Fight climate change - in white! The research team at Purdue University in the US state of Indiana has developed a white colour that almost completely reflects the light of the sun. The researchers conducted outdoor measurements and found out that the colour can keep surfaces up to 10.5 °C cooler than the surroundings at night. It can also cool surfaces by a good 4 °C compared to the surroundings during midday hours. This also works in winter at an outside temperature of 6 °C, according to the results. The new white colour is the result of many years of research. In the 1970s, radiant cooling paints were analysed as an alternative to air conditioning. Ultra-white paints are usually made of calcium carbonate. For us, this means - bring on the nice cool colour that has always played an important role in nature. Albeit hidden.... .