Extreme heat impacting millions in Pakistan

A heat wave, or heatwave, is a period of excessively hot weather, which may be accompanied by high humidity, especially in oceanic climate countries. While definitions vary, a heat wave is usually measured relative to the usual weather in the area and relative to normal temperatures for the season. Temperatures that people from a hotter climate consider normal can be called a heat wave in a cooler area if they are outside the normal climate pattern for that area. The World Meteorological Organization, defines a heat wave as five or more consecutive days of prolonged heat in which the daily maximum temperature is higher than the average maximum temperature by 5 °C (9 °F) or more. However, some nations have come up with their own criteria to define a heat wave.

Causes of heatwave

Heat waves begin when high pressure in the atmosphere moves in and pushes warm air toward the ground. That air warms up further as it is compressed, and we begin to feel a lot hotter. The high-pressure system pressing down on the ground expands vertically, forcing other weather systems to change course.

According to National Weather Department a heatwave is defined as a period of unusually hot weather that typically lasts two or more weeks. To be considered a heatwave, the temperatures have to be outside the historical averages for a given area. A heatwave occurs when a system of high atmospheric pressure moves into an area and lasts two or more days. In such a high-pressure system, air from upper levels of our atmosphere is pulled toward the ground, where it becomes compressed and increases in temperature.

This high concentration of pressure makes it difficult for other weather systems to move into the area, which is why a heatwave can last for several days or weeks. The longer the system stays in an area, the hotter the area becomes. The high-pressure inhibits winds, making them faint-to-nonexistent. Because the high-pressure system also prevents clouds from entering the region, sunlight can become punishing, heating up the system even more. The combination of all of these factors come together to create the exceptionally hot temperatures we call a heatwave.

Heatwave In Pakistan

A severe heat wave with temperatures as high as 49 °C (120 °F) struck southern Pakistan in June 2015. It caused the deaths of about 2,000 people from dehydration and heat stroke, mostly in Sindh province and its capital city, Karachi. The heat wave also claimed the lives of zoo animals and countless agricultural livestock. The event followed a separate heat wave in neighboring India that killed 2,500 people in May 2015.

According to National Weather Forecasting Center, Islamabad. Severe Heat wave conditions predicted during the week.  Pakistan’s Balochistan region, has been suffering through weeks of temperatures that have repeatedly hit almost 50C (122F), unprecedented for this time of year. Locals have been driven into their homes, unable to work except during the cooler night hours, and are facing critical shortages of water and power.

 Pakistan have recorded their highest average temperatures on record

As the heatwave has exacerbated massive energy shortages across  Pakistan,  now barely receives any electricity, with up to nine hours of load shedding every day, meaning that air conditioners and refrigerators cannot function. “We are living in hell,” people say.

Sherry Rehman, Pakistan’s minister for climate, told the Guardian that the country was facing an “existential crisis” as climate emergencies were being felt from the north to south of the country. Rehman warned that the heatwave was causing the glaciers in the north of the country to melt at an unprecedented rate, and that thousands were at risk of being caught in flood bursts. She also said that the sizzling temperatures were not only impacting crops but water supply as well. “The water reservoirs dry up. Our big dams are at dead level right now, and sources of water are scarce,” she said.

The World Meteorological Organisation said in a statement that the temperatures in India and Pakistan were “consistent with what we expect in a changing climate. Heatwaves are more frequent and more intense and starting earlier than in the past.” A week ago,  Jacobabad, a city in Pakistan’s Sindh province, which a 2021 Amnesty International report categorized as “unlivable for humans,” reached 120.2 Fahrenheit, a record high for the Northern Hemisphere this year, according to data from the Pakistan meteorological department.

Heatwave Effects

The extreme heat is impacting hundreds of millions of people in one of the most densely populated parts of the world, threatening to damage whole ecosystems. Heatwaves can burden health and emergency services and also increase strain on water, energy and transportation resulting in power shortages or even blackouts. Food and livelihood security may also be strained if people lose their crops or livestock due to extreme heat.

• Heat-related illness occurs when the body severely overheats. It’s like having a fever but there’s no infection to cause it. This can occur when a child is exposed to high temperatures for a long period of time and the body’s ability to cope with the heat wears out. Symptoms of heat-related illness range from headaches and muscle cramps to vomiting, and, if severe enough, confusion or, if extremely severe, unconsciousness. Some children may be more at risk for heat-related illness because they have certain medical conditions or take certain medications.

• As the body gets hotter, blood vessels open up. This leads to lower blood pressure and makes the heart work harder to push the blood around the body. This can cause mild symptoms such as an itchy heat rash or swollen feet as blood vessels become leaky. At the same time, sweating leads to the loss of fluids and salt and, crucially, the balance between them in the body changes. This, combined with the lowered blood pressure, can lead to heat exhaustion. Symptoms include

  • dizziness
  • nausea
  • fainting
  • confusion
  • muscle cramps
  • headaches
  • heavy sweating
  • tiredness

  Heatwave impacts crop growth and development at different levels like soil moisture uptake, root and shoot growth, photosynthesis, respiration, plant water uptake and final yield. Heatwave competes for soil moisture by hastened evaporation, leaving almost no moisture for uptake by plants.

   

   

How to prevent from Heatwave

In summer, heat waves can strike areas of the country where cooler climates are the norm. In these areas, many homes do not have air conditioning, and surviving in the extreme temperatures becomes a challenge for everyone. The following steps can help you keep cool during a heat wave even if you have an air-conditioned home.

• Use box fans and ceiling fans to promote air circulation throughout your home. Opening doors in the house and using box fans to push hot air outdoors can function as an “exhaust” system and draw cooler evening air into the house. In the cooler evenings, open all windows and promote as much air circulation as possible. When the sun rises, close all doors and windows, making sure to close curtains and blinds as well, to keep the indoors cool for as long as possible. When the outside air cools to a lower temperature than inside (usually in the evenings or at night), open up the windows and turn on the fans again.
• Take advantage of the cooling power of water. Fill buckets or basins and soak your feet. Wet towels and bandannas can have a cooling effect when worn on the shoulders or head. Take cool showers or baths, and consider using a spray bottle filled with cold water for refreshing spritzes throughout the day.
• Head downstairs. Since hot air rises, the upper stories of a home will be warmer than the ground floor. A basement can be a cool refuge from the midday heat.
• Eliminate extra sources of heat. Incandescent light bulbs can generate unnecessary heat, as can computers or appliances left running. Eat fresh foods that do not require you to use the oven or stove to prepare.
• Remember to maintain an adequate level of hydration, which means you’ll need to consume more water than you usually do when it’s hot. If you’re sweating profusely, you will also need to replace electrolytes by eating a small amount of food with your water or by drinking specially-formulated electrolyte replacement drinks. Thirst is the first sign of dehydration; you should drink sufficient amounts of fluids before you feel thirsty in order to prevent dehydration.
• Avoid alcoholic beverages and caffeine, as both of these substances can act as diuretics and promote dehydration.
• For a homemade “air conditioning” system, sit in the path of a box fan that is aimed at an open cooler, or pan filled with ice.
• Try to visit public buildings with air conditioning during the hottest hours of the day if the heat becomes unbearable. Libraries, shopping malls, and movie theaters can all be good places to cool down.
• Don’t eat large, protein-rich meals that can increase metabolic heat and warm the body.
• Be able to recognize the symptoms of heat-related illnesses and true heat emergencies (heat cramps, heat rash, heat exhaustion, heat stroke). Call emergency services (911) in the event of a heat emergency and try to cool the victim until help arrives.
• Finally, remember that pets also suffer when the temperature rises. Cooling animals (dogs, rabbits, cats) by giving them a “cool” bath or shower will help keep their body temperature down. A cool towel on a tile floor to lay on, a cool towel or washcloth laying over the skin next to a fan will also help cool the animal. Make sure they have plenty of cool water to drink as well. Signs of a heat stroke in a pet are:
• rapid panting,
• wide eyes,
• lots of drooling,
• hot skin,
• twitching muscles,
• vomiting and
• a dazed look.