Climate of lahore and thermal convenience environmental sciences essay

Chapter 2

2.1 Introduction

Climate has great influence on building because of its electricity consumption and setting up performance. Energy efficient design requires the thought of the climate. The overall heating and cooling requirements in the properties is managed by climate during summer time and winter weather. As we’ve selected our web page in Kala Shah Kaku, Punjab and kala shah kaku is definitely located in Lahore region therefore the information of the climatic data of Lahore place is given below.

2.2 Climatic classification:

Climate can be classified in terms building design in which the country will be split into five zones so that the difference of weather from zone to zone can be seen in the building style, gauranting some exceptional provision for every single zone. Based on these requirements, there are five major climatic zones,






Types of climate Usual Characteristics

Cold Excessive heat damage for the majority of the year

Minimum Temperature: below -15 °C

Temperate Excessive temperature lost for component of year

Inadequate heat damage for part of year

Temperature changes: -30 °C to 30 °C

Hot/Dry Overheating for most part of the year

Dry air allow evaporation

Temperature ranges: -10 °C to 45 °C

High radiation

Strong Winds

Hot/Humid Overheating for the majority of year

Humid air inhibits cooling

Temperature often above 20 C

Mean relative humidity around 80 %

High rainfall in certain months

Table 2.1 typical characteristics of various kinds of climates

2.3 Climatic zones of Pakistan:

Pakistan has an array of climatic conditions. The Northern and North- Western elements of Pakistan happen to be cooler, the centre of the Punjab is extremely hot and semi-arid, and the Baluchistan is neat and arid whereas the coastal strip is certainly nice and humid. In cold regions, during the winter temperature drops well below the zero. In the desert regions, the utmost temperature remains above 40°C during most of the summer period; with a peak generally approaching 50°C.The climatic regions have been divided predicated on various criteria.

Fig 2.1 map of climatic zones of Pakistan

2.4 Weather of Lahore Region:

Lahore lies 217 meters above sea level and it lies between 31°15′ and 31°45′ North latitude and 74°1′ and 74°39′ East longitude. On the North and West Lahore is definitely bounded by Sheikhupura district, Wagah surrounds Lahore on east, and on the south of Lahore there can be Kasur District. The river Ravi flows on the North of Lahore. Lahore town includes a total land place of 404km2.

The Lahore area comes beneath the normal composite area, according to climatic zone map. It lies near the hot dry area and in summer months the wind course is in a way that the wind blows northeast towards southwest of the city affecting the environment of Lahore region. The result of hot dry zone starts off from March and continues to be till September as the wind route is southwest which means from hot dry area towards Lahore region. The primary features of this season happen to be that the winds blown are hot and full of dust through the daytime but are cooler in evening. Throughout the day quite strong wind blows. The weather of Lahore region can be divided into the next broad categories:

2.4.1 Warm and dry:

Hot and dry weather is situated in the a few months of March and April. In these a few months the air is dried up with the very clear sky no sea breeze to check the excessive high temperature as the Lahore place is located more than 1000 km from the nearest sea, the heat rise is razor-sharp. In the mid-March the maximum heat range reaches up to 90 F and till the middle of April temperatures reaches up to 100 F. Due to clear sky, nights will be cooler having the average temperature of practically 65 F (18 °C). The rainfall is quite less in this period.

2.4.2 Very hot and dry:

In the weeks of May well and June the weather of Lahore is very hot and dried up and the heat reaches its peak in these weeks. In the second week of Can, the temp reaches up to 110 F (43 °C).Heat is usually oppressive, humidity level is normally low with very hot and dry wind to create loo in local dialect blowing most of enough time. The month of June still continues to be hotter with the heat range sometimes reaching to 119 F (48 °C). Yet, in June due to extreme low pressure produced by the intense heat, sometimes some moisture from Arabian Ocean finds its way to the region and causes rainfall which for the brings the temperature down temporarily.

2.4.3 Sizzling and wet:

The months of July to September are rainy. Monson clouds travel around from the Bay of Bengal and after journeying about 100 km over India reaches Pakistan and enter in Lahore from the South- East. This rain system in these weeks called Monsoons. This is a regular characteristic of the Punjab, in this country. The elements is cool and pleasurable when it rains, usually warm and humid. Although the temperatures decreases significantly, from almost 106 F ( 41 °C ) right before the monsoons starts in Lahore to about 95 F ( 35 °C ) but as the monsoon arrives there is the increase in the relative humidity which boosts from less than 25% to a lot more than 65%. The temperature combined with the excessive humidity makes the elements very exhausting. Moreover oftentimes the rainfall falls with such an avalanche that it drowns the low lying area and people need to undergo great hardships which means this weather is a combined blessing.

2.4.4 Warm and dry:

Warm and dry conditions remains in the weeks of October and November. Because the monsoon how to write an academic paper fast and successfully stops towards the end of September, the elements again becomes dry again but the temperature is considerably fewer hot this time. The dry continental weather remains in the region. The temperature is moderate to warm during days and nights whereas the weather is definitely cooler in nights. The average high temperature is practically 85 F (29 °C) and during the night due to dry air temperatures it could decrease to 53 F (12 °C) especially in the end of October or early on November. There is no rain in this year and this season is the driest season when compared with other seasons. This extreme dryness creates a whole lot of dirt and haziness which results in pollution in the surroundings.

2.4.5 Great and dry:

The most nice months of all will be December January February in Lahore. This is actually the most perfect temperature of Lahore. The peak high temperature is nearly 68 F (20 °C) and the peak low temperatures is almost 41 F (6 °C). The climate remains neat, refreshing and sunny. However sometimes, a rain bearing system referred to as western disturbance which includes its source in MEDITERRANEAN AND BEYOND affects the Lahore location and causes rain. But the rain is

not so serious neither it remains to be for an extended duration. So the weather most of the days remains sunny, dry out and refreshing.

In fact, the weather of Lahore is sizzling and dry for the utmost period of the entire year with a short winter period with very refreshing weather.

2.5 Climatic indicators of Lahore:

The table below displays average monthly environment indicators in Lahore which is based on 8 years of traditional weather readings.

Temperature in: Fahrenheit

Table 2.2 average regular climate indicators in Lahore

2.6 Hot dried up climate:

The hot dry equatorial land lying between the two mean gross annual isotherms of 68°F (20°C) has areas where in fact the temperature during the summer months may reach 43.3°C or may exceed and the vapor pressure is usually below 25millibars.

2.6.1 Elements of hot dry climate:

1 Seasonal variation

2 Air temperature

3 Humidity

4 Precipitation

5 Wind

6 Sky circumstances and solar radiation

7 Dust storm Seasonal variation:

In these regions there are two major months;

hot season


Fig 3.2 Once a month averages of the minimum amount and maximum daily temperatures.

°C/°F Air temperatures:

The main top features of the climate are temperature remains high during the day 80-130°F (26.67-54.44°C) in the summer months along with strong sunshine reflecting pitilessly from light dried up and parched earth.

There is however a huge difference between summertime and winter temperatures because of the varying altitude of sunlight. During winter your day temperature is generally as high as 90°F (32.22°C) but the temperature is very low at nights ,whereas during summer the temperature goes down to 50°F(10°C) weighed against 70F (21.11C) during the night. Humidity:

Humidity remains to be low, Relative humidity varies with the oxygen temperature. It can choose below 20% in evening to over 40% during the night. V.P fairly steady changing with site and season from about 500-1500 N/m2 Precipitation:

The volume of rainfall or precipitation is normally noted as the common mm/working day or mm/month which provides an advantageous indication regarding seasonal changes.

Usually, average maximum rainfall in a day or the average number of days where a certain sum (in cm.) of rainfall occurred can be given. This data is beneficial as an indicator of the rain intensity, that will affect the design of house windows, roofs and sewerage etc.

July and August are the months in which just about all rainfall take place, whereas June and September likewise have some rainy times. For all of those other year, hardly any rain fall occurs in Lahore. Based on temperatures and precipitation info, during the hot and rainy time of year it isn’t advised to move between June and September. The rest of the year is dried out with temperate daytime temperature ranges.

Fig 3.3 Precipitation can be any kind of normal water that falls from the sky within the weather. Sky conditions and solar radiations:

The skies will be without clouds for the almost all of the period of the entire year where as frequent dirt haze and storms appear mostly in the afternoon. Direct solar radiation is serious and is amplified by radiation reflected from the barren and mild colored landscape.

Fig 3.4 Monthly normal amounts of hours of sunshine each day. Wind:

Winds are mostly native; they are generally low in the morning however increasing towards afternoon and are maximum in the afternoon, mostly accompanied by whirlwinds of dust and sand. Dust particles storms:

Dust storms mainly occurs on summer months afternoons which may be the most intolerable portion of the evening , when routine winds blow at 15-220 miles per hour. These dust storms as well occurs in other areas of the day i.e. at night and nights.

2.7 Climatic style of building:

Climate has a great effect on building performance and energy consumption of the building. The process of recognizing, deducing and managing climatic effects at the building is perhaps the most difficult part of creating design. The primary objectives of climatic style of creating should include:

To minimize electricity cost of a building.

To take good thing about maximum of natural energy rather than mechanical system and electric power.

To provide pleasant and healthy and balanced environment for inhabitants.

2.8 Elements affecting climatic design:

The native micro-weather and site factors influence using the environmental circumstances of the building. Some important factors related to site should be included while making the climatic analysis:

Topography- elevation, slopes, hills and valleys, ground area conditions.

Vegetations – height, mass, silhouette, texture, site, growth patterns.

Built forms – close by buildings, surface conditions

Important thermal design elements which should be looked at include: solar heating gain, conduction heat stream and ventilation heat circulation. The design variables in architectural conditions which are essential to be looked at are:

Shape – surface-to-volume ratio; orientation; building elevation.

Building fabric – materials and structure; thermal insulation; surface characteristics; shading and sunshine control.

Fenestration – the size, job and orientation of home windows; window glass materials; external and internal shading devices

Ventilation – air-tightness; outdoor fresh air; cross ventilation and pure ventilation.

2.9 Thermal comfort and ease:

There is no approved regular for thermal comfort. This is simply not astonishing, as persons can and do reside in a variety of climates from the equator to high latitudes. An Internationally- accepted definition of thermal ease, employed by ASHRAE, is "that state of brain which expresses fulfillment with the thermal environment" (ISO7330).

Perceptions of this environment will be influenced by weather temperature, radiant temperature, relative humidity, weather velocity, activity and attire.

Fig 3.5 reaching comfort in buildings

2.9.1 The safe place:

The Comfort Zone means the number of temperature circumstances of air movements, humidity and exposure to immediate radiations, under which a normally clothed person feels relaxed. This will vary for Indoor conditions as compared to Outdoor conditions. This may also vary for different cultures and areas and varying climate circumstances.

As an Architects we make use of our buildings never to only create cozy inside environments, but also aesthetical and useful spaces outside our buildings.

2.9.2 Thermal relaxation index:

A thermal ease index serves the target to evaluate the effect of environmental component on the thermal sense of inhabitants. Amount of methods have already been found in the previously to evaluate the thermal comfort and ease. However it is not possible to gratify everyone in a building and a small number of people are often discontented with the thermal environment due to individual variations. Several work have already been made to create a subjective and quantitative method of representing the thermal comfort.

Thermal comfort state in tropical summer conditions is distributed by Sharma and All at the Central Setting up Study Institute, Roorkee, India. The ranges and optimum values receive in table.

Thermal sensation

Range °C

Optimum value °C

Slightly cool






Slightly warm



Table 3.3: temperature ranges in various thermal zones

2.9.3 Optimal configurations for indoor temperature:

Researchers have carried out much research on the most suitable comfort conditions, and also have come up with general comfort outcomes like powerful warmth, the recent relaxation standards established by ASHRAE (American society of heating system, refrigerating and air state engineers) for a person performing light do the job are:

Thermal comfort conditions:

Air temperature 73-77 F Relative humidity below 60 %

Mean radiant temp equal to air temperature

Air velocity 10-45 ft/min