Oe Climate and Weather Weather refers to the atmospheric conditions (temperature, rainfall, humidity, and pressure) of any place for a short period of time. It is often localized, Climate is a generalization of the day to day weather conditions over a long period of time, usually thirty years Climatic Zones Pakistan's topographical features range from lofty mountains in the north to the coastal plains in the south. The diversity of terrain leads to a variety of climates. Climatic divisions of Pakistan are: A Highland climate B Lowland climate C Coastal climate D Arid climate Fig. 2.1 shows climatic zones of Pakistan. Zone A indicates highland climate prevailing over northern, | 5 en te \ | north-western and western mountains. Zong . has lowland climate, which prevails over th, whole of the Indus Plain. Zone C has coast, climate experienced by the Makran Coag, Karachi Coast and Indus Delta till the Rann Kutch. Zone D has arid climate and includes in, south-eastern desert and the south-western of Balochistan. A division into climatic zones does not exactly the same conditions throughs: tn, zone. There are great variations in ra. ‘a temperature, humidity etc in the same <3) zone. For example, northern highi western highlands fall in the same clima' but the amount and seasonal distr : rainfall is different. Murree and Haz= >) experience more than 1500 mm average ou: rainfall mostly during the summer = scr whereas in the western highlands Que’ = = Pishin receive 250-500 mm avera: rainfall. Winter is the wettest season A Highland Climate This region includes northern, north-western western highlands. The winters are long, cold a snowy and the summers remain short and mit In mountainous areas rainfall is norma associated with altitude. The height of t Northern Mountains range from 2000 metres above 8000 metres, while in the Weste! Mountains the height is approximately from 10! to over 4000 metres. Rainfall in the Northe Mountains is the highest in the highland zo" The Western Mountains experience less rainfé From south of Kohat and Waziristan rainfé decreases and occurs during the winter seas” To the north-west, Gilgit and Chitral also experie” low rainfall, as they are rainshadow areas. The temperature conditions also vary from no! to west depending on the altitude. Summers ? short, mild and wet in the Northern Mount" but dry and warm in the Western Mountains:Lowland Climate (semi-arid to arid) ‘his region includes the whole of the indus Plain except the coastal areas. Most parts of the indus Plain lie at the western end of the tropical monsoon zone. It has arid and extreme climate with hot fummers, cool winters and summer monsoon rainfall. The amount of rainfall differs from north to south. The foothills of the Northern Mountains and Potwar Plateau are wetter than the Indus Plain, and also receive rainfall from Western Depressions ‘Thunderstorms are also common in the north and north-west of the Indus Plain. The southern Upper Indus Plain and the whole of the Lower Indus Plain have much less rainfall and spells of very high temperature. C Coastal Climate This region includes the southern coastal strip comprising of the Indus Delta, Karachi and the whole of the Makran coast. The climate is dominated by sea breezes throughout the year. The maritime influence keeps the daily range of temperature low. Maritime or coastal climate is explained in Fig. 2.2. This shows that the influence of sea is felt mainly through the prevailing winds. The temperature at sea and on land is different owing to unequal heating ofland and water by the sun. Land and water absorb the sun's heat at different rates, and also radiate or lose it,at different speeds. In summer the land heats up, while the ocean remains comparatively Pe ete act ent eer Regie sees ae cool. In winter the land loses heat quickly and becomes cold while the ocean is much warmer and keeps its warmth for a long time. The humidity level is moderately high, exceeding more than 50% from April to September. Mean monthly temperature is 32°C, and May, June and October are the hottest months. During October dry winds from the south-eastern desert dominate the climate. Rainfall is scanty throughout the yezr. From Karachi up to the Rann of Kutch, the coast, experiences most of its rainfall during the monsoon season, while on the Makran coast it falls in winter. D Arid Climate ‘An arid climate is experienced in south-western Balochistan and the south-eastern desert. It is markedly dry and hot. Hot dusty winds prevail almost continuously from mid-May to mid— September. Most of the scanty rainfall in south- western Balochistan takes place during the winter season. In the south-eastern desert, summer Winter Early Summer Late Summer (Monsoon) Post Monsoon _Ma-December to March April to June July to September October to Mid December poner FETE | gaan memes | agp toit Co ‘Karachi experiences high spells of heat | Formation of stratus clouds lowers the | Temperature rises in October and drops ‘(AZ C) when winds from the Rajasthan | temperature, | lin November, December and generat _desert blow to the south-west, _deynees prevail. Se atten | SARS RTRER Ger sc Seca amare | sa | = | sgt Sata ‘sing fermen tet” | Panic 2 oie | ro sgarattecnter rte Saaz | in western highlands | Plateau,monsoons bring little rainfall. Extreme heat, dryness and dust storms are the main features of this arid climate. Pakistan: the Seasons Pakistan has four seasons that can be distinguished as follows: Winter (mid-December to March); early summer (April to June); late summer (monsoon) (July to September); post monsoon (October to Mid December). The table Fig. 2.3 explains the temperature, rainfall and pressure conditions that normally prevail in Pakistan with reference to some particular areas. Climatic Elements ‘There are four main climatic elements - temperature, pressure, rainfall and winds. These are responsible for the regional and seasonal variations in the climates of Pakistan. Temperature Diversity of temperature in various regions is due to the following factors: January Temperature ly © Large spread of latitude from 24°N to 37°h, © Diversity of relief ranging from the very hig, mountains (up to 8610 metres) in the north, low lying coastal areas in the south. Temperature 40° C and above 31°C 39°C 21°C -30°C 10°C - 20°C sCo-9°C 0-26 Below -6°C The upper and lower Indus Plains heat up during the summer making the daily maximum temperatures rise up to 40° 45°C which is very hot. Jacobabad, located in the lower Indus Plain, is known as the ‘thermal pole’ of the ‘sub-continent where the [sure Temperature i Description Very hot Hot Warm Mita Coot Cols Very cold Fig. 25 is nhly temperature in most sreas of Paki ee cen Oa roan eC nny rate akistan temperaturemaximum temperature reachos, §3°C in June, and Tre mean monthly maximum tomperature reaches yc in May and June (Fig. 2.5) wire | 0 [x wah tn, ase a ea a Fa oe ee ee bee =. he ten 7 rea = ‘oa, [ema [ww ercon [eget ona (ree an Balochistan] et Ea summer | en] ont oc, - | High angle of sun. nr tga Teams [var [enone [pa cle conn ott [Sukie ae High angie of sun. Coxon ramen [er [ama ier Semele sige summer | emt Coastal areas have moderate temperature during summer and winter. Sea breezes dominate the climate lowering the daily range of temperature. Factors affecting temperature of Pakistan Latitudinal effect: The areas closer to the Equator receive relatively direct rays of the sun resulting in high temperature. Southern Pakistan is closer to the Equator than Northern Pakistan. Continental effect: It is a general term covering the climate of those areas protected from or unaffected by maritime influence. Maritime influence means the influence of the sea on temperatures. Along coastal areas, ocean currents and prevailing winds usually have a moderating effect on temperature. This is why extreme winter and summer temperatures are recorded in the interior of large landmasses away from the moderating influence of sea Altitude and temperature There is a relationship between altitude, air density and temperature. The air is densest at sea level because that is where it absorbs most water vapour, dust particles and solar radiation. Air is least dense at high altitude because less solar radiation is absorbed at that level. With less air to absorb heat at higher altitude, there is an average drop of 6.5° C in temperature for each 1000 metre increase in altitude. Cloud cover and temperature Cloud cover affects temperature to some extent. In the daytime it reduces the amount of incoming solar radiation by reflecting it back into outer space, resulting in a drop in day temperatures. At night the cloud cover traps the outgoing heat As a result, temperature on a cloudy night does not drop as low as temperature on a clear night. Latitude and the angle of the sun The term ‘angle of the sun’ refers to the position of the Earth in relation to the sun. The diagram shows that the sun's rays do not fall at the same angle everywhere on the Earth's surface Latitudinal position determines the amount of heat received by the Earth. For example, compared with the sun's rays that fall nearer or at the Equator (i.e. from C- D), the sun's rays falling near the North and South Poles have to heat a larger surface area (i.e. from A -B) andtravel further through the atmosphere, and have loss heating effect. Similarly the difference in the heat received in summer and winter is due to the difference in the angle of sun. During summer, the northern hemisphere (Pakistan is located in the northern hemisphere north of the Tropic of Cancer) is tilted towards the sun and therefore the land absorbs more heat because a) of the high angle of the sun and b) it faces the sun for longer duration (longer days and shorter nights). During winter, the northern hemisphere is tilted away from the sun (i.e. a low angle of the sun) so the earth absorbs less heat and faces the ‘sun for shorter duration (shorter days and longer nights). ‘Low angle ofthe sun: longer distance through the atmosphere covered by sun's rays (AB) at higher latitudes Rainfall Fig. 2.9. shows that most of the areas of Pakista, are arid or semi-arid. Only in a few northern araa, humid conditions are found. The rainfall as a w oj decreases from the Himalayas towards the ©: Sources of Rainfall in Pakistan Monsoon winds The Western Depressions Convectional currents causing thunders ys Relief rainfall Tropical Cyclones The Monsoon Winds ‘The word monsoon means a season. These \ ng are seasonal which blow during summer and v te The summer winds are called South-west mons .or and the winter winds are called North-east monsicr. South-west monsoons are giant sea breezes, whic bring heavy rainfall. The rains begin when surim: sun heats up in tropical continents much faster the the oceans around. Warm air rising overiand cr a low pressure, which attracts cool, moist air fro the’sea, and rain-bearing winds gradually push: farther inland causing heavy rainfall North-east monsoons blow from the land towart the sea. During winter a high-pressure area created over the Tropic of Cancer. Winds blow tre” land to sea, which is a low-pressure area These winds are mostly dry and bring no significa’ Inge because they originate in a dry area ‘Atooded roa B heavy shen ei989 Tad transpo anata ‘Shower of monsoon ranria neysign 1 aha‘The map Fig. 2.11b shows that the main monsoor Jinds blow from the Bay of Bengal. After crossing Sangladesh_and North India, the tail end of the ‘wand enters northern Pakistan, The winds normally Start to blow in June and cause heavy rainfall in northern Punjab in July. The graph for Lahore Fig. 2.12 shows that the mean rainfall in both July and August is 125 mm. September is the end of the monsoon season. September is the end The map Fig. 2.11b shows that some monsoon winds blow across south-east Pakistan from the ‘Arabian Sea. These are weak winds and have little ‘effect. However, sometimes an over-active monsoon system bring heavy monsoon rainfall in Karachi and coastal areas of Sindh damaging the infrastructure of the region. — JANUARY [LY ‘0 F= Monsoon winds are seasonally reversed and driven by temperature differences between land and sea. © They blow toward the heart of the continent (land areas) in summer. © They blow toward the sea in winter. ‘The graph for Karachi (Fig. 2.13). shows that the total rainfall in July, August and September is considerably lower than that in Lahore. Western Depressions Western Depressions are the cyclones which originate in the Mediterranean Sea, travel across Afghanistan and Iran then reach the western areas of Pakistan. After striking the north-western areas such as Peshawar and northern Pakistan the winds move towards western and south-western parts By the time they reach to south-western BalochistanAdvantages © Rainfall in light showers- absorbed by the soll increases moisture contents of soil and helps to prevent soil erosion. © Provides water to rivers and reservoirs that can be used for irrigation. © Supplies water for HEP generation. ‘© Barani crops in northern Pakistan depend on winter rainfall ‘© Provides water for Rabi crops such as wheat, barley, oilseeds and pulses. ‘© Snowiall forms the glaciers in Karakoram, Hindu Kush and Himalaya mountains that feed the Indus System. ‘© Snowfall in northern areas attracts tourists. Disadvantages ‘© Crop planning becomes difficult because of the difference in amount every year. ‘© If rainfall is low, crop cultivation is not possible difficult on barani farms. ‘© Snowfall lowers the temperature in northern making cultivation impossible @ Causes damage to the environment inthe fo landslides, avalanches etc, ‘© Transport links get blocked due to accumu snow. ‘© Covers the grazing lands with snow in extre ox thus forcing farmers to practise transhum: ‘© Health problem such as frost bites, asthm infections and other respiratory problems in highland areas, A Monsoon Experience 1 got out at around 7:30 am this morning and found everything dark, wet and dangerous. It was raining so hard and visibility was so poor that I had to turn, on the headlights of my car. All the roads had become raging torrents and even the main highway looked like a swollen river. The rain submerged streets all over the city in just 25 minutes. The short burst of heavy rainfall was accompanied by a strong wind, having a velocity of 50-60km per hour. When I reached my office, I came to know from my colleagues that the meteorological office recorded 57mm at the airport. I needed not to switch on my AC as the rain and cloudy weather reduced the maximum temperature from 35.3 degrees Celsius to 27.2 degrees C. The minimum temperature was 23.8 degrees C with 85 per cent humidity in the morning. assumed that this weather pattern would continue for another 48 hours, though the system would gradually lose its strength. My office had a deserted look as few people had been able to reach it. Late arrivals at offices and power disruptions affected work a great deal and business activity, too, slowed down trade in markets mainly because of the inundation of roads around them. It was risky to stay in office if the same weather persisted. I tried to contact my family but telephone lines were not working, Looking at the situation, | decided to go back home. On my way back, my car got stuck in a depression filled with rainwater and leakage from the sewage pipes. All other vehicles were floating on the road giving off heavy smoke from their worn out engines. The rain had damaged the infrastructure t extent adding more miseries to the lives of ey ete: Doers tha eka on food Fran For the next 24 hours, the whole city life came to! halt It was announced on radio and TV that tra will be delayed and air flights had been cancellet All educational institutions would be closed and the monsoon rainfall continues, an emergency wou! be declared. The fishing communities were asked! stay away from the wild sea as a precautions! measure. ‘The heavy rainfall in northern Punjab particularly the hilly tracks may result in flooding in Sialkot regi which is located at the foothills of the Northe" Mountains, destroying the crops. Looking on the bright side, at least the recent watt shortages would be over. The level of the Man and Tarbela Dams is also expected to rise due! Continuous heavy rainfalls, I hope that WAPDA ¥! heave a sigh of relief as there will be no electri! Crisis in the coming months and more irrigation W"” would be available for the crops.they are robbed of their moisture. These winds cause the rainfall in these areas from December to March. For example, Quetta receives most of its rainfall during the winter seasons. (Fig. 2.15), —<—<—<—<$<$<——_ ive owt omg °C ‘Mean Monthy emperatre n° ‘QuETTA a s [enn a = a ” = = — | Sia eee le = = « 5 0 oer Fie 218 Convectional Currents ‘Atthe start of summer, hot air rises up which also contains a high moisture content. When it reaches the higher layers of the atmosphere, condensation takes place (Fig. 2.16.) This causes rainfall, often as thunderstorms. Strong winds accompanying the storms may pick up dust as well. * 20 “ |S = [rtinan x ie = | RNS I a aay | = ¢ Only the northern and north-western areas of Pakistan receive rainfall from convectional currents. ‘Southern Pakistan is deprived of convectional rainfall due to a temperature inversion layer. Look at the temperature and rainfall graphs (Figs 2.17 anc 2.18) for Rawalpindi and Peshawar. These area receive some rainfall in early summer caused convectional currents. 1001 (wins segues a ry ohn Feseaton sone + arm a ave Fig. 249 Temperature inversion layer to the south of Pakistan does tel duo corvocbonal rata too lac Saat temperatures. Ge Fig. 2.19. shows that a temperature inversion layer does not allow condensation to take place at the height of 1600 m. As a result warm air descends and no rainfall occurs. That is why Karachi and adjoining areas do not receive convectional rainfall although the maximum daily temperature crosses 40°C in the month of May/June and October. Relief Rainfall Relief rainfall is related to the height of land. It ocours where moist unstable air moves up a mountain or scarp edge, and it is chilled. This chilling causes heavy condensation and precipitation, on the windward side. The lee slopes tend to receive sinking, warming air, and a dry ‘rain shadow’ area may lie leeward of the barrier. This is shown in Fig. 2.20.e RELIEF RAIN Condensation lovel Mantis exporencnd in ost fhe igh ae Fg. 220 oll nln arp orth vsnadon aes ihe a hen oe nt ore an 25. Preciaion nor of Sromintign ose seas “The photograph shows the landscape of Chiral whichis a rann Shadow area, Arange of barren mountains and plated {rnatural vegetation can be Seen inthe valley areas. [Rese ey ape —| ‘Poza 'n the north and north-western area where there is high altitude, ‘some of the raint ale. asons due to high tioned. —4w ee | Tropical Cyclones Tropical cyclones may bring a few hours of very heavy rainfall with destructive winds to the coastal areas. They originate over the Arabian Sea quite often but only rarely do they reach the coast of Pakistan, usually once every few years. Therefore this source of rainfall is totally unreliable both in terms of when and where on the coast it will occur. (See also page 43-44). Pressure and Winds During the summer season, the temperature in central Pakistan is high. This causes the hot air to rise up and form a low-pressure zone. At the same time oceans and seas have comparatively low temperature. This is because water absorbs and discharges heat slowly as compared to the land. The air pressure over the oceans and seas is higher than over the land during summer. This leads to the movements of monsoon winds from sea to land, which are moisture-laden and bring heavy rainfall to the upper and lower Indus Plain in the months of July and August. ‘ear rotates, seinen ar bee oe SEA ee meetClimatic Zones. © Relief rainfal Monsoon rain! © Thunderstorms + Western Deprossic 4. Highland zone © Convectionalrainisi Punjab Western Doprossion Punjab ‘© Monsoon rainta 2- Lowland zone | « Fig, 224 Norhem and westom areas of Pakistan receive rainfall ung winter season (January) due lo Wester Depressions, [Fic 2.28 os of te areas iocatd oto noth and easier side of Patan receve ania rom mongoon wind Ju During winter the whole situation is reversed because the pressure over the land gradually increases and a high-pressure area is created in the north-west of Pakistan. The summer monsoons gradually retreat in autumn and are replaced by land winds blowing out from the high-pressure area. These winds are called the winter monsoon or the north-east monsoon. Fig. 2.11a shows the direction of winds from land to sea. These winds are generally light and dry. | Monsoon rainfall (Sinch coast) Wester Depressions (Makran coast) © Tropical cyclones {Little ralnfall from Monsoon winds ‘and Western Depressions. Fig, 228 Sources of Rainfall in Cimatic Zones Effectiveness of Rainfall The rainfall in Pakistan is mainly from monsoon winds and Western Depressions. The monsoon winds bring rainfall during the summer season, which is variable in amount, timings and distribution. That is why the effectiveness of monsoon rainfall is of limited value to agriculture. Another factor that limits the usefulness of rainfall is high temperature conditions from June to September over the Indus Plain. This leads to a great degree of evapo- transpiration. Monsoon rainfall comes in heavy showers, which is not very useful for the crops, because the land does not absorb the rainwater. Most of the water from the monsoon rainfall drains away causing floods in the low-lying areas. However, reservoirs of the dams on River Indus and its tributaries help to store extra water during the rainy season that can later be utilized in the dry season. The variable nature of monsoon rainfall also lessens its usefulness for the farmers. Crop planning is very difficult if the amount and timings of rainfall have above normal fluctuations. Only a tiny fraction of the Potwar Plateau has canal irrigation. For the rest, it is ‘barani land” because of impracticability of lifting irrigation water up to the flat plateau surface and also of irrigating the heavily eroded badland areas. The winter rainfall is more effective for farmers because it comes in light showers that continue for several days. However, the amount of winter rainfall is not sufficient and cannot be relied upon.Factors accounting for climatic variations Pakistan's topographical features range from lofty mountains in the north, to the coastal plains in the south. This diversity of terrain leads to marked differences in the climate of different regions. © Generally high temperature due to latitudinal effect. © Relief rainfall in the Northern and the Western Mountains due to high altitude. © Monsoon winds system brings summer rainfall to the Indus Plain and northern areas, ‘© Coastal areas have maritime climate, i.e. low temperature range and high level of humidity. Winds from the Arabian Sea keep temperature comparatively low during summer and high during winter. 7 © Western Depressions that originate in the Mediterranean Sea bring rainfall to the western areas of Pakistan during winter. © Convectional currents bring rainfall to the northern Punjab and KP in the months of May and June. © Central Pakistan enjoys high temperature due to continental effect. © Convectional rainfall does not take place in the south of Pakistan during summer, due to temperature inversion layer. © Tropical cyclones from the Arabian Sea occasionally bring destructive, strong winds and heavy rainfall to the coastal areas, > See eats sl {only occurs in the western and northern region. Coastal and southern Pakistan have to depend upon monsoon rainfall Generally, the rainfall in Pakistan is neither lependable nor enough in quai ont igh in quantity. As a result ly depends on the irrigation However, in nrtnem Punjab ora Rotor een, (being wetter than the rest of Pakistan) there are 2 number of ‘rainfed’ or ‘barani’ farms where Subsistence farming is practised. It is not possible to develop canal irrigation in the Plateau region, Effects of Climate on Life ad Economic Activities of Peop e in Different Regions Climate influences the lifestyle, economic activi +s and temperament of people to a great extent. Pakis in has a diversity of climate due to differences in phys al landscape. Highland Zone Severely cold winters and mild to warm summers characterise the climate in northern and north- westem areas of the highland zone. In the northern areas the temperature falls below freezing point. The growth of trees is retarded, the grass is buried under snow and at some places rivers and torrents also freeze During winter farming is not possible. People are involved in indoor activities like carpet weaving embroidery work, pottery etc. Transhumance is also practised i.e. moving the flocks up to the cooler highland in summer and returning to the plain areas in the cold winter. The barren hills of the Khyber Pakhtunkhwa are sparsely populated. Most of the Pathan tribes still live as nomadic herdsmen, keeping goats and sheep. Due to extremely low temperatures during winter, they have to move to lowland areas with their animals. The Vale of Peshawar is the greenest part of this region with extensive woodlands, orchards and irrigated fields. Fig. 227 Heavy snowell nh ‘Sor (Hie see foreland wees» P00 gat | In the extreme north due to landslides ai transport links, Job Many areas are not accessible nd heavy snowfall hamperind ©pportunities are also limitedin this region and economic activities are difficult to carry out. As you move towards the south, temperature increases in both summer and winter. The Western Highlands and barren mountains of Balochistan are also sparsely populated due to harsh physical conditions. Annual rainfall is 125 - 250 mm in most of the areas and occurs mainly during winter. Lack of water supply discourages human settlements. Crop cultivation is also difficult in these areas However, apples, mangoes, apricots and grapes are grown in the valleys of high altitude areas. Pas rs BES In ghland areas te a common practice to meve animals [fit 228 Sranecessarybelongign to owned areas Gung winter Arid Zone This zone occurs in two parts; the south eastern deserts and the Kharan Desert (including the Chagai Hills). The climate is one of extremes; with low annual rainfall, cool-mild winters and hot summers. Summers are very hot during daytime. ‘A region so deficient in moisture and so extreme in its temperature cannot be ideal for habitation or Cultivation. The majority of the people are nomadic and belong to such groups as the Brahuis, Balochis ‘and Pathans, They move with their animals in search of food and water. Due to scanty rainfall and excessive evapo-transpiration, a unique system of underground irrigation ‘Karez" - is practised. Karez 's a narrow sub-terranean canal, which starts from the base of the hills and mountains where subsoil \water is present. After coming to the surface, Karez irrigates the orchards and agricultural fields many of which are sheltered by date palms. This indigenous method prevents the water from being evaporated by the heat of the sun or absorbed by {he thirsty land. The highland areas of Balochistan with cold and dry climate and winter rains due to depressions, are suitable for the growing of fruits (grapes, apples, peaches and melons). Other crops include millet, wheat, and barley. Fig. 2.28. in lower Sindh, the carl is widely used 9s transport bythe local poople because ican retarn water for Several cays, An iigated eld and afew trees can be seen | inthe background, In terms of rainfall desert covers almost the whole of Sindh and the southern part of Punjab. The area receives only 100mm of annual rainfall and the average monthly temperatures in summer rise to over 38°C. Under such extreme heat and low Precipitation, crop cultivation is very difficult. However large areas have been reclaimed for farming through the construction of perennial canals enabling the irrigation of the western part of southern Punjab and a wide strip either side of the Indus in Sindh. In those areas rice, wheat, cotton and oilseeds are cultivated. The remaining areas of the Thar desert are still barren desert. The lifestyle of the people is also affected by the climate. They wear thick and rough clothes to protect themselves from hot winds and also wear turbans. They move from place to place in search of water for themselves and their cattle. Lowland Zone - Semi-arid to Arid The fertile plain of Punjab, drained by the Indus and its four tributaries has a continental or extreme \ype of climate. itis because of the northerly position of Punjab Plain, In the daytime summers are extremely hat. Winters are coo! to mild Economically, the Punjab Plain is the most productive agricultural region of Pakistan. In view of the generally varied and irregular rainfall; there is a well-developed canal irrigation system to raise crops like wheat, millet, cotton and sugarcane.The Thar Desert isa water deficient area and it can be reclaimed by constructing seasonal/flood canals from the Sukkur Barrage to increase production of food. The Thar Desert is rich in mineral resources such as coal and oil. Itis more feasible to invest in the setting up of coal-fired thermal power plants than to use the land for farming. Which statement do you agree with more? Give reasons for your answer and refer to places or examples you have studied in Pakistan to support your answer. shows a ractonal hous n Thar Desert "one. Duo to extremely ow rafal oe Noh lenpertr, nt aad wn reac The sal urls Have boon fly covered io paven Se evaporation esos, Md wate and sary thatched oo Keep te fooms col witout fons or conciioers Punjab is the most densely populated province of Pakistan because of its alluvial plains, moderate ‘rainfall and tolerable summer and winter temperatures. (Climate direc afects the sive of contrac or example, in Tharparkar vec Go ton of house sormampl Marpac which &panony ht re oon bull with xed vont 5 iy breeze tha Blows fom the wh Life and Economy in Thar Des« t; A case study The Thar Desert is located to the south:€2.. of Pakistan. It is a dry si of about ? 09 square kilometres, of which about 1/5 is cultiv +4. Crops of guar, millet, mung bean, kidney | in, sesame, water melons and castor seeds are |) vn, on about 4/5 of this cultivated land and fodder py on the remainder. The agriculture depends on fal, except in a few canal irrigated areas in the wc ‘The cash crops like chillies, onion, garlic, brinj: ng wheat are grown by using well water in the ‘ith ‘The soil is sandy but also contains fine partic so clay and silt which make it fertile. The rain is co! ted in the traditional style in ponds and tanks anv als by building mud bunds on small temporary riv sto hold up the flow. Rainfall is the only source o* iresh surface and groundwater. The low rainfall occur during the monsoon season from July to September ina few, scattered but heavy showers. The irregular rainfall periods are followed by long spells of drought The high temperatures result in a high rate o evaporation. More water is evaporated than i supplied by the rainfall thus the land remains dy and little water seeps underground. The land suffers a lot on account of drought which may last from 3 to 5 years, The results are scarcity of water, food shortages, Poverty posing risks to life, danger to the livestock.~llthese factors result in a decline in the economic activity of the people. ‘The peasants and farmers of Thar prepare their lands and grow local crops and green fodder fot animals, ‘which are reared in this dry region. The desert lets, natural vegetation flourish after rains .This includes hherbs, shrubs, grasses and pastures, which helps boost the Thar economy and also provide food, feed ‘and fuel for the local population. The locals rely on these resources rather than seeking aid from the funding agencies. The rains increase the opportunities to produce more food by growing cereals. There is ample production of milk, butter and meat from domestic animals and livestock during the rainy season. Problems in the Thar Desert are varied as listed above. The water shortage in terms of crop cultivation and for drinking purposes is a chronic one. The sandy soils do not hold water for long periods. Thus farmers start preparing their lands to sow seeds either before or soon after the rainfall, in order to take advantage of the moisture in the soil before it evaporates. Before the onset of rains, the farmers make bunds, dig pits and go for village practices of retaining the rainwater in sandy soils for crop cultivation. The ‘water thus is collected into man-made ditches and | natural hollows, ‘The rainwater may also be stored in earthen jars. household utensils, overhead as well as underground ‘cemented tanks. It is also stored on the roots of "Pucca" houses with solid borders. The capacity of such water containers and reservoirs is not enough to meet the drinking water needs of the population living in the area. But ample quantity of rainfall during a particular season may saturate the deeper layers of the soil, thus recharging the subsoil and raise the underground level of sweet water and also recharge wells dug in the area What of the Future? The establishment of tree plantations and the construction of a seasonal canal from the Sukkur Barrage to bring flood water would increase the Production of food crops and help to bring prosperity to the area. More rainfall needs to be collected to provide drinking water for humans and animals and an increase in the grass and greenery in the desert might also attract some tourists. | Coastal Zone Pakistan has a delta coastline in Sindh and the hilly Makran coast in Balochistan. Karachi Thatta and Badin are important centres on the Sindh coast and Gwadar, Ormara and Pasni are located on the Makran coast. Karachi has a mild climate with a low a precipitation (approximately 250 mm per the bulk of which occurs during the J monsoon season. Winters are mild and \ are hot. However, the proximity to the sea humidity at a high level (60%-70%) a breezes relieve the heat of the summer The winter months (November to Febr generally considered the best times to visit «. when most of the social events take place. Tourists and expatriates visit Karachi in these months The climate of the Makran Coast is dry and hot. The maximum temperature in June remains between 31°C and 40°C and in the coolest month of January it varies from 18°C to 19°C. The oceanic influence keeps the temperature lower than the inland areas in summer and higher in winter. Humidity prevails all along the coast and average annual rainfall is below 250 mm The extent of precipitation affects the supply of drinking water in Gwadar district as most of it is provided from reservoirs which are rain-dependent. The moderate climate was one of the important factors in the development of Gwadar port as it would make it operational throughout the year for trade activities.Due to the mild climate of the Sindh coast, economic activities can be carried on throughout the year. Farming is possible almost throughout the year depending on the availability of water from irrigation channels. The seaports are open all the year round to carry out international trade. Road and rail transport links to inland areas are never closed for business and economic activities. Air flights are rarely cancelled due to climatic reasons. All types of industries ranging from cottage and small-scale to large-scale manufacturing are operational in all seasons. However, during summer months, tropical cyclones sometimes cause coastal flooding in low-lying areas causing damage to infrastructure, shanty homes and farming land of the Indus Delta. Fishing is nearly impossible when the sea is wild. Thus fishing communities suffer economic losses due to tropical cyclones. Fig. 234 Avopcl cyclone nt conto Pakistan in une 2007, | damaging shorty homes sed agra as, eopl,cutng ro inte ng doors a hove. i Mubarak vlogs Some 59 tm mn Kare, River Floods Rivers provide an attraction for human settle ‘and economic development. Water is a vital eas {0 People for drinking, washing, industrial processes, leisure, agriculture and transport. However, excessive water in the rivers may cause floods. The Indus and its tributaries swell, and almost every year overflow their banks. The flood in most years 's not serious. However every 7 ~ 8 years there are ‘Severe floods. Serious floods occurred in 1955, ‘Tho photograph shows foo sected fomonn salor place slong win ther vestock armas a Satongings, Fig. 2.38. Floods in 2010 dovasiated large lande 1973 and 1978. In the 80s and 90s serious ‘loot; also occurred causing large-scale devastation, In 1955 a flood inundated 2420 villages; 400 peop and 70,000 cattle lost their lives. The Ravi Syph (a canal to release water to the fields) wa destroyed. The total damage caused by flood: amounted to Rs. 83 million. In 1973, floods inundated 3.6 million hectares, Kile: 1600 persons and demolished three million home: Meting ot snow dicing summer. made worse Oy arta [Pa 2, Ss tna weary garthwhat Can be Done to Reduce the Flood Risk? preventative and curative measures: ‘e Planting trees on the foothills to check the flow of running water. e Enlarging the river channel so that it can hold more water. ‘e Building embankments on either side of the channel to prevent the spread of floodwater. ‘© Building extra channels to take floodwater away from towns © Building reservoirs on the river to store water and control peak discharge. ‘© Preventing building in areas where flooding is most likely. © Publicizing flood warnings through radio, television and newspapers. © Evacuation of flooded areas and providing necessary facilities for rehabilitation. Group Precautions During the Mongoon Ini hewmterhes” | precious baenginge Foul be moved to |2-the nd te ver] Riger pac Farmer "The houses willbe | Local elders shoul be Tat trom shops | moved tonigher sree indservices."-'", | slong win har precious Local _|2.Modhouees and huts | Belonging. Residents Alternative san {orth basic no ofite, Transport uch aa pons Authorities Rapa ofthe roads ane alleay tracks should be ‘done 3a on emergency, Beate [Fig: 237, The effects of fooding on alfrent people. Benefits of Floods Although flooding can be devastating to an unprepared community, it is a natural event with a purpose. © Floods return nutrients to the land and contribut to the health of wetlands as in the Indus delta Wetlands allow floods to spread over a area and cause little or no damage. @ Floods distribute rich sediment and + streams. Floods spread a layer of alluvium increases the fertility of the land. A flooded can be used for rice cultivation. Over the cent farmers in the Indus Plains have made selection of the most appropriate rice varieti to enable them to face the seasonal floods. ©. Allowing rivers and streams to overflow their banks naturally can prevent more serious flooding downstream. © The relatively high level of fish production in the Arabian Sea is attributed to the nutrient rich delta of the Indus river system. © The reproduction, breeding and multiplication of inland fresh water fish and prawn species is finely tuned and adjusted to the monsoon flooding. © Floods also recharge ground water supplies. Fig. 2.39 Flood in River Indus. Storms Thunderstorms are common in the northern and north-western areas of Pakistan. In the summer (April to June) and the post-monsoon season (Sept- Oct), the atmospheric pressure falls and convectional currents cause sporadic and localized rainfall in the extreme north and the Safed Koh Mountains. This is accompanied by strong winds from 60 ~ 80 km per hour. Stormy rainfall and hail also occur as @ result of these winds, which cause the destruction of apples, pears and other crops grown there,set SSS “6.000 missin Seven killed, hundreds Delay in’ rr 0 200 = as cyclone = hits Sindh = =~. $eoastal areas =~ eS Ss In the summer season, in southern plains and north-western parts of Balochistan, due to low Pressure, dust storms and strong winds are also experienced. Sometimes, such dust storms also hit the upper Indus Plain and, like floods, damage crops and orchards. When the windstorm is of high intensity, the roofs of the houses are badly affected, Electricity and the communication system also get disturbed. However, storms are less frequent than floods and usually localized. Tropical cyclones from the Arabian Sea can also affect the coastal areas of Sindh and Balochistan. In May 1999, a tropical cyclone ‘2A’ hit the coastal areas of Sindh, causing wide-spread damage to the people and their belongings. The destruction caused by storms increases if relief teams are either delayed or do not reach at all There is a dire need that all the coastal areas should have proper arrangement including flood monitoring cells, proper warning systems and relief teams to handle such calamities. Drought in Pakistan Drought is @ hazard of nature and one that «in present a very big threat to those who live off \¢ land. Lack of rainfall results in severe w 3: shortages, which can destroy crops. In the wo poor countries drought brings famine, disease death on a massive scale. Types of Drought There are four different ways of categorizing drought. @ Permanent drought exists when crop cultiy >. is not possible without irrigation e.g. al Cholistan, Chagai (Western Balochistan) © Seasonal drought occurs in areas with defined rainy and dry seasons. e.g Pc va Plateau, southern Punjab ¢ Invisible drought is the result of a vate deficiency that reduces crop yields but is o0 severe enough to destroy them © Unpredictable drought is the result 0 abnormally low rainfall and occurs in areas whict have humid climates. Causes of Drought in Pakistan Natural Factors that can lead to drought in Pakistan are: © Unreliability of monsoon winds may lead to seasonal drought in Punjab and Sindh, © The dry and hot winds can reduce the moisture Contents of sandy soil by lowering the level of humidity in the ar. © Global climate is constantly changing leading to changes in Pakistan's climate. Human Factors that may | conditions in Pakistan are: © Deforestation on the foothills of mountains increases soil erosion and reduces rainfall * Mismanagement of water resources through seepage of unlined canals ete. © The disputed and unfair distribution of water between the provinces may lead to a drought situation in the province which is deprived of is fair share of water © Overgrazing of land, leading to soil erosion thus reducing soil fetity, * Global warming leading to climate changes. {70.241 Cavees of Oouphtin Paks, \d to droughtHow 2000 - 01 Drought Affected Pakistan physi: environment In Pakistan permanent and seasonal droughts aff the life and economy of the desert areas of S and Balochistan to a great extent. In 2001 the 2 districts of Balochistan suffered from severe (ay as a result of drought. Out of these 26 distvic famine situation in 22 districts had reache point. Many people were trapped in ina areas. The lives of some 20,000 familie than a milion cattle were severely affoc'e Fig. 244 A drought affected area in Balochistan where most ofthe livestock ded because of no alta forthe past three years Widespread famine leading to starvation ‘Malnutrition, health problems, starvation Migration from drou affected areas ight Breal Crop failure ath of] as have had no rain for three to eigh, © Most are ars. . No significant amount of rain is expected. ‘Women have io ravellong distances to getwaterind:n, Fla 247 temen rogione of ots. _! re she arene, wore sre Fa 245 Tec afectaa by Sroigh ns Pousan ey 200. seutbaurrn cole a wesom Baccsan were thao res 8\ 22animalsdic in six weeks: | _ Drought endangers | | Fig. 246 J) rare species in KNP | Beata syneal eas eee peace ee ear [ety i Reaches tre cbr eae ae Seapies ena ec es Sem eteerrecorsn spre, Sete cgeee esermirs crass Drought Management a Drought management can be done in three ways 1) Water storage schemes Some of the areas most seriously affected by ‘Water can be stored in water storage schemes si? Grought are the Pakistani provinces of Balochistan ag the reservoirs of dams and traditional wal and Sindh. Pakistani officials have reported the tanks for irrigating crops and forest areas. This following facts about the drought: helps to limit the losses caused by seasonal droug"* © Over 3.3 million people have been affected, —_in the affected areas. The areas that only receiv? including thousands who are now refugees. Monsoon rainfall in heavy showers during July a% © Hundreds of people have already died of thirst. August can utilize that extra water throughout th and starvation. year by a perennial canal system. More su” © About 30 million livestock have been affecte: Projects are required to meet the water deman#* including over 2 million that have already died. of the growing population. A now do sitet. ga2) The use of new technology e.g 4) the use of sea water through a desalination process (the removal of salt) b) the conversion of waste water into clean water through filtration and chemical treatment, ¢) the use of the varieties of seeds for crop cultivation which are drought-resistant and consume less water. The lining of canals to avoid the wastage and uneconomical use of existing water resources. In Pakistan large amounts of canal water are wasted due to seepage from unlined canals causing waterlogging and salinity. These waterlogged areas, which have stagnant water and patches of salt on the surface, cannot be used for cultivation. Such problems should be addressed promptly by taking the preventive and curative measures discussed in Unit 3. 3) Planning and management of water resources Furthermore, the government should eisurc high priority is given to the allocation of the resources for the basic needs of the people the economy, i. for agricultural and industrial Tennneenennlll Drought Management nr ee ‘Reclaiming "Desalination of wastewater and Seawater “tung int clean water eraecredgae Conservation ‘of water to aod shortage Using drought resistant varieties of ‘crops Drought is a natural hazard and it may be enhanced by human activities. It cannot be fully prevented but its intensity and frequency oan be reduced by certain measures. Climate Zones of Pakistan (QUESTIONS which to live Unit 2 \A With reference to temperature and rainfall, identify and explain the differences in the Climatic 2. How does the climate vary from place to place in each of the climatic zones to which you have referred in Question 1? Explain the factors that affect Pakistan's climate. 3. a) Describe the characteristics of the winter climate of the Northern Mountains. 1 4 w) ‘IL Explain how the winter climate of the Northern Mountains makes ita diffcult area it ») % Describe the characteristics of the summer climate of the Thar Desert. "jie Explain how the summer climate of the Thar Desert affects the way that the area is used. (Comendge © Lev! Posten Sites 205002 1 cf) & a. & (Jone 2000)Climate 4, Thyee types of rain are © ) Each of these three ty to produce rain. b) For each of the three ) For each of the three types i. state the time o ° ii. explain why in Pakistan a small amount of 4) In the Indus Plain the summer rainfall is not always reliable. What problems are ‘caused for agriculture, i. ifthe rainfall arrives early, ii. ifthe rainfall arrives late, ii, if the amount of rainfall varies considerably from one year to another? e) How may the problems you have given in [4] be overcome? (canaage 0 Level Paistn Sues 2058021 ¢ Je 2002) Study the map Fig. 2-A. In which season does area A receive most of its rainfall? Explain why area A has most of its rainfall in the season you have named ini |. Explain why Peshawar receives a higher rainfall than Quetta. (Combisge 0 Level Poistan Suces 205802 Ob (8 (i. sxperienced in Pakistan: pes of rain is associated types, explain how rising of rain referred to Why do many rivers in Pakistan flood in July? State one advantage that may occur when riv How may a cotton textile factory in Karachi be affected by July floods in Punjab? How and why may the economy of the area be affected by flooding? State two measures which have been taken to minimize the harmful effects of floods. (Comancae © Level Palistn Suis 205902 a) Study the map, Fig. 2-B, which shows the main monsoon wind and the rainfall distribution from July to September, i Explain why the monsoon wind that is shown develops. li, Describe the rainfall distribution shown in Fig. 2-B and explain how itis caused by the monsoon winds. How may storms and heavy rainfall cause problems for people in Pakistan? (Comorage © Lev! Pasta Suis 20580201 6&8 June 2006) >) f the year when it usually occt ssion, Convection. 1so0n, Depres ves plain why rising air is needed with rising air. Ex air is produced in Pakistan. in (a): urs in Pakistan: usually experienced. “aa rain is — Nov 2000) /ers flood.8. Study Fig. 2-C, which shows the desert climate of Nok Kundi. “ES 20+ temperature (ey 0 10 MAY "JUN JUL AUG’ SEP OCT NOV’ DEC Months JAN FEB MAR APR ') With reference to Fig. 2-C, describe the yearly distribution of temperature and rainfall in a desert climate. ii) Explain how the climate of desert areas affects agricultural and industrial evelopment. (cammnige 0 Love Patan txts 208802 05 0) & i) une 2010) 9. What are the advantages and disadvantages of winter rainfall in Northern Pakistan? (Caméndge © Level Pakistan Stes 20590? OS ¢ (in) June 2011)