Climate change : how guilty are aerosol particles ?

Shedding light on grey areas

"The effects of aerosols on the climate are still largely unknown because their treatment in current models is insufficient", Dr. Paolo Tuccella points out. "We need to further investigate their impact on environmental change and that means including aerosols which have been ignored or insufficiently studied in the past and their impact on various environmental components"."Unlike black carbon, which has been known for some time to absorb sunlight and warm the atmosphere, brown carbon, its organic cousin, is just beginning to be taken into account as a possible contributor to climate change ", the researcher in atmospheric physics explains. "Including this species in current models is crucial if we want to obtain more realistic estimates". In addition to investigating the role of brown carbon on environmental change, Dr. Paolo Tuccella also intends to shed light on two other major grey areas of aerosol research. Specifically, the project aims to study the effect of ageing on the ability of aerosols to scatter and absorb light, as well as the impact of aerosol particles deposition on the capacity of ice to reflect light. "The latter phenomenon likely contributes to an enhancement of the melting of Arctic sea ice, Arctic and Alpine glaciers and snow pack", the researcher specifies. Taking these three innovative aspects into account, Dr. Paolo Tuccella aims to obtain better estimates of the budget of BC, BrC and soil dust and to refine our understanding of the direct and indirect radiative effect of these particles at global and European scales with a focus on the Mediterranean basin.

The Earth's radiation field relies on a fragile balance. Over the course of history, naturally-processed aerosols have proven their ability to punctually offset this balance and affect the Earth's climate. A recent example is the eruption of Mount Pinatubo in 1991, whose production of sulphate aerosols pushed down global average temperatures for as long as two to three years. But the emission of particles resulting from human activity is now threatening to durably throw the Earth's climate off balance, with far-reaching, long-lasting and, in many cases, devastating effects. To avoid an irreversible build-up of nocive and climate forcing particles, we need to act urgently and efficiently. In this sense, initiatives such as Dr. Paolo Tuccella's project are absolutely crucial to the implementation of informed and effective mitigation policies.