planning and design

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Integrated suite of tools for multi-scalar assessment should have levels of observation in

urban climate studies and parameters of pleasant outdoor environment analysis

Levels of Observation Parameters of Analysis

Building

(Individual building, Parcel)

Building Groups

(Block, or Thermal Climate Zone-TCZ,

Neighborhood, District)

A City Settlement

(Climate-based Landforms

Classification System)

Building placement

Outdoor landscaping (open

spaces and greening)

Materials and surfaces

Street dimensions & orientation

Shadow areas

Location

Materials

Type of building

Design (e.g. shape, orientation, etc.)

Occupant behavior

Zoning

Overall extent, shape and pattern

Guidelines on (densities; heights;

land uses; and green-spaces)

Green infrastructure planning

Transport policy

Objective

Building Form

Design

Outdoor Comfort and Health

(The Optimum Planning and

Design System)

A Climate-based Urban Development Pattern Approach (CUDPA) [Source: Author]

Thanks you for your attention.


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