Beijing: That symbol of modern Beijing life - the pollution mask - has served a new purpose this winter.

As blue skies abound, and pollution plummets, the mask is being donned to simply warm faces on city streets.

Temple of Heaven with blue sky in Beijing. Blue sky days are now less rare. Credit:Shutterstock.com

A report by Greenpeace released on Thursday confirmed what Beijing residents have happily noticed - levels of the air pollutant PM 2.5 fell by 54 per cent in the last three months of 2017.

Greenpeace said a 'winter action plan' targeting Beijing, Tianjin and 26 northern cities had resulted in "dramatic falls in pollution in the area".