By 2O4_Group 5:

1.Barry Lee Wenhao2.Shaun Lee Tz Wei3.Delvin Chua Ming Rui4.Cleve Lim Rui Han5.Woo Zhiying

Human ThermometerBased on the aspect of ‘feel’, we visited the 7

locations, estimated the temperature of the places, and ranked them.(Hottest->1 ; Coolest-> 7)

Sites Ranking

A (Top floor of Multistorey Carpark) 4

B (Garden outside printing centre) 6

C (The Globe at the Clock Tower 7

D (Terraces) 2

E (Field) 3

F (Running Track) 1

G (Fountain area outside General Office)

5

Initial Reasoning- Site A•Although the carpark had concrete floor and was open air, it did not feel as if the hottest place amongst the 7 listed places.

•We attributed this to: -Higher Altitude of the top floor of the carpark, thus resulting in a lower temp. -Presence of thick cloud cover when we visited the location.

Initial Reasoning- Site B•Although the Garden is open air, however, it felt like one of the coolest places, second to The Globe.

•We attributed this to: -Grass and various kinds of vegetation -A few trees (~40m) provide shade from direct sunlight

Initial Reasoning- Site C•The Globe was definitely the coolest place.

•We attributed this to: -The Globe is the only one of the 7 locations indoors -Sheltered from high insolation -Faces direction of wind -Marble Flooring is a good conductor of heat and thus feels ‘cool’ to the touch

Initial Reasoning- Site D•The Terraces was ranked the second, after the Running Track in terms of temperature.

•We attributed this to: -The exposed surface area is larger due to the shape of the terraces. -Moreover, the terraces around made up of concrete which radiates more heat than a non-concrete surface. -Trees a the top of the terraces make minimal impact towards the temp.

Initial Reasoning- Site E•The Field is open air and has no obstructions nearby. However, it was not the hottest

•We attributed this to: -The large area of grass which radiates a lot less heat as compared to the concrete ground of the terraces and the vulcanized rubber flooring of the track.

Initial Reasoning- Site F•Using the sense of touch, we ranked Site F the hottest.

•We attributed this to: -Dark-coloured track exposed to direct sunlight. Thus, more of the heat directed at it is absorbed. -Vulcanized Rubber is a poor conductor of heat.

Initial Reasoning- Site G•We felt that the temperature of Site G was a moderation between the highest and lowest, thus explaining its rank, 5.

•We attributed this to: -Although water feature increases humidity, we believe it cools down the surroundings. -Shaded by various blocks.

Hypothesis1) Shady areas are generally cooler

than places without shade

2) Areas with concrete surfaces are generally hotter than places without concrete surfaces

Actual Exercise

Sites Temperature 15cm above ground (°C)

Temperature 1.5m above ground (°C)

Relative Humidity (%)

Wind Speed (m/s)

Description of surroundings

A 31.3 31.4 56.1 0 Concrete ground, cars, buildings

B 31 31.3 55.3 0.8 Vegetation, building structures, grass

C 30.7 30.8 54.3 1.5 Indoors, marble flooring,

D 32 31.8 53.3 2.6 Concrete ground, some shade from trees

E 34.8 33 51 2.2 No shade, Grass

F 33.7 31.8 50.9 1.4 No shade, ground made of vulcanized rubber

G 32 31.7 56 1.3 Concrete ground, buildings.

Time conducted: 12.45pm

Site A- Top Storey of Carpark

Reasons for 3rd lowest temperature, highest humidity and lowest wind speed:

-Although the area has concrete ground, but it is shaded by the Staffroom Block (building obstructions caused the lowest wind speed)

-Thick Cloud Cover at the time of recording resulted in the highest humidity

Site B- GardenReasons for 2nd lowest temperature, high humidity and 2nd lowest wind speed:

-In addition to being shaded by building structure (Blk B), the area is shaded by tall trees (~40m) and has non-concrete ground. This explains its relatively low temp.

-The relatively high humidity can be attributed to the vegetation in the area which transpire and release excess water vapour via the stomata of leaves.

Site C- The GlobeReasons for lowest temperature, relatively high humidity and average wind speed:

-Indoors, sheltered by Clock Tower

-Although indoors, it faces the direction of the wind, thus it has average wind speed.

-Marble Flooring is a good conductor of heat.

Site D- TerracesReasons for 3rd highest temperature, relatively high humidity and highest wind speed:

-Concrete Flooring radiates much heat

-Little Shade (there are some trees, but they have minimal impact on both wind speed and temperature)

-No Obstructions from buildings

Site E- FieldReasons for highest temperature, low humidity and relatively high wind speed:

-Discrepancy: Based on initial recording, we believed this was not the hottest location due to the non-concrete ground.

-On the other hand, the field could be the hottest because it was DIRECTLY under the NOON sun. Moreover, its relatively large dimensions mean that it is not blocked by any structure at all. Thus resulting in it having the highest temperature.

Site F- Running TrackReasons for 2nd highest temperature, lowest relative humidity and average wind speed:

-Vulcanized Rubber Track is a poor conductor of heat.

-Dark-colored track absorbs heat.

Site G- Fountain AreaReasons for average temperature, highest relative humidity and relatively low wind speed:

-Obstruction by building structures(Staffroom Block and Blk B)

-Water Feature cools down the temp, but also causes more moisture content in the air, thus explaining the highest relative humidity.

ConclusionRecap:

Hypothesis 1) Shady areas are generally cooler than places without shade.

Non-Shaded Areas

Site A (31.4°C)

Site D (31.8°C)

Site E (33°C)

Site F (31.8°C)

Site G (31.7°C)

Average Temp: 31.94°C

Shaded Areas

Site B (31.3°C)

Site C (30.8°C)

Average Temp:31.05°C

From these results, we can see that the average temperature for shaded regions are lower, as compared to the non-shaded regions, thus proving our hypothesis correct.

ConclusionRecap:

Hypothesis 2) Areas with concrete surfaces are generally hotter than places without concrete surfaces.

Non-concrete Areas

Site B (31.3°C)

Site C (30.8°C)

Site E (33°C)

Site F (31.8°C)

Average Temp: 31.725°C

Concrete Areas

Site A (31.4°C)

Site D (31.8°C)

Site G (31.7°C)

Average Temp:31.63°C

From these results, we can see that the average temperature for concrete regions is slightly lower, as compared to the non-concrete regions, thus proving our hypothesis wrong.

Clarification 1. It is a known theory that concrete

surfaces are hotter than non-concrete surfaces. However, we realized that in real-life situations, this is not the case due to varying factors:

-Dimensions of the location (eg. The field is relatively large, as such it is not obstructed by any building structure) -Surrounding Buildings (Shade) -Water Feature (Cools down the surrounding air)

Clarification cont. •Therefore, such factors will affect the outcome, even if the area is made up of concrete ground or not.

2. Varying floor materials conduct heat differently, and this is not dependent on whether the floor is concrete or not. Eg. Vulcanized Rubber Track. The material is a poor conductor of heat, thus it radiated as much heat as a concrete surface.

Clarification cont. 3. Our group believes that the wind speed we have measured for the varying locations are inaccurate. This is because during our short ‘fieldtrip’, there were sudden gusts of wind, which affected the results for certain locations.

Improvement1. To ensure the results are more accurate,

record the weather conditions at the area at exactly the same time (there may be sudden gust of wind, thus to ensure accuracy, there must be no time interval)

2. Since we have not been convinced that concreted areas are hotter, we hope to be able to conduct repeated experiments at different times of the day, after which taking the average and re-comparing the results.

THANK YOU!