Volcanic aerosol effects on cirrus clouds and climate

Project: Research


Volcanic eruptions that reach the stratosphere affect climate by increasing the stratospheric aerosol load, blocking some of the solar radiation from reaching Earth’s surface. This is an important natural climate driver and large explosive volcanic eruptions are estimated to have lowered the global mean temperature by more than 0.5 °C. How cirrus clouds are affected by the volcanic particles as they descend from the stratosphere, is very uncertain. This project aims at estimating the radiative impact of volcanic aerosols through their interactions with cirrus clouds. It is important to understand this natural climate driver in order to increase our fundamental understanding of the climate system, to better gauge human influence on climate. This research is furthermore essential, considering the ongoing discussions of deliberate manipulation of Earth’s climate by the emissions of sulfate aerosol into the stratosphere, mimicking volcanic eruptions.
In this project we will use satellite observations of cirrus clouds properties to create a climatology from 2006 to present. We will combine this climatology with a unique satellite dataset of aerosol optical depth (AOD) of the lowermost stratosphere, to investigate the relationships between cirrus cloud properties and variations in AOD induced by explosive volcanoes. Furthermore, simulations with an Earth System Model will be run to assess whether the model can reproduce the results from the satellite study.
Effective start/end date2018/10/012020/09/30