Karachi and the heat trapped in it – Prism

According to Mohammad Ameen, the control incharge of the Edhi Foundation in Karachi, their mortuaries saw an over three-fold increase in the number of bodies this summer. He added, however, that his organisation could not declare whether these victims had died from heatstroke.

“This is the government’s job,” he told Dawn.com. “But there was a time during these three months when the number of bodies arriving at our morgues was in the hundreds.”

Ganga Kumari, a 45-year-old lean woman, sits on a charpoy in the close-knit streets of Ranchor Line, one of the oldest and most dense settlements in Karachi. Beads of precipitation run down her face as she fans her husband, who is recovering from heart surgery, with an old newspaper.

Her street, once wide, has now been engulfed by encroachments, leaving only space for motorcycles and residents to pass by. Over the years, five-storey buildings have been erected on 120 square yards of land, each featuring at least eight apartments. The stuffed and dingy flats don’t allow air to pass. Venturing further into the neighbourhood, the houses get even more crammed until you can hardly see the sky above.

With Ganga sit a bunch of other women and men, all of them talking about the day’s activities. But soon the chatter subsides into silence as the heat begins to take its toll.

“This is an everyday routine … what can you do when it is so hot and there is no electricity,” she lamented. “These streets and the rooftops have become our abode, inside the house, it feels as if someone has locked us up in a hot room … it is difficult to even breathe.”

“My husband has it worse … the heat suffocates him and increases his blood pressure,” said Ganga, who works at a nearby school as a sweeper. “There is not even an open space or park nearby where we can go.”

Basically, concrete is making Karachi sweat, that too profusely.

Dr Noman Ahmed, head of the Department of Architecture and Planning at NED University, explained that commercial areas have air-conditioners that keep the indoor environment cool but their outer units work as exhausts that remit heat into the atmosphere.

City corridors that have tall buildings — the likes of Sharea Faisal, Tariq Road and Shahra-i-Quaideen — therefore, feel the heat island effect intensely. “These buildings block the wind corridor, so the heat instead of moving forward and dissipating, gets trapped in these locations and its impact is felt for a longer period of time,” Dr Ahmed explained.

It may not seem too important, but the colour of the material used for the infrastructure also plays a vital role here as it absorbs heat during the day and later radiates it out after sundown.

Moreover, UHI is also generated on streets and roads with high vehicular flow and traffic congestion where the heat generated by car engines gets stuck, increasing the felt temperature for people in the neighbourhood. The ground surface, usually asphalt, further enhances the heat retention.

And then there are informal settlements, home to a significant percentage of Karachi’s population, that contribute to the UHI effect by limiting air circulation and allowing heat to build up.

“Old katchi abadis located closer to the central areas of the city, such as Lower and Upper Gizri, Punjab Colony, Delhi Colony, Neelum Colony, and Lyari among others, initially had the normal pattern of development — ground or ground plus one structure. But they have now been replaced by six-storey buildings, standing very close to each other, that prevent air and sunlight from passing.

“This creates a very unhealthy environment in these areas; especially when the wind is scarce, it creates suffocation,” said Dr Noman, recounting that during the 2015 heatwave, hundreds of people hospitalised were those belonging to these informal settlements.

Muhammad Toheed, an urban planner and geographer, concurred, adding that this was further exacerbated by frequent power outages lasting 10 to 14 hours in many informal settlements.

“Without access to electricity, residents suffer from extreme heat, leading to health issues such as heatstroke, dehydration, and other heat-related illnesses. The absence of greenery and shade only worsens the situation, making living conditions in these areas unbearable,” he added.

Naveed Khan, a mechanic based in Lyari, may not be able to spell it out accurately but he knows all too well the curse of urban heat islands. One day in June 2015, he rushed home after begging his employer for a half-day. His seven-year-old son, who was playing in the streets with friends, had fainted. It was a heatstroke. Although generally believed to be easily curable, the episode damaged his kidney, leaving him writhing in pain for several days.

Even when he came back home from the hospital, Naveed and his wife would spend days by the bedside, taking turns to fan the little boy. Naveed lost his job that year too, and had to look for odd jobs to make a living.

According to Sarfraz, the temperature in Pakistan is becoming 0.18 degrees warmer per decade. But Karachi has it even worse, with its mercury increasing twice that of the country every 10 years. The chief meteorologist puts the blame on rapid urbanisation and deforestation.

Shahroz Siraj, popularly known as the ‘Tree Man of Pakistan’, is among those few people in Karachi who have taken on the responsibility to make the city breathable again. An engineer by profession, he embarked on the ‘green’ journey after the 2015 heatwave, when, Siraj recalled, mortuaries and hospitals were full to the brim.

“The first tree I planted was in North Karachi’s Sector 9,” he told Dawn.com. “One would assume that it would have been an easy job, but the reality is far from it. I remember I had knocked on a door in our neighbourhood and requested that the family water the newly planted sapling nearby. They downright refused, saying that they hardly had water for other chores.”

The next door Siraj went to too had a similar response. “That is when I realised that greening the city was directly proportional to awareness.”

Hence began the Tree Man’s drive. In the last nine years, he has visited madrassahs, schools, colleges, mosques, imambargahs and churches to educate fellow citizens about the importance of trees. During this time, he planted 150 tree saplings and set up four urban forests in his area.

“It is the responsibility of every person to plant at least four trees,” he stressed. “Trees are our sole solution as they turn carbon into oxygen. You can’t stop the temperature from rising, but you can at least create cool shades to rest under.”

Climate experts also told Dawn.com that the solution to Karachi’s woes lay in the transition to cleaner energy among other measures. The industrial sector, for one, can shift to renewable energy sources which would not just reduce emissions but also decrease the overall heat produced.

“Clean energy solutions often involve more efficient technologies that produce less heat and use less energy overall. This transition can help lower overall city temperatures and reduce the strain on the power grid (on-grid and off-grid options) leading to fewer outages and more reliable access to cooling during heatwaves or extreme temperatures,” remarked Toheed.

By reducing reliance on fossil fuels, the amount of waste heat generated in the city can be lowered. Solar panels, for example, can provide energy without producing additional heat, unlike traditional power plants.

However, Dr Noman highlighted that the current usage of solar in the city was rather haphazard. “People are using it in their homes and offices but that isn’t bringing about a larger positive impact … instead, we should integrate it into bulk energy production and the main grid,” he said, adding that there was a need to strategise solar usage.

When it comes to transportation, Karachi can promote the use of electric vehicles and improve public transportation to reduce heat and emissions. Nazifa highlighted that Euro5 fuel, which minimises the negative impact on the environment owing to a reduction in Sulphur and Benzene content by 98pc and 80pc respectively, was available but not completely adopted.

“Ideally the government should plan to switch to Euro6 because vehicular emissions contribute greatly to heat-trapping gases,” she said.

In the construction sector, adopting green building practices such as using reflective materials and incorporating natural ventilation can reduce the heat generated by buildings.

“Designers and architects should concentrate on green building designs and create zero-emission or energy-efficient buildings using lead certification — which is declaring buildings as low emission,” Nazifa stated, adding that shifting industries away from densely populated urban areas can also mitigate the effect of heat island effect.

Dr Noman, meanwhile, suggested cheaper solutions such as choice of paints — using white could help as it reflects the sun rays — and adding a layer of “choona” in the buildings. There are also other common techniques for vertical landscaping, whereby plantation can be introduced in highly congested areas.

The government also needs to seriously work on the regulation of informal settlements because unplanned densification of these areas is dangerous. For this, the NED dean has a solution.

“If there is more pressure on an area, a scientific exercise called urban regeneration can be adopted, through which small plots can be amalgamated into a big plot and there you make tall structures via proper planning which include open spaces and amenities. Here, people can be then accommodated via a proportionate formula,” Dr Noman suggested.