landscape architecture group, wageningen university€¦ · dipl. ing. wiebke klemm landscape...

DIpl. Ing. Wiebke Klemm

Landscape Architecture Group, Wageningen University

Impact of urban green on thermal comfort

on warm summer days in Utrecht,

The Netherlands

Dipl.Ing Wiebke Klemm

Wageningen University, Landscape Architecture Group

Dipl.Ing Wiebke Klemm1, Dr. ir. Bert Heusinkveld2, Dr. Dipl.Ing Sanda Lenzholzer3, Dr. ir. Bert van Hove3

1-3 Wageningen University, Landscape Architecture Group, 2 Wageningen University, Meteorology and Air Quality Group

4 Wageningen University, Meteorology and Air Quality Group/ Earth System Science Group

CCRR – CLIMATE CHANGE AND REGIONAL RESPONSE DRESDEN 2013



Parks are ‘cool-spots’ in the city - thermal comfortable spaces

for inhabitants on warm summer days

... especially against the background of climate change and urban heat

island effects.



For landscape architect especially the spatial aspects of parks, which

cause those comfortable microclimates, are interesting.

Knowing those spatial aspects (and their physical and psychological

impact), landscape architects, are able to design thermal comfortable

urban green spaces.

Towards design guidelines for urban green...



Research questions

1. What are the magnitudes of the cooling effects of various parks in a

city on warm summer days (Ta > 20°C)? Which spatial aspects of

parks influence the cooling aspect?

2. What are inhabitant’s spatial preferences and usage of parks on warm

summer days (Ta > 20°C)?



Research methods I

Micrometeorological measurements,

(6 days, in July and August 2012, Tair average 24.5 °C)

Cargo-bicycles, equipped with sensors for

- air temperature,

- humidity,

- wind and

- radiation sensors.

Calculating

Mean radiant temperature (Tmrt)

Case Utrecht, The Netherlands – Urban green/ bicycle routes for measurements



Air temperature in various parks in Utrecht July 24th, 2012 (12:00-17:00 UTC)

Air temperature in (°C)

Wind from SE



Air temperature in 7 parks in Utrecht July 24th, 2012 (00:00-20:00 UTC)

12

14

16

18

20

22

24

26

28

30

32

0:0

0

2:0

0

4:0

0

6:0

0

8:0

0

10

:00

12

:00

14

:00

16

:00

18

:00

20

:00

Air

te

mp

era

ture

(°

C)

Wilhelminapark Beatrixpark Park Transwijk Park Oog in Al

Marjellapark Gagel Park Giftpark Square city centre



Temperature/ wind speed for 7 parks in Utrecht, 13:33-14:59 UTC, July 24th 2012

0

1

2

3

4

5

6

0

10

20

30

40

50

60

70

Win

d s

peed

(m

s-1

)

Tem

pera

ture

(°

C)

Ta Tmrt Wind speed



Research methods II

Interviews with pedestrians

(181 in total, on 15 days from July to September

in 2011 and 2012)

1. Could you indicate how comfortable you would feel on a hot summer day

in one of the following urban spaces?

2. Where do you go to on a hot summer day within a time frame of: <2

hours, half a day, one day, one weekend?

3. Which specific places within the city you find most comfortable in terms

of temperature on hot summer days?

Example of a ‘ mental map’ of favourite urban spaces on warm summer days

Case Utrecht, The Netherlands – Location of interviews (n=181)



Who were the respondents (n=181) ?

Sex

m w

Age

<20 20-30 30-40 40-50

50-60 >60 geen

Private outdoor space

nee balkon/terras tuin no response



1. Could you indicate how comfortable you would feel on a hot summer day in one of the

following urban spaces?

,0

10,0

20,0

30,0

40,0

50,0

60,0

Water

beach lake swimming pool canal

,0

10,0

20,0

30,0

40,0

50,0

60,0

Stone

parking lot shopping street

square outdoor cafe

0

10

20

30

40

50

60

Greenery

forest rural area park garden



0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

<2uur 4uur 8uur 16uur

Outside city

City

Neighb

Street

Garden

Inside

2. Where do you go to on a hot summer day within a time frame of: <2 hours, half a day, one

day, one weekend?



3. Which specific places within the city do you find the most comfortable in terms of

temperature on hot summer days?

0

10

20

30

40

50

60

City centre

Park

Water



Thank you for your attention.

Contact information:

Dipl.Ing. Wiebke Klemm

Email: [email protected]

Adres: Droevendaalsesteeg 3, 6708 PB Wageningen, The Netherlands

landscape architecture group, wageningen university€¦ · dipl. ing. wiebke klemm landscape...

Documents