Islamabad - Federal Minister for Climate Change Senator Mushahidullah Khan has warned of more extreme heat wave incidents in future in different parts of the country, particularly urban areas.

Addressing a press conference during launch of the ‘Heat Wave report’, the minister said; “We need to prepare now to cope with negative impacts of heat wave incidents, which more likely to become more frequent and intense in future.”

A severe heat wave struck the country in June this year, which caused high number of causalities, especially in Karachi. Most of the country was under the grip of heat wave during 17 to 24 June. As on June 20, high temperature was recorded in the southern parts of the country. The temperature ranged from 49 degree Celsius in Larkana and Sibi to 45 degree Celsius in Karachi.

In southern Punjab, 40 degree Celsius was recorded in Multan, whereas several areas of the Balochistan province were also affected where temperature touched 49 degree Celsius in Sibi and Turbat. Late in June, the minister Mushahidullah Khan had formed a committee of experts to investigate the causes of the blistering heat wave in the country so that fallouts of heat waves in future could be mitigated.

The expert heat wave group comprised former Director General of Pakistan Meteorological Department Dr Qamar uz Zaman Chaudhry, DG Pakistan Meteorological Department Dr Ghulam Rasul, Member DRR, National Disaster Management Authority Ahmad Kamal, DG National Health Emergency Preparedness Munir Ahmad Mangrio, Senior Scientist of the Global Change Impact Studies Centre Shahbaz Mahmood and representatives from Provincial Disaster Management Authorities.

Mushahidullah Khan told that the summer afternoons in Karachi during the month of June 15-16 displayed a typical normal moisture quantity and transport into the area from the Arabian Sea. The atmospheric conditions went anomalous after a ridge (extension of high pressure area) was extended over Balochistan and adjoining parts of the country, including Karachi. The formation of this ridge led to a weakened incoming sea breeze transport process from the Arabian Sea and consequently reduced the humidity levels below normal over Karachi on the afternoon of June 17, 2015. “The ridge further accentuated on June 18 and penetrated more into south and eastward parts of the country,” he added.

The minister explained; “The analysis of the lower atmosphere (1500 – 3000m above sea level) reveals that due to a low pressure area over northeastern parts of India and a shallow low over southeastern parts of Pakistan, the wind direction over Karachi remained north-westerly, which brought dry and modified warm air to Karachi. Similarly at 500 hPa (5000 m above sea level), as a result of a low pressure area over north-eastern parts of India the direction of winds passing over Karachi were north-westerly which also contributed in bringing dry and modified warm air to Karachi.”

Leading author of the report, former DG of Pakistan Meteorological Department Dr Qamar-uz-Zaman Chaudhry said that the atmospheric conditions mentioned above were the main cause of severe heat wave . Other factors like, persistent and somewhat unplanned urbanisation, deforestation, lack of green areas, open spaces, lack of hygiene practices, awareness, green building and roads materials and transportation systems created heat island effect which added up to the extreme temperatures. “Frequent and prolonged power outages, water supply constraints further decreased the capacity of inhabitants to combat adverse impacts of heat wave which resulted into historically an unprecedented large number of casualties in Karachi,” he added.

Chaudhry said further that a cyclonic system started to develop over the Sea on June 18, which concentrated into a depression on June 22, moved northeastwards, entered through Saurashtra and Kutch (India) on June 24, weakened into a low pressure area. It further moved northeastwards and laid over West Rajasthan (India) on June 25 June. He elaborated “Prolonged presence of this low pressure system in the vicinity of Sindh-Makran coast further reduced the flow of sea-breeze. The system further strengthened and blocked all the moisture transport and ventilating winds towards Karachi.”

Giving further details, Director General of the Pakistan Meteorological Department Dr Ghulam Rasul said that due to the low pressure area over north-east Arabian Sea, surface wind of Karachi during morning to early afternoon remained north-easterly during the heat wave period which brought extensive hot and dry air from Rajasthan (India) through heated land of Sindh, whereas surface wind in the late afternoon (1200 UTC) remained mostly south-westerly which brought lot of moisture, ultimately increasing the amount of humidity.

The expert group, who hammered out the heat wave report, have emphasised that the recent worst heat wave spell in the country demands a comprehensive strategy to cope with disastrous heat waves. However, they have recommended that an effective early warning system for heat waves as discussed above may be established in the country on priority basis.