A New Proxy for Cloud Condensation Nuclei from Polarization Measurements and its Use for Quantifying Aerosol-Cloud Interactions
Abstract
Aerosols serve as cloud condensation nuclei (CCN) and thereby affect the cloud droplet number concentration (Nd) and consequently cloud albedo. This effect, known as the radiative forcing due to aerosol-cloud interactions (RFaci) is one of the largest contributors to the uncertainty in estimates of anthropogenic forcing of climate change. Satellite studies of aerosol-cloud interactions are almost solely based on relationships between aerosol optical properties and Nd. This leads to considerable uncertainties because optical properties are not directly related to CCN capability. In this study, we use recent satellite retrievals of aerosol size distribution, shape, and column number from the POLDER-3 instrument to provide a better CCN proxy, Nccn. From relationships between Nccn retrieved from POLDER and Nd retrieved from MODIS, we find that that the CCN capability of aerosols depends strongly on aerosol size and shape. Using the POLDER-3 derived Nccn we find much stronger aerosol-cloud interactions than previous observation based studies using optical properties.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.A53G..07H
- Keywords:
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- 0305 Aerosols and particles;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0305 Aerosols and particles;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0305 Aerosols and particles;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0305 Aerosols and particles;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0320 Cloud physics and chemistry;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0320 Cloud physics and chemistry;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0321 Cloud/radiation interaction;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0321 Cloud/radiation interaction;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 3305 Climate change and variability;
- ATMOSPHERIC PROCESSES;
- 3305 Climate change and variability;
- ATMOSPHERIC PROCESSES;
- 3311 Clouds and aerosols;
- ATMOSPHERIC PROCESSES;
- 3311 Clouds and aerosols;
- ATMOSPHERIC PROCESSES;
- 3311 Clouds and aerosols;
- ATMOSPHERIC PROCESSES;
- 3311 Clouds and aerosols;
- ATMOSPHERIC PROCESSES;
- 3354 Precipitation;
- ATMOSPHERIC PROCESSES;
- 3354 Precipitation;
- ATMOSPHERIC PROCESSES