HT MOD I PPT..pptx

Syllabus
 Climatology:- Definition – Climate and Weather – Solar Radiation – Quantity
and Quality – Earth's Thermal balance – Winds – Types of Wind – Characteristics
of Wind force and speed.
 Site Climate/Micro Climate:– Local factors, temperature and humidity – Air
movement - Vegetation – Urban Climate – Site Climate Data – Macro Climate.
 Sustainable Development:– Definition – Sustainable materials and
technologies, Global efforts for Sustainable Development – Protection of
Atmosphere, Air, Water and Earth, Environmental Management.

HABITAT ENGINEERING
Habitat : The normal locality inhabited by a plant or animal particularly in
relation to the effect of its environmental factors is known as habitat.
Habitat Engineering : The engineering related to the development of
residential areas which satisfy all the basic needs of the human beings
without damaging the environment factors is known as habitat engineering.
Basic needs of human – fresh air, pure water, moderate climate, food, social
life, etc.,
Environmental factors – air, water, climate, solar radiation, soil etc.,

CLIMATOLOGY
Climatology :
 The branch of atmospheric science concerned with both the description
of climate and the analysis of the causes of climatic changes and their
practical consequences.
 Scientifically defined as weather conditions averaged over a period of
time.
 Climatologists study both the nature of climates (local, regional or
global) and the natural or human-induced factors that cause climate to
change.
 Climatology considers the past and help to predict future climate

CLIMATE & WEATHER
Weather
 Weather describes whatever is happening outdoors in a given place at a
given time
 It can change a lot within a very short time. For example, it may rain for
an hour and then become sunny and clear.
 It includes daily changes in precipitation, pressure, temperature, wind
etc., in a given location
 More specifically, weather is the mix of events that happen each day in
our atmosphere.
 The weather isn’t the same all around the world. Weather is different in

CLIMATE & WEATHER
Climate
 Whereas weather refers to short-term changes in the atmosphere, climate
describes what the weather is like over a long period of time in a specific
area.
 It is the average weather pattern in a place over a long period of time
(many years)
 This includes average weather conditions, regular weather sequences
(like Summer, Winter, Rainy) and special weather events (like cyclones
and floods).
 Different regions can have different climates.

FACTORS SHAPING CLIMATE
Solar Radiation (Quality & Quantity)
Earth’s Thermal Balance
Insolation
Temperature
Humidity & Precipitation
Wind

Solar Radiation – Quality
 Radiation means to send out rays
 Solar radiation is radiant energy emitted by the sun from a nuclear fusion
reaction that creates electromagnetic energy.
 It provides light and heat for the Earth and energy for photosynthesis.
 This radiant energy is necessary for the metabolism of the environment
and its inhabitants
 Solar radiation spectrum extends from 290nm to 2300nm.
 The three relevant bands along the solar radiation spectrum are
ultraviolet rays, visible light and infrared rays.

Solar Radiation – Quality
 The three relevant bands along the solar radiation spectrum are
ultraviolet rays, visible light and infrared rays.
 Ultraviolet radiation : 290nm to 380nm
 Visible light : 380nm to 700nm
 Infrared radiation : 700nm to 2300nm
 Most of the solar radiation that reaches Earth is made up of visible and
infrared light. Only a small amount of ultraviolet radiation reaches the
surface.
 Not all radiation emitted from the sun reaches Earth’s surface. Much of it

Solar Radiation – Quantity
 Solar radiation is measured in wavelengths or frequency.
 As light travels in a wave, a wavelength is defined as the distance from
peak to peak and is measured in nanometers (nm).
 Frequency is defined as wavelength cycles per second and is expressed
in hertz (Hz). Bands with shorter wavelengths produce higher
frequencies.
 The energy of the wavelength increases with the frequency and decreases
with the size of the wavelength. In other words, shorter wavelengths are
more energetic than longer ones.

Solar Radiation – Quantity
 The quantity of solar heat transmitted in one minute to one square cm of
earth surface normal to the sun rays beyond the earth atmosphere is
defined as solar constant which is approximately 2 cal per sq cm per
minute.
 Most of this radiation is perceived as heat and only a small part as visible
light.

Earth’s Thermal Balance
 The total amount of heat absorbed by the earth each year is balanced by a
corresponding heat loss. This is known as earth’s thermal balance.
 Without this balance the temperature of the earth would increase
tremendously and the earth may become unfavourable to most forms of
life.
 (Refer text also)

Insolation
 The amount of solar radiation which reaches a particular area is known
as insolation.
 It depends on solar altitude during the day, the incident angle of the sun
rays, latitude, duration of radiation received, elevation above sea level
and atmospheric conditions.

Temperature
 The atmosphere is heated in two ways; by direct absorption of solar
radiation and by the absorption of heat from the earth surface.
 When the lower layers of the air are heated its density decreases and this
layer of the air rises up.
 The resulting vertical convection current carry heat to the upper layers of
the atmosphere.
 The ocean currents and the direction of prevailing winds in an area is an
important factor in air temperature variation.

Humidity & Precipitation
 Atmospheric humidity is the amount of water vapour or moisture in the
air.
 Abosolute humidity is defined as the amount of water vapour to be found
in air for any given time and is expressed in g/m3 of air.
 A major factor influencing abosolute humidity is temperature.
 Precipitation occurs due to the condensation of the water vapour in the
atmosphere and it includes rainfall, snowfall, drizzle etc.,

Wind
 Wind is the movement of air masses in horizontal direction
 The wind speed is expressed in m/sec
 A difference in temperature causes a difference in pressure.
 Equillibrium of pressure is the basic principle of wind movement. Air
moves from high pressure areas to low pressure areas inorder to establish
a state of relative equillibrium which resuls in wind.

Types of wind
Local wind
 They are caused by local changes in temperature
 The sun heats land and water differently
 Over the water bodies most of the heat energy is used in evaporation
or is absorbed by the water. Hence air is not heated very much.
 But in case of land surface, the amount of heat absorbed is very less
and also there is no evaporation. Hence the air over the land gets
heated more than that of air over the water bodies.

Types of wind
Local wind
 Local winds are the ordinary winds.
 They are influenced by various landforms such as vegetation, hill,
plains, water bodies, mountains and so on.
 The changes are because of different temperatures and pressure
regions during the night and day.
 The speeds of local winds range from mild to strong but just for a
few hours, and they only blow over short distances.
 Common examples of local winds are the land and sea breezes, and
valley and mountain breezes

Types of wind
Local wind
 Soon after sunrise, the heated air over the land becomes lighter
whereas the air above the sea remains denser. Due to this the denser
air over the sea starts moving towards the land where it pushes the
lighter air over the land up out of its way. This movement is called
sea breeze.
 During night the land cools more quickly than sea. Thus the air
above land will be denser and air above sea will be lighter. Due to
this the dense air over the land starts moving towards the sea and
this movement is known as land breeze.

Types of wind
Planetary wind
 The winds blowing throughout the year from one latitude to another
in response to latitudinal differences in air pressure are called
“planetary or prevailing winds”. They involve large areas of the
globe.

Types of wind
Trade wind
 These are extremely steady winds blowing from sub-tropical high
pressure areas (30°N and S) towards the equatorial low pressure
belt.
 These winds should have blown from the north to south in Northern
Hemisphere and south to north in Southern Hemisphere, but, they
get deflected to the right in Northern Hemisphere and to the left in
Southern Hemisphere due to Coriolis effect and Ferrel’s law.
 Thus, they blow as north eastern trades in Northern Hemisphere and
south eastern trades in Southern Hemisphere.

Types of wind
Westerlies
 These winds blow from sub tropical high pressure belts towards
sub-polar low pressure belts.
 The westerlies of Southern Hemisphere are more stronger and
constant in direction than Northern Hemisphere.
 These winds develop between 40° and 65°S latitudes and these
latitudes are known as Roaring Forties, Furious Fifties and Shriek-
ing Sixties.

Types of wind
Polar Easterlies
 The polar easterlies are also referred to as polar Hadley cells.
 They are the prevailing cold and dry winds that propel from the
high-temprature regions of the polar heights at the south and north
poles moving towards the low-pressure regions within the
westerlies at high latitudes.
 Polar easterlies blow from the east to the west and are generally
irregular and weak.
 Due to the low sun angle, there is a buildup of cold air and it
subsides at the poles creating surface high-pressure areas.

Types of wind
Monsoon winds
 Monsoons are seasonal wind in southern Asia blowing from the
southwest (bringing rain) in summer and from the northeast in
winter.
 These winds last for many months within the tropical regions.
 The term was coined to mean large seasonal winds moving from the
Arabian Sea and Indian Ocean in the southwest bringing heavy
downpours in the regions.
 Its directional movement towards the poles is speeded up by the
development of low heat areas over Australia in December and over

MICRO & MACRO CLIMATE
The climate of the earth consists of a series of interlinked physical systems
powered by the sun.
 Macro-climate - the climate of a larger area such as a region or a country
 Micro-climate - the variations in localised climate around a building
 The macro and micro climate has a very important effect on both the
energy performance and environmental performance of buildings, both in
the heating season and in summer.
 The site and design of a building can have a profound effect upon the
interaction between a building and its environment.

Factors affecting site climate/micro climate
Air Temperature
Humidity
Precipitation
Vegetation
Urban climate
Site climate data
Air movement

Air Temperature:
 The air temperature near the ground is dependent on heat gained/lost
by the earth surface.
 Heat exchange varies with day/night, season, time of the year,
latitude and cloud cover.
 During the day, with the heating of the earth surface, the air nearest
to the ground (within 2 metres) gains most temperature. At night, the
direction of heat flow is reversed.

Humidity:
 Relative humidity is inversely proportional to temperature.
 During the day, when the lowest layer of air is heated by the ground
surface, relative humidity decreases rapidly.
 This leads to higher rate of evaporation (If there is water body,
vegetation, etc.) leading to increase in absolute humidity.
 At night, when dew point temperature is reached, fog formation takes
place and if there is no further rapid cooling or air movement, a deep
layer of fog develops.

Precipitation:
 When ground level changes by more than 300m, the windward side
receives more rainfall than the regional average.
 In an extreme case, on a large site located on the top of a hill and
extending down to both the slopes, the leeward side receives only
25% of the rain received by the windward side.
 REASON: hill forces the air mass to rise which cools it down and it
is no longer able to support the moisture carried. The opposite is also
true. SKY CONDITIONS • Abrupt change in topography may cause
a permanent cloud cover like in the rock of Gibraltar.

Vegetation
 Vegetation is usually regarded as a function of climate but it itself
can influence the local or site climate.
 Forming an intermediate layer between the earth surface and the
atmosphere, they have a moderating effect on air temperature,
humidity, radiation and air movement.
 They increase the surface of contact to a higher layer by a factor of 4
to 12 times.
 Trees provide shade and affect the micro climate of the place.
 Trees and shrubs give off moisture (evapotranspiration) that

Urban Climate
 Man made environments create micro climate of their own deviating
from the regional climate.
 The factors causing deviation are changed surface qualities
(pavements and buildings), increased absorbance of solar radiation,
reduced evaporation.
 Buildings: Casting a shadow, acting as barriers to winds,
channelizing winds, storing heat in their mass and releasing it at
night.
 Energy seepage: through walls and ventilation of heated buildings

Site Climate Data
 Data relating to the regional macro climate is available almost
everyehere.
 As the climatic parameters for a site are same as for a region, it is
best to start with the summary of regional data and examine which of
the parameters will be affected by local specific factors and what
extend of such deviations is likely to be.
 The climate graph and the values included in the tables can be
changed accordingly.

Air Movement
 Air flowing across any surface is subjected to frictional forces. Wind
speed near the ground is less than the speed higher up and their
difference depends on the smoothness of the surface.
 On hilly sites, the greatest speeds are experienced at the crest of the
hills. The valleys may experience wind speed if their direction
coincides wit the direction of the wind flow.
 Large stretches of water can give rise to local coastal breezes.
Breezes from water to land during the day may lower the maximum
temperature by 10 degree Celsius but are likely to increase humidity.

SUSTAINABLE DEVELOPMENT
The idea of ‘sustainable development’ became widespread with the 1987
publication of ‘Our Common Future’, a report from the World Commission
on Environment and Development (the Brundtland Commission).
"Sustainable development is defined as the development that meets the needs
of the present, without compromising the ability of future generations to
meet their own needs."
Sustainable development is a way for people to use resources without the
resources running out. It means doing development without damaging or
effecting environment.

Concepts of sustainable development
The earth has limited supply of resources
Recycling and the use of renewable resources will prevent depletion
Lifes value does not depend on our material wealth
The cost of a project must include external cost such as damage to health and
environment along with the costs of energy, labour and material.
We must understand nature and develop a symbolic relationship
We are part of nature and should abide by its rules
We should minimise the wastes by recycling as far as possible

Sustainable materials
A sustainable material is any material that can be put to effective use in the
present without compromising its availability for use by future generations.
These are mainly renewable materials or the materials which can be recycled
and reused.
Two main sources of sustainable materials – Renewable materials and
Materials reused from wastes
MATERIALS FROM RENEWABLE SOURCES: Materials significantly of
plant origin. Can be obtained from renewable sources like solar energy, wind
energy, bio-gas etc. E.g. wood, natural fibers, etc.
REUSE FROM WASTE PRODUCTS AS RAW MATERIALS: They are

Sustainable materials
WOOL BRICKS: Obtained by adding wool and natural polymer found in
seaweed, to the clay of the brick. 37 % more strength than the burnt bricks.
Resistant of cold and wet climate. They don’t need to be fired like other
bricks.
SUSTAINABLE CONCRETE: Crushed glass, wooden chips or slag can be
added to make it sustainable concrete. Reduces CO2 emission of the
building.
SOLAR TILES: They spend a large portion of the day absorbing energy
from the sun. Not fixed on the top of the existing roofing like other solar
units. Instead they are fully integrated into the building. Protects from
weather as well as generates energy for the inhabitants.

Sustainable Technologies
Sustainable technologies have come a long way in the past few decades,
driven by environmental awareness and the rising costs of fossil fuels.
Nanotechnology
 This tiny technology has applications in clean energy, greenhouse gas
management, green manufacturing and sustainable living. In India,
for example, researchers are using composite nanoparticles to destroy
contaminants such as bacteria and microbes in drinking water.
Next-Generation Nuclear Power
 Next-generation nuclear power encompasses low-carbon ideas such
as advanced fission reactors, fusion-fission hybrids and pure

Biofuels
 Biofuels include ethanol and biodiesels produced from oils and fats,
as well as solid fuels made from non-food feedstocks, manure, waste
materials and algae.
Bioplastics
 Current forms of bioplastics include starch-based PLA and PHA
plastics. As oil supplies dwindle, many industries, such as the
automobile and electronics industries, may look to ecoplastics as
low-carbon alternatives. According to Helmut Kaiser Consultancy,
over 5,000 bioplastics processing companies are expected to be in
operation by 2020.

Smart Monitoring and Predictive Analytics
 Monitoring and analytics can help increase efficiency in energy
consumption, water use and green manufacturing. Companies can
use sensors to detect faults (such as leaks in water supply networks)
and predictive modeling to maximize resources (such as precision
irrigation systems).
Tidal Energy
 Tidal energy may have a strong future if investors are interested.
Unlike wind or sunshine, tides are fabulously predictable. The city of
Swansea in the United Kingdom is planning a 240-megawatt tidal
power plant that would generate over 400 gigawatt hours of

Agencies that provide assistance for Sustainable
Development
Food and Agriculture Organization (FAO) of United Nations
 Supports sustainable development in developing countries through
technical assistance projects.
 FAO projects include sustainable agriculture, sustainable water
management and world fishery production.
 Also pays special attention to women’s roles and inclusion in
development.

Development
International Fund for Agriculture Development (IFAD)
 IFAD mobilizes resources and funds programs designed to help the rural
poor improve their living conditions.
 It promotes social development, income growth, environmental
sustainability and good governance.

Development
United Nations Commission on Sustainable Development (CSD)
 Monitor states compliance and work towards meeting the sustainable
development goals established at UN Conference on Environment and
Development.
 CSD is particularly concerned with the relationship between the
environment and sustainable development and building partnerships
between governments.

Development
United Nations Development Program (UNDP)
 Focus of UNDP is to help countries build and share solutions to what
they have identified as the biggest challenges to the development process
 They aims to protect and promote human rights
 UNDP commissions an annual human development report which is
written by experts who analyse development data, ideas and practices
from around the world with the hope that these reports will draw political
attention to issues and help countries formulate development solutions.

Development
United Nations Division for Sustainable Development (UNDP)
 Works to advise, train and build the institutional capacities of
governments at their own request
 The division designs and implements development projects that the
government subsequently becomes responsible for.
 The goal is to formulate policy around sustainable development.
 Their expertise covers fresh water managemnet, energy, infrastructure
and land management.

Environmental Management
Process by which the environment is developed in a holistic and systematic
manner through the optimal use of existing resources for the ultimate
improvement of human well-being
Successful environmental management includes the following:
 Identification of a type of environmentally harmful activity
 Imposition of specific conditions on that activity
 Prohibition of that activity if it fails to comply the imposed
conditions

Objectives of Environmental Management
To find new and improved ways to conserve the environment
Study the impact of development and application of modern technology on
the environment
Planning for new program to conserve the environment
Implementing compulsory environmental audit for new industries

Environmental Protection Acts in India
Insecticides Act (1986) to protect man and animals from the toxic effects of
insecticides
Wildlife (Protection) Act (1972) to protect wildlife from human activities
Water (Prevention and control of pollution) Act (1974) to maintain water
bodies, rivers, lakes etc.,

Environmental Protection Acts in India
Environmental Protection Act 1986 for the regulation of the environmental
pollution
 They prohibit and restrict the handling of hazardous substances in
different areas
 They provide procedures for the prevention of accidents that may
cause environmental pollution
 They set up remedial measures for such accidents
 They set up standards for the quality of air, water and soil for
different areas and for various purposes

HT MOD I PPT..pptx

More Related Content

Similar to HT MOD I PPT..pptx

More from AlthafMk2

Recently uploaded

HT MOD I PPT..pptx