The temperature dependence of ice-nucleating particle concentrations affects the radiative properties of tropical convective cloud systems
2021
Abstract. Convective cloud systems in the maritime tropics play a critical role in
global climate, but accurately representing aerosol interactions within
these clouds persists as a major challenge for weather and climate
modelling. We quantify the effect of ice-nucleating particles (INPs) on the
radiative properties of a complex tropical Atlantic deep convective cloud
field using a regional model with an advanced double-moment microphysics
scheme. Our results show that the domain-mean daylight outgoing radiation
varies by up to 18 W m −2 depending on the chosen INP parameterisation.
The key distinction between different INP parameterisations is the
temperature dependence of ice formation, which alters the vertical
distribution of cloud microphysical processes. The controlling effect of the
INP temperature dependence is substantial even in the presence of
Hallett–Mossop secondary ice production, and the effects of secondary ice
formation depend strongly on the chosen INP parameterisation. Our results
have implications for climate model simulations of tropical clouds and
radiation, which currently do not consider a link between INP particle type
and ice water content. The results also provide a challenge to the INP
measurement community, as we demonstrate that INP concentration
measurements are required over the full mixed-phase temperature regime,
which covers around 10 orders of magnitude.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
85
References
3
Citations
NaN
KQI