STRATOSPHERE Pyrocumulonimbus affect average stratospheric aerosol composition


Pyrocumulonimbus (pyroCb) are wildfire-generated convective clouds that can inject smoke directlyinto the stratosphere. PyroCb have been tracked for years, yet their apparent rarity and episodic naturelead to highly uncertain climate impacts. In situ measurements of pyroCb smoke reveal its distinctiveand exceptionally stable aerosol properties and define the long-term influence of pyroCb activity onthe stratospheric aerosol budget. Analysis of 13 years of airborne observations shows that pyroCb areresponsible for 10 to 25% of the black carbon and organic aerosols in the“present-day”lowerstratosphere, with similar impacts in both the North and South Hemispheres. These results suggest that,should pyroCb increase in frequency and/or magnitude in future climates, they could generate dominanttrends in stratospheric aerosol.

Research Program: 
Tropospheric Composition Program (TCP)