Nearly 800 people have died so far in a heat wave in southern Pakistan's financial capital of Karachi, prompting Pakistani Prime Minister Nawaz Sharif to declare a state of emergency. The heat wave has brought attention to the country's public service woes after Karachi, home to 20 million, was under-equipped to provide adequate health services to those seeking attention amid temperatures reaching up to 44 degrees Celsius (110 degrees Fahrenheit) with high humidity.

Studies show extreme weather events, including heat waves, can be expected to increase in frequency and intensity with climate change. An Intergovernmental Panel on Climate Change report released last year said heat waves are likely to occur more often and last longer.