Models are critical to testing hypotheses and predicting outcomes. Models of climate change attempt to explain past events and predict future ones using data related to man-made and natural climate drivers. Aerosol particles result from both human activity and natural emissions. Significant uncertainty exists regarding their net effect on climate. One way to distinguish them is to look at pre-industrial environments when only natural aerosol emissions were present. The EU-funded CHAPAs project is studying aerosols in pristine environments like the Arctic and Siberia as a proxy. Environmental measurements and laboratory experiments will help scientists quantify the ways in which new aerosol particles form and grow, pointing to pre-industrial aerosol nucleation mechanisms that could enhance the accuracy of climate models. https://cordis.europa.eu/project/id/850614
In CHAPAs we organize intensive long-term measurements in pristine preindustrial-like environments. Using state-of-the-art chemical ionization mass spectrometry, we retrieve the chemical cluster composition and the vapours concentration. Additionally, we also perform short intensive measurements in the most challenging location or where is not possible to organize long term measurements. Below some example of our latest campaigns:
https://www.helsinki.fi/en/researchgroups/atmosphere-biosphere-cryosphere-inter…
https://www.helsinki.fi/en/news/mathematics-and-science/climbing-more-5200-metr…
https://www.helsinki.fi/en/news/mathematics-and-science/natural-himalayan-aeros…
This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 850614).
We are surrounded by plastic material and plastic debris have been found even in the most remote area of our planet. Plastic in the environment undergoes to a slow degradation procced that leads to formation of small fragments called micro and nanoplastics. These small plastic debris can also enter the environment through the use of products which contains micro and nanoplastics. Their behaviour in the environment can be significantly different compared to larger plastic debris due to the smaller size and the increase of the surface to volume ratio.
In our group we investigate the interactions between these small plastic debris and the surrounding environment, especially sunlight and oxidants both in the gas and in the liquid phase. In parallel, we are developing methods and procedures to collect and analyse nanoplastics and small microplastics in environmental samples with aim of mapping nanoplastic pollution. Through theoretical models we will try to simulate the environmental impact of nanoplastic pollution under different scenarios.
Photo-oxidation and oxidation become important chemical transformation pathway when the size of plastic debris decreases, because reactivity is proportional to the surface to volume ratio. We study the interactions between small plastic particles (from 100 nm up to few µm) and oxidants in gas and in liquid phase such as ozone and hydroxyl radicals. In our experiments we characterize the products released (in the atmosphere and in liquid phase) by the plastic degradation, the chemical and morphological changes in the plastic particles and we measure the kinetic of the transformation processes.
The analysis of small microplastics and nanoplastics is challenging due to instrumental limitations, however it is essential to assess the occurrence of nanoplastic in the environment and identify the most polluted areas. We are developing a procedure to sample and isolate nanoplastics and small microplastics and we are testing methods and instrument for the characterization and quantification of these plastics.
The data collected in the lab and the field are useful to develop and implement existing theoretical models to simulate the reactivity of nanoplastic in the environment and assess their potential impact on natural photochemical processes, sea-atmosphere exchanges and the carbon cycle.
This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 948666).