SCOTTISH researchers have warned that increasing use of air conditioning will add to global warming and bring further heat extremes the tropical areas in Asia, Africa and Latin America.

Glasgow Caledonian University’s Professor Rohinton Emmanuel highlights the importance of developing new means of "climate-sensitive" urban design to manage rising temperatures rather than exacerbating the problem with air cooling in the journal Urban Climate, .

With air conditioning systems providing less exposure to heat, our bodies can also fail to acclimatise physiologically to summer conditions.

They can also increase "heat-island’ phenomena, where the temperature of the central area of a city becomes high because of an increase in artificial heat exhausted from buildings.

Prof Emmanuel proposes a new way of making tropical cities cooler through design, including creating "canyon-like" shopping streets with rows of buildings providing adequate protection from rain and sun, gathering places located near urban waterfronts and new networks of pedestrian links independent of the city streets.

These would feature shaded pathways, strategically placed and adequate vegetation cover and water misting.

He added: “In our increasingly urbanised world, most people will experience the effects of climate change in cities.

"This is particularly so in the tropical world, where the effect of local warming super-imposed on the regional and global warming, will make urban life intolerable.

"It is therefore essential that cities are planned in a climate-sensitive manner to act as the first line of defence against the negative consequences of a warming world.”

Researchers estimate that, in Sub-Saharan Africa, unprecedented heat extremes will cover an increasing percentage of land area as global warming intensifies from 2 to 4 °C, resulting in significant changes in vegetative cover and drought events.

In Southeast Asia, heat extremes are expected to cover nearly 60–70 per cent of land area in summer, even under a 2°C global warming scenario.