Tropical Design- Climate1 (1)

8/13/2019 Tropical Design- Climate1 (1)

http://slidepdf.com/reader/full/tropical-design-climate1-1 1/15



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climate• The air close to the surface is heated

and rises, creating low pressure.

• As the earth is not heated evenly,

pockets of relatively high and low

pressures are formed over its surface

and wind is a direct consequence of

this pressure differential, as air is

moved from areas of high pressure to

areas of low pressure.

Weather and

climatic forces

are products of

solar radiation.

The atmosphere

of the earth

absorbs solar

energy which in

turn warms the

planet’s surface.



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Climatic Factors

1. Solar Radiation

a. UV Radiation

b. Visible Light

c. Short Infra-RedRadiation (RadiantHeat)

2. Tilt of the Earth’s Axis

3. Thermal Balance

4. Winds

5. Topography



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Climatic Elements

1. SOLAR RADIATION – absorbs direct scatteredsource of almost all earth’s energy occurs inshort wavelengths.

Radiant Heat Affects the Structures

a. Direct Short Wave Radiation

b. Diffused Short Wave Radiation

c. Reflected Short Wave Radiation

d. Long Wave Radiation (From heatedground and surrounding structures)



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Climatic Elements

2. AIR TEMPERATURE – annual, monthly and

diurnal maximum and minimum temperature.

Dry Bulb Temperature (DBT) – This is the

measurement of the temperature of the air

and as far using a thermometer and can eitherbe in units of Fahrenheit or Celsius.



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Climatic Elements

3. ATMOSPHERIC HUMIDITYa. Absolute Humidity – amount of moisturepresent in the air (g/m3)

b. Specific Humidity – weight of unit vapor perunit weight of air (g/kg)

c. Vapor Pressure – partial pressure of water vapor presentin the air

d. Relative Humidity (RH) – refers to the amountof water in the air. RH is measured usinghygrometer and can be in the form of Wet Bulb

Temperature (WBT) in Fahrenheit or Celsius or inRelative Humidity (RH) in percent (%).

RH = abs. hum. X 100

saturation point

RH = Act. Amt of moisture present

Amt. of moisture the air could hold

Climatic Elements

4. PRECIPITATION – data in the form of total

monthly rainfall of maximum rainfall

during the 24 hr. period. This is mainly

rainfall but can also be in the form of dew.

Precipitation is measured using rain gauge in

units of inches or centimeters.



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Climatic Elements

5. WIND – The direction, frequency and force of

the wind throughout the year.



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MICROCLIMATIC CONDITIONS

1. Time of Day

2. Topography

3. Water

4. Ground Surfaces

5. Vegetation

World climates



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General Types of Climate

1. Hot Humid (Tropical)

2. Hot Arid

3. Temperate

4. Cold



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Thermal Comfort

• Human comfort as determined by the ability

of the body to dissipate the heat and moisture

it produces by metabolic action.

• Thermal Comfort is a condition of both

physical and mental well-being, and designers

are responsible for providing an internal

climatic environment that can produce it.



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• The ventilation of a building is directly related

to thermal comfort. By increasing the air

velocity, the comfort zone shifts to a higher

temperature.

• This means that occupants of the building will

feel more comfortable, even though the

building is not actual being cooled.



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Microclimate

• If a building is to relate to and gain from its

environment, it is important to understand

regional weather patterns, but the

microclimate of the area must also be

carefully examined.

The following factors can alter the

macroclimate to produce a quite different

microclimate:• TIME OF DAY

– Day and night will produce two quite different

conditions sometimes reversing the direction of

the prevailing wind. This is particularly the case in

mountainous regions, where air will rise up a

mountain during the day and fall during the night.

– Large bodies of water can also have the effect of

reversing the wind flow as day turns to night.



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microclimate:• VEGETATION AND SOIL TYPE

– Vegetation can produce enclosed conditions,either altering or reducing the wind speed ordirection. The heat capacity, color and watercontent soil will affect the amount of heatabsorption and therefore the groundtemperature.

– This can have a significant effect on the

microclimate because the ground temperatureinfluences pressure systems.



microclimate:• MAN-MADE STRUCTURES

– The built environment can significantly alter a

microclimate. Overall, wind speed will be 25%

lower in built-up areas, though very high local

wind speeds can occur due to urban canyons

(buildings and streets that channel wind flow).



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microclimate:• TOPOGRAPHY

– Generally, wind speeds will increase with altitude.The steeper the slope of land, the faster thetemperature will drop at night, and this will alterthe wind direction.

– The topography of the earth’s surface has a majoreffect on microclimate, diverting or blockingwinds, are therefore more desirable than north-facing slopes.



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microclimate:• PROXIMITY TO BODIES OF WATER

– The proximity of land to a water mass will create air

currents. Water has a high heat capacity and therefore

large water mass will not absorb heat as quickly, but

will retain it longer than a similar area of land mass.

– Temperature changes over water therefore tend to be

more moderate and produce a different pressure

system from that over land. This pressure difference

can generate daily alternating land and sea breezes.

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Tropical Design- Climate1 (1)