Aerosols as climate drivers
Mira Pöhlker
Core Questions
- What is the role of aerosols and clouds in the climate system?
- How do their properties change due to human and natural impact?
Abstract
In addition to long-lived climate drivers such as CO2, aerosol particles represent a significant short-lived climate driver that can affect the Earth's radiative budget (Figure 1). Aerosols can either directly scatter or absorb sunlight, or act as cloud nuclei, thereby influencing the Earth's radiative balance. They can arise from spray, technical, and biological sources (Figure 2), and also volcanic eruptions (Figure 3). To gain a deeper understanding of how human activities have influenced the Earth's climate and how future climate change may unfold in the context of reduced human emissions, it is essential to have a basic grasp of the aerosol climate effect. However, this understanding is complex. Aerosols can both warm and cool the Earth's climate due to they impact on the shortwave and longwave radiation budget (cf. Figure 1).
This presentation will provide a fundamental understanding of the effect of aerosols on the Earth's climate and present the latest results obtained using a wide range of methods employed in aerosol and climate research.
Figure 3. William Turner's painting “Fighting Temeraire” from 1838, shortly after the Tambora eruption in 1815.
Source: see page 10 in [3].
Literature
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- Janine Fröhlich-Nowoisky, Christopher J. Kampf, Bettina Weber, J. Alex Huffman, Christopher Pöhlker, Meinrat O. Andreae, Naama Lang-Yona, Susannah M. Burrows, Sachin S. Gunthe, Wolfgang Elbert, Hang Su, Peter Hoor, Eckhard Thines, Thorsten Hoffmann, Viviane R. Després, Ulrich Pöschl: Bioaerosols in the Earth system: Climate, health, and ecosystem interactions. Atmospheric Research 182 (2016) 346-376.
- S. Brönnimann, D. Krämer: Tambora and the “Year Without a Summer” of 1816. A Perspective on Earth and Human Systems Science. Geographica Bernensia G90 (2016).
Talk on 16 January 2025 — Ringvorlesung in Winter Term 2024/25