India, Nov. 26 -- Delhi, Karachi, Shanghai, Dhaka, Manila, Seoul, and other such densely built Asian megacities could face an additional 2-7 degrees Celsius (degC) spike in local temperatures on top of global warming, by the end of century, new analysis has warned.

Even with world limits warming to 1.5degC to 2degC, the urban heat island effect could push everyday temperatures in these cities several degrees beyond the global average, according to the United Nation's 2025 Asia-Pacific Disaster Report.

In South and Southwest Asia, India, Pakistan and Bangladesh may endure over 300 days annually with a heat index above 35degC, with many regions suffering more than 200 days where it exceeds 41degC, the report, launched by the UN Economic a...