Rise in average temperature: Longer summers, warmer nights and extreme weather events
Research scientist says people in rural areas adjust well to climate changes than those in the cities
PHOTO: FILE
KARACHI:
The earth’s average temperature today is around one degree hotter than pre-industrial levels and while the change appears marginal, the effect it has is catastrophic. Global efforts are focused on not letting the temperature breach the 2°C threshold - a relatively safe level beyond which climate change effects such as droughts, floods and heatwaves are likely to become more severe and irreversible.
Qamaruz Zaman Chaudhry, a meteorologist and research scientist, says the temperature has increased with unique variation in different parts of the world, including Karachi. “The first six months of 2016 have been the hottest; they have surpassed the record of 2015, which was the hottest year,” he shares, mentioning the recent temperature in Kuwait, which shot up to 54°C. “This is from our region; luckily we did not have such an extreme event but we cannot rule out the possibility,” he warns.
Bilal Khalid, an environmental expert associated with Leadership for Environment and Development (Lead), says earlier this year the global average temperature rise crossed the threshold of one degree Celsius, which underlines the scale of the challenge.
Biodiversity in danger: Rapid global warming threatens ecosystems
Quoting a research published by University of Sargodha, which analysed temperature records for Karachi over the period of 1947-2005, Khalid says the study establishes that the mean annual temperatures for Karachi have risen by 2.25°C during this period. “Although the exact figure might be contested, there is strong evidence and consensus that mean annual temperatures in Pakistan, including Karachi, are rising,” he stresses.
Causes for warming
Urban planner Farhan Anwar says emissions from stationary and mobile sources like industries and transport, emissions from appliances used in homes and commercial buildings are some factors contributing to rising heat levels in Karachi. “Mass densification and vertical growth in the absence of proper environmental and planning safeguards could also be contributing to the possible urban heat island effect in the city,” he explains.
Erratic weather events more likely
While the rise in mercury can be directly attributed to climate change, Lead’s Khalid says there are numerous other anthropological factors that are increasing the intensity of high temperatures, especially in megacities such as Karachi. “These include lack of green spaces, exponential rise in concrete surfaces and poor ventilation in houses and buildings,” he lists.
Effects of warming
Meteorologist Chaudhry says the rise in average temperature has extended the period of summers, made the nights warmer and resulted in extreme events like heatwaves. “In Karachi, the situation is exacerbated because of humidity and urban factors,” he explains. “The cooling that is supposed to take place at night doesn’t happen as concrete buildings release heat they had absorbed during the day. The relief that used to come with the night is gone.”
Listing the impacts, Chaudhry says the increase in heat levels has severe implications on public health. “Heat puts stress on the human body and can cause dizziness, headache and fainting,” he says. “In extreme cases, it can be life threatening.” Rise in temperature, Chaudhry adds, increases energy consumption, putting pressure on the energy infrastructure. “Power generation systems in Pakistan cannot sustain the increase in demand and often break down during events of extreme heat,” he points out.
Khalid says the rise in temperatures has also increased the vulnerability of urban centres such as Karachi. “The rise in summer temperature poses a severe risk to the wellbeing of urban dwellers and also to the economic activity of the city,” says the Lead member. “Rising instances of heatwaves in South Asia are becoming a common occurrence, which can paralyse cities for days in addition to large scale fatalities. Unsustainable population levels, marginalised communities and ill-planned urban settlements are some of the key factors that exacerbate the impact of climate-induced calamities such as heatwaves. Moreover, in recent years, such calamities have led to widespread social unrest since they directly contribute to the rising inequality in developing countries.”
Mitigation
Chaudhry says because warming is a global phenomenon, efforts to curb it have to be global. What people of Karachi can do, he suggests, is to adapt to this change by adjusting their habits. “On the local level, we can make sure there’s a proper warning system, timely advice to modify or restrict activities and cooling centres to provide relief to those hit by heat,” he recommends.
The research scientist says people in rural areas adjust well to climate changes than those in the cities. “Labourers in our urban centres work the same number of hours even during heat events while farmers during hot days usually start work just around sun rise and return home before the sun reaches its peak,” he states.
Global warming altering sea as we know it
As the nature of heatwave events makes them hard to detect, Khalid says this causes large-scale casualties before the state can react. “The traditional disaster response model based on reactive and knee-jerk responses is incompatible for managing heatwaves. There is a need to develop a proactive heatwave management plan that includes an early warning system and clear response protocols,” he suggests.
Such a plan, Khalid says, will also require close coordination between various institutions since no government department can singlehandedly tackle the challenge. “Lastly, there is need for capacity-building and awareness-raising of all stakeholders to sensitise them about the risks and mitigation strategies for responding to heatwaves,” he stresses.
To mitigate the effect in the long term, urban planner Anwar says there’s a need for greater vegetation cover, vertical growth to correspond to the required environmental and planning provisions, transition to renewable sources of energy and promotion of public transport.
This is the first of a four-part series on the effects of climate change in Karachi
Published in The Express Tribune, September 16th, 2016.
The earth’s average temperature today is around one degree hotter than pre-industrial levels and while the change appears marginal, the effect it has is catastrophic. Global efforts are focused on not letting the temperature breach the 2°C threshold - a relatively safe level beyond which climate change effects such as droughts, floods and heatwaves are likely to become more severe and irreversible.
Qamaruz Zaman Chaudhry, a meteorologist and research scientist, says the temperature has increased with unique variation in different parts of the world, including Karachi. “The first six months of 2016 have been the hottest; they have surpassed the record of 2015, which was the hottest year,” he shares, mentioning the recent temperature in Kuwait, which shot up to 54°C. “This is from our region; luckily we did not have such an extreme event but we cannot rule out the possibility,” he warns.
Bilal Khalid, an environmental expert associated with Leadership for Environment and Development (Lead), says earlier this year the global average temperature rise crossed the threshold of one degree Celsius, which underlines the scale of the challenge.
Biodiversity in danger: Rapid global warming threatens ecosystems
Quoting a research published by University of Sargodha, which analysed temperature records for Karachi over the period of 1947-2005, Khalid says the study establishes that the mean annual temperatures for Karachi have risen by 2.25°C during this period. “Although the exact figure might be contested, there is strong evidence and consensus that mean annual temperatures in Pakistan, including Karachi, are rising,” he stresses.
Causes for warming
Urban planner Farhan Anwar says emissions from stationary and mobile sources like industries and transport, emissions from appliances used in homes and commercial buildings are some factors contributing to rising heat levels in Karachi. “Mass densification and vertical growth in the absence of proper environmental and planning safeguards could also be contributing to the possible urban heat island effect in the city,” he explains.
Erratic weather events more likely
While the rise in mercury can be directly attributed to climate change, Lead’s Khalid says there are numerous other anthropological factors that are increasing the intensity of high temperatures, especially in megacities such as Karachi. “These include lack of green spaces, exponential rise in concrete surfaces and poor ventilation in houses and buildings,” he lists.
Effects of warming
Meteorologist Chaudhry says the rise in average temperature has extended the period of summers, made the nights warmer and resulted in extreme events like heatwaves. “In Karachi, the situation is exacerbated because of humidity and urban factors,” he explains. “The cooling that is supposed to take place at night doesn’t happen as concrete buildings release heat they had absorbed during the day. The relief that used to come with the night is gone.”
Listing the impacts, Chaudhry says the increase in heat levels has severe implications on public health. “Heat puts stress on the human body and can cause dizziness, headache and fainting,” he says. “In extreme cases, it can be life threatening.” Rise in temperature, Chaudhry adds, increases energy consumption, putting pressure on the energy infrastructure. “Power generation systems in Pakistan cannot sustain the increase in demand and often break down during events of extreme heat,” he points out.
Khalid says the rise in temperatures has also increased the vulnerability of urban centres such as Karachi. “The rise in summer temperature poses a severe risk to the wellbeing of urban dwellers and also to the economic activity of the city,” says the Lead member. “Rising instances of heatwaves in South Asia are becoming a common occurrence, which can paralyse cities for days in addition to large scale fatalities. Unsustainable population levels, marginalised communities and ill-planned urban settlements are some of the key factors that exacerbate the impact of climate-induced calamities such as heatwaves. Moreover, in recent years, such calamities have led to widespread social unrest since they directly contribute to the rising inequality in developing countries.”
Mitigation
Chaudhry says because warming is a global phenomenon, efforts to curb it have to be global. What people of Karachi can do, he suggests, is to adapt to this change by adjusting their habits. “On the local level, we can make sure there’s a proper warning system, timely advice to modify or restrict activities and cooling centres to provide relief to those hit by heat,” he recommends.
The research scientist says people in rural areas adjust well to climate changes than those in the cities. “Labourers in our urban centres work the same number of hours even during heat events while farmers during hot days usually start work just around sun rise and return home before the sun reaches its peak,” he states.
Global warming altering sea as we know it
As the nature of heatwave events makes them hard to detect, Khalid says this causes large-scale casualties before the state can react. “The traditional disaster response model based on reactive and knee-jerk responses is incompatible for managing heatwaves. There is a need to develop a proactive heatwave management plan that includes an early warning system and clear response protocols,” he suggests.
Such a plan, Khalid says, will also require close coordination between various institutions since no government department can singlehandedly tackle the challenge. “Lastly, there is need for capacity-building and awareness-raising of all stakeholders to sensitise them about the risks and mitigation strategies for responding to heatwaves,” he stresses.
To mitigate the effect in the long term, urban planner Anwar says there’s a need for greater vegetation cover, vertical growth to correspond to the required environmental and planning provisions, transition to renewable sources of energy and promotion of public transport.
This is the first of a four-part series on the effects of climate change in Karachi
Published in The Express Tribune, September 16th, 2016.