Cloth that keeps cool

 New fabric found to make urban ‘heat islands’ more bearable 

world’s cities and global warming

1 global temperatures and urban populations rise.

2 the world’s cities have become “urban heat islands,” with tight-packed conditions and thermal radiation emitting from pavement and skyscrapers / big building trapping and magnifying these temperatures.

 3 With 68% of all people predicted to live in cities by 2050, this is a growing, deadly problem.

new wearable fabric 

that can help urban residents survive the worst impacts of massive heat caused by global climate change,

 Also use in in clothing, building and car design, and food storage.

Test results

अन्य पदार्थों से तुलना 

१ broadband emitter fabric

In tests under the Arizona sun, the material kept 2.3 degrees Celsius cooler than the broadband emitter fabric used for outdoor endurance sports 

२ commercialised silk commonly

8.9 degrees Celsius cooler than the commercialised silk commonly used for shirts, dresses and other summer clothing. 

और क्या फ़ायदा हो सकता है ?

This, the team hopes, will help many avoid the heat-related hospitalisations and deaths seen in global population centres this year alone.

क्या होती है प्रोसेस 

1 cooling fabric for outdoor sports works by reflecting the sun’s light in a diffuse pattern so it does not blind onlookers . 

2 But in an urban area  the sun is only one source of heat. While the sun bakes from above, thermal radiation emitted from buildings and pavement blast city-dwellers with blistering heat from the sides and below. 

3 About 97% of the clothes are being heated by the thermal radiation coming at them from the sides and below, which broadband emitter fabric does not fight.

 This means many materials that perform well in lab tests will not help city-dwellers in Arizona,Southeast Asia and China when massive heat waves hit them.

The University of Chicago team’s new textile

which has received a provisional patent, can help provide a passive cooling system that can supplement and reduce the need for energy- and cost-intensive systems.

Another use of clothing

A thicker version of the fabric protected by an invisible layer of polyethylene could be used on the sides of buildings or cars, lowering internal temperatures and reducing the cost and carbon impact of air conditioning.

 Similarly, the material could be used to transport and store milk and other foods that would otherwise spoil in the heat, cutting refrigeration’s impact.

Source the hindu