Science Source

Arctic sea ice, Eurasia snow, and extreme winter haze in China

States that the East China Plains (ECP) region experienced the worst haze pollution on record for January in 2013
Shows that the unprecedented haze event is due to the extremely poor ventilation conditions, which had not been seen in the preceding three decades
Statistical analysis suggests that the extremely poor ventilation conditions are linked to Arctic sea ice loss in the preceding autumn and extensive boreal snowfall in the earlier winter.
Identifies the regional circulation mode that leads to extremely poor ventilation over the ECP region
Climate model simulations indicate that boreal cryospheric forcing enhances the regional circulation mode of poor ventilation in the ECP region and provides conducive conditions for extreme haze such as that of 2013
Finds that extreme haze events in winter will likely occur at a higher frequency in China as a result of the changing boreal cryosphere, posing difficult challenges for winter haze mitigation but providing a strong incentive for greenhouse gas emission reduction