Contrasting effects of convective intensity and organisation on anvil cloud radiative effect observed using cloud tracking

Tropical anvil clouds have significant impacts on the atmosphere due to their cloud radiative effect (CRE), and their response to warming remains one of the largest uncertainties in future climate projections. Recent research has highlighted both the importance of changes in anvil cloud structure and changes in convective mass flux in a warmer climate to CRE feedbacks. However, understanding of these processes is limited due to a lack of observations linking convective processes to anvil cloud properties across their entire lifetimes. We apply the tobac-flow algorithm to a year of Meteosat SEVIRI observations over Africa and the tropical Atlantic to detect and track convective cores and their subsequent anvil clouds to investigate the impact of convective dynamics on anvil clouds. By combining this cloud tracking dataset with retrieved cloud properties and broadband fluxes, changes in the intensity and organisation of convection can be linked to changes in anvil CRE. Overall, both more intense and more organised convection tends to result in anvils with positive CRE, as these storms produce higher, colder anvil clouds and, over land, anvils that exist for longer at night. However, when controlling for the anvil temperature and time of day, more intense convection tends to result in positive CRE, while more organised convection results in a negative CRE. We attribute these differences to changes in anvil structure, as we observe that more organised convection tends to produce thicker anvils, while more intense convection results in thinner anvils. The contrasting effects of different convective processes on anvil CRE highlight the importance of understanding the mechanisms through which convective dynamics affect anvil structure, and indicate that different changes in convective processes may lead to regional differences in anvil cloud feedbacks.