DATE: April 20, 2018
SNIP: Aerosols, tiny particles that are suspended in the atmosphere, contribute significantly towards climate change.
The scientists’ observations also reveal an enormous difference between today’s polluted atmosphere and that of pre-industrial times. Aerosol concentrations in the pristine pre-industrial atmosphere resemble their Amazonian findings: high Upper Troposphere (UT) and low Lower Troposphere (LT) aerosol levels. However, in polluted continental regions, aerosol concentrations are generally much higher at ground level than in the UT. In an era where humans are the dominant influence on climate and the environment, the aerosol concentration profile has “been turned upside down,” say the journal paper authors. The consequences for Earth’s climate are significant. “By their radiative and microphysical effects on convection dynamics, aerosols are also able to increase upper tropospheric humidity, which plays an important role in the Earth’s radiation budget and may also affect the potential for aerosol nucleation in the UT, thus providing an additional feedback,” the authors conclude.