Impact of nucleation on global CCN

Abstract. Cloud condensation nuclei (CCN) are derived from particles emitted directly into the atmosphere (primary emissions) or from the growth of nanometer-sized particles nucleated in the atmosphere. It is important to separate these two sources because they respond in different ways to gas and particle emission control strategies and environmental changes. Here, we use a global aerosol microphysics model to quantify the contribution of primary and nucleated particles to global CCN. The model considers primary emissions of sea spray, sulfate and carbonaceous particles, and nucleation processes appropriate for the free troposphere and boundary layer. We estimate that 45% of global low-level cloud CCN at 0.2%…

• SR
  Sight Research UK

  Awards: ncas10009, appraise010006, NE/D01395X/1
• NE
  Natural Environment Research Council

  Awards: appraise010006, ncas10009, NE/D01395X/1, NE/D01395X/1