1. Climatic Zones
Glossary
The weather conditions prevailing in an area in general
or over a long period, typically averaged over 30 years.
Are areas with distinct climates, which occur in
, and can be classified
using different climatic parametres. The
Climate:
Climatic Zones:
east-west direction around the Earth
earth's tilt, rotation
and land/sea distribution affect the global weather patterns we
observe.
Composite climate: hot and dry, warm and
humid and cold climates
Koeppen climate classification:
(A) tropical, (B) Arid, (C) temperate, (D)
continental, and (E) polar.
It displays the chrecteristics of
. The charecterstics change from season to season.
It categorises climate into 5 major
chrecteristics, with each category subdivided depending on seasonal
precipitation and temperature trends.
https://www.britannica.com/science/Koppen-climate-classification
https://content.meteoblue.com/en/meteoscool/general-climate-zones
https://www.ijresm.com/Vol_1_2018/Vol1_Iss10_October18/IJRESM_V1_I10_37.pdf
India's climate comprises of a diverse spectrum of meteorological conditions spread across a broad geographical scale and varying terrain.
According to the Köppen climate classification, , ranging from dry deserts in the west to alpine tundra and
glaciers in the north and humid tropical areas with rain forests in the southwest and island territories.
India has six distinct climatic subtypes
Delhi is situated in the Indian Subcontinent's that are surrounded by land on all sides.
. Delhi enjoys extended and scorching summers, which are
separated into dry summer and humid monsoon seasons, short and fairly cold winters, and two pleasant transition seasons.
Northern Plains Its vicinity to the Himalayas and the Thar Desert
has a massive effect on its climate, causing it to experience both climatic extremitie
The Western Disturbance
and the South-West Winds are the two most prominent wind patterns determining Delhi's climate.
Based on data from 1991-2020

2. Glossary
: The Dry Bulb Temperature refers
to the ambient air temperature. It is called
"Dry Bulb" because the air temperature is
indicated by a thermometer not affected by
the moisture of the air.
https://www.weather.gov/source/zhu/ZHU_Training_Page/definitions/dry_wet_bulb_definition/
dry_wet_bulb.html#:~:text=When%20people%20refer%20to%20the,the%20moisture%20of%20the%20air.
: It is the lowest temperature that
can be reached under current ambient
conditions by the evaporation of water only.
: Is a ratio, expressed in
percent, of the amount of atmospheric
moisture present relative to the amount that
would be present if the air were saturated.
Dry Bulb
Wet bulb
Relative Humidity
https://graphical.weather.gov/definitions/defineRH.html
Max Temperature- 40.2 C ( achieved in June )
Max relative humidity - 89.9% ( achieved in August )
Max Avg relative humidity - 78.8%
Min relative humidity - 22.4% ( achieved in April )
Min Avg Relative Humidity - 38%
Max wind speed - 3.79m/s ( achieved in June )
Max Avg Wind speed - 2.49m/s
Min wind speed - 0.11m/s ( achieved in November )
Min Avg Wind speed - 0.85m/s
Min Temperature- 8.8 C ( achieved in December )
Min Avg Temperature- 13.2 C
Max Avg Temperature - 34.1 C
Source - Andrew Marsh https://drajmarsh.bitbucket.io/weather-data.html
Dew Point
https://www.weather.gov/arx/
why_dewpoint_vs_humidity#:~:text=The%20dew%20point%20is%20the,water%20in%20the%20gas%20form.
: It is the temperature the air
needs to be cooled to (at constant
pressure) in order to achieve a relative
humidity (RH) of 100%. At this point the air
cannot hold more water in the gas form.
Psychrometric chart: presents physical and
thermal properties of moist air in a
graphical form.

3. WIND WHEEL
April-June
In the Summer (early April-end of
june): Extreme heat, low humidity,
hot winds and thunderstorms
Dry
continental winds, called loo
no moisture-laden wind to
increase humidity. The air therefore
remains dry or very dry during day.
are
characteristic of the region.
, at
times blow all across from the West
Asian mainland, making the days
feel hotter. Since the Western
Disturbance depression moves
eastward by this time of the year,
there is
In the Summer (early April-end of
june): Extreme heat, low humidity,
hot winds and thunderstorms
Dry
continental winds, called loo
no moisture-laden wind to
increase humidity. The air therefore
remains dry or very dry during day.
are
characteristic of the region.
, at
times blow all across from the West
Asian mainland, making the days
feel hotter. Since the Western
Disturbance depression moves
eastward by this time of the year,
there is
The Western Disturbance and the
South-West Winds are the two
most prominent wind patterns
determining Delhi's climate.

4. WIND WHEEL
July-Sep
Monsoon ( End of June-Early
October):
South-Western winds
the arrival of moisture
laden ,
traveling from the Arabian Sea
marks the onset of Rainy season in
Delhi.

5. WIND WHEEL
Oct-Nov
Autumn (Post monsoon transition)
(Early October-end of November):
transition season.
changing from South-
Westerly to North-Westerly.
The end of monsoon marks the
arrival of a It is
marked by very dry ambiance,
warm days and pleasant nights.
During Autumn, the wind direction
begins
These are famously known as
retreating monsoon winds.

6. WIND WHEEL
Dec-Feb
Winter (End of November- ):
chilly north-western winds from
the Himalayas
depression created by Western
Disturbance
As
begin sweeping the
Northern Plains, the temperature in
December starts dipping. These
cold waves are caused by a
.

7. WIND WHEEL
Feb-Mar
Spring (Post winter transition):
Delhi’s climate sees another
transition, this time from Winter to
Summer. The transition weather is
known as Spring and is
characterized by warm days, cool
nights, dry ambiance and lively
natural surroundings.Spring rains
are a characteristic of this season.

8. Inferences drawn from the vernacular
The vernacular buildings in delhi features a variety of architectural elements to counter the adverse effects of temperature.
Balconies in front of buildings
to improve cross ventilation
and add sense of openness.
This can be seen in a lot of
historic buildings in Old Delhi.
Sketch of a part of a building in Old Delhi
Chajjas used to protect from high solar radiation all year
round.
Open space in the middle to block out afternoon sun going
into rooms
Louvres of wood used for windows
that are selectively operable and
adaptive
Thick walls of mud or backpacked
bricks having high thermal mass-
storing and radiating heat. By the
virtue of its thickness it helps
modulate indoor temp
Inclines in historic mughal
architecture of Delhi providing
deep shade
Sketch of a haveli in Chandni Chowk

9. Winter Solstice - 22nd December
Summer Solstice - 21st June
Psychometric Charts
A psychrometric chart is a graphical representation of the
psychrometric processes of air. Psychrometric processes include
physical and thermodynamic properties such as dry bulb
temperature, wet bulb temperature, humidity, enthalpy, and air
density.
The comfort zone is defined as the range within occupants are
satisfied with the surrounding thermal conditions. After plotting the
air conditions and overlaying the comfort zone, it becomes possible
to see how passive design strategies can extend the comfort zone.
When data points fall to the right of the comfort zone, you will want
to reduce the air temperature. When data points fall to the left of
the comfort zone, you will want to increase the air temperature.
When relative humidity is too low it can be increased with
evaporative cooling. And when it is too high it can be decreased
with the use of desiccants.
Using the charts we can determine the level of comfort and how to
achieve it either by passive or active methods.
The charts shown here take Givoni Bioclimatic Chart Comfort Model
as shows potential extensions of the comfort zone resulting from
building design characteristics such as solar gains, the use of
internal thermal mass or heating, cooling and ventilation strategies.
Source - Andrew Marsh https://drajmarsh.bitbucket.io/psychro-chart2d.html

10. Geomorphology
Based on Geomorphology types of soil in Delhi can be majorly classified
into:
Khadar
Enriched and formed by fresh deposits of silt every yea
Comprises of silt, clay and sand
Fine in texture, formed bysilt deposit by the course of rive
Clay content varies between 15-17%
Bangar
Older Aluvial soil deposit
Gives a high yield due to high mineral content and humu
These soils are generally fertile with high moisture content but patches
of saline alkaline soil are also found in the area.
Daba
Exist in the lower lying region of Delhi and is mostly sand
Large areas are covered by saline and alkaline soils due to poor drainage.
Koh
Soil is mainly dry and sandy, lacking humus, and supporting sparse
vegetatio
These are composed of quartzites or sandstones of the Delhi ridge
Due to the uneven topography, the soils are subjected to a high rate of
erosion.
Entire area of NCT of Delhi is grouped into three
broad geomorphic units:
Rocky surface (the ‘Ridge’)
The ridge consists of quartzite rocks and extends
from the southeast at Tughlaqabad, near the Bhatti
mines, branching out in places and tapering off in the
north near Wazirabad on the west bank of the river
Yamuna, covering about 35 kilometres. The Ridge
acts as the "green lungs" for the city, and protects
Delhi from the hot winds of the deserts of Rajasthan
to the west.
The Delhi Supergroup comprises quartzite, gritty
quartzite, arkosic grit with thin intercalations of
micaceous schist. The micaceous schist occasionally
contains crystals of garnet, andalusite and staurolite.
Older Alluvial Plain–
gently undulating surface with rolling topography
Flood plains of Yamuna river
Low lying surface.The area immediately south of
Delhi, which includes the Ridge, is rocky and
undulating. This low plateau consists mainly of bare,
unconsolidated rocks. The aerial extent of active
flood plain in NCT Delhi is 97 sq. km. In general,
alluvial flood plain slope is towards south. The
average slope of the Yamuna river bed from north to
south is 0.4 m/km.

11. https://
www.researchgate.netpublication/308180160_Urban_Metabolism_of_River_Yamuna_i
n_the_National_Capital_Territory_of_Delhi_India/figures?lo=1 https://www.researchgate.net/publication/303415221_Groundwater_Environment_in_Delhi_India/figures?lo=1
The area is characterized by very fine textured dendritic
drainage pattern.
The NCT, Delhi can be broadly divided into Six drainage
canal, ultimately discharging into
the river Yamuna –
(i) The Najafgarh Drain is about 39 Km long, flows north-
easterly and joins Yamuna river at Wazirabad in north Delhi.
(ii) Western Yamuna Canal
(iii) Barapulla drain
(iv) Hindon Cut canal
(v) Shahdara Drain
(vi) Agra Canal
A considerable part of the
walled city faces problem of
water logging or is prone to
waterlogging conditions as
depth to water level rests
within 3 m bgl during pre and
post monsoon period. Such
areas generally fall in the
vicinity of river Yamuna,
indicating excessive seepage
from the river.
Old Delhi has one of the
shallowest water table reason
because of its close proximity to
the Yamuna flood basin and low
lying elevation. Water can be
found 5-15 metres below ground
level.
The morphological Ridge area comes under high risk zone;
so, construction of high-rise buildings in the morphological
Ridge area may be dangerous. 10.9% is in the very high
seismic risk zone (Zone-V) while 17.3% of the area falls under
high risk zone (Zone-IV).

12. The SUHII is an important aspect of the modelling of surface energy
balance, urban thermal comfort and climate change at different scales
Surface Urban Heat Island Intensity (SUHII) is conspicuous with the
higher surface temperature in urban areas vis-a-vis contagious rural
areas
LAND USAGE
The changing LU/LC pattern in urban areas also affects theThe changing
LU/LC pattern in urban areas also affects the quality of life in urban areas
by altering its environment, deteriorating air quality and increasing the
frequency of extreme climatic events like high-intensity rainfall,
development of urban heat islands (UHI) and smog-like conditions quality
of life in urban areas by altering its environment, deteriorating air quality
and increasing the frequency of extreme climatic events like high-intensity
rainfall, development of urban heat islands (UHI) and smog-like conditions
The map shows the corelation between land
uage and SUHII
Regions with higher corelation are marked
darker

13. According to studies that studied the compounding
influence of climatic conditions on air pollution, winter
decreased the air quality of both interior and outdoor
air, according to studies that studied the
compounding influence of climatic conditions on air
pollution. They also discovered a link between the
winter weather and an increase in the number of
patients in hospitals with chronic obstructive
pulmonary disease.
Epidemiological evidence together with a better
understanding of the mechanisms that link toxic
substances with the development of diseases,
suggest that exposure to some environmental
pollutants can lead to an increased risk of
developing cancer. Furthermore, several studies
have raised the role of low-dose exposure to
environmental pollutants in cancer progression.
These epidemiological data support the concept
that exposure to air pollution after a lung cancer
diagnosis reduces survival.
Pollution is defined as the
Water pollution, air
pollution, noise pollution, and soil degradation are the most serious types of pollution. Thermal
pollution and radioactive dangers are two less-known types.
contamination of the ecological atmosphere with pollutants that harm
human health, quality of life, or the natural functioning of ecosystems.
Pollution is the term used to describe the effect
of air pollution on respiratory functioning and
the accompanying morbidity in Delhi. It was
shown that the prevalence of
Lower respiratory symptoms
included
, and the incidence of asthma
among Delhi participants was much greater than
in other locations.
respiratory
complaints in Delhi was 1.7 times greater than in
rural regions.
(dry cough, wheezing, shortness of
breath, chest pain)
Vehicle exhaust is responsible for up to 30%
Biomass burning (including seasonal open
fires, cooking, and heating) is responsible for
up to 20%
Industries are responsible for up to 20%
Soil and road dust is responsible for up to
15%
Diesel generators are responsible for up to
15%
Open waste burning is responsible for up to
15%
Power plants are responsible for up to 5%
Outside the urban airshed is responsible for
up to 20%
https://urbanemissions.info/blog-pieces/whats-polluting-delhis-air/

14. STRATEGIES VEGETATION
Evaporative Cooling Privacy
Vertical Gardening Green Edge
Wind Barrier
Roof Gardening
Shading
https://www.researchgate.net/publication/266167918_SHADING_PASSIVE_COOLING_AND_ENERGY_CONSERVATION_IN_BUILDINGS/figures

15. VEGETATION
The vegetation is impacted as a result of the soil condition, which ranges from clayey to coarse sandy from north to south. Quartzites, grits, and schistose rocks
are visible beneath the Southern Ridge's thinner soil cover. As a result, trees with higher water requirements tend to do better on the Northern and Central
Ridges than drought-tolerant trees, which seem to fare better on the Souther
VEGETATION TYPE: XEROPHYTES
A xerophyte is a plant which is able to survive in an environment with little availability of water
Top five tree species in TOF (Urban) in Delhi
Major invasive species in the State of Delhi
Top five tree species in TOF (Rural) in Delhi
SOIL PH :6.75 to 8.4

16. Cooling
Surrounding
context
Whole
building
Rooms
Building
systems
Room
organization
Shared Shading: helps designers
configure buildings to shade each other,
particularly on north-south streets.
Layer of Shades : To reduce high solar load
and make passive cooling possible, external
shading is required.
In a room cooled by stack-ventilation, warm air
rises, exits through openings at the top of the
room, and is replaced by cooler air entering low
in the room.
Interwoven buildings and plants: One can achieve this
by green areas concentrated, such as in parks, and
distributed, such as street trees.
Green Edges: Are patches of irrigated
vegetation formed to cool incoming breezes,
i.e. a bush boundary.
Cooling Effects from Trees and
Colonnades, demonstrates that both trees
and colonnades have an additional cooling
effect that can be added to that of the
urban form effect.
Permeable building: Since humid climates depend
so greatly on ventilation for cooling, it is critical to promote
both cross- and stack-ventilation by making plans
and sections open as a pathway for air.
Buffer zones: Some rooms can withstand changes
in temperature and may be placed between more
sheltered rooms and undesirable heat sources,
such as the eastern or western sun or the roof.
Room facing sun and wind: To support
crossventilation, face inlets towards
the prevailing breezes and be aware of
secondary wind directions
Landscaping
Cooling zones: Specific
zoning to cool certain
areas by use of trees and
other methods.
Vertical gardening Green Roof : Green roofs and earth-berm
walls can reduce or eliminate solar gain
on their surfaces.
Evaporative Cooling Towers: Not very useful in
humid climate, but work well in arid conditions by
using gravity to drive air flow without wind or fans
and to cool and humidify air.
Indoor vegetation - Plants release moisture into
the air through the process of transpiration, which
is when moisture evaporates from the leaves. This
can both cool and warm a room.
Permeable building: A system
of open plans and
fenestrations that allow for
stacks ventilation and cooling.
Night cool mass room: It is useful in arid
climates where temperature ranges tend to
be high. This is a good combination with
evaporative cooling, which can be used to
supplement mass cooling.
Diagrams and images from Sun, Wind and Light by Mark DeKay and G.Z Brown

17. The northeastern part is occupied by the Himalayan tectonic belt as described above whereas; the southern part is occupied by the Proterozoic Delhi fold belt and gneissic-batholithic complex. In the area near Delhi and southward,
outcrops of highly jointed and folded Alwar quartzites are observed. Two tectonic sub-provinces viz. Delhi-Moradabad province and Kasganj-Ujhani province are recognised which are separated from each other along the trace of Moradabad
fault zone.