Trifluoroiodomethane as a Precursor to High Global Warming Potential Climate Pollutants: Could the Transformation of Climatically Benign CFI into Potent Greenhouse Gases Significantly Increase Refrigerant-Related Greenhouse Gas Emissions?

The transition away from the production and consumption of high global warming potential (GWP) hydrofluorocarbons (HFCs) under the 2016 Kigali Amendment to the Montreal Protocol on Substances that Deplete the Ozone Layer (Montreal Protocol) has prompted air conditioning, refrigeration, and heat pump equipment manufacturers to seek alternative refrigerants with lower direct climate impacts. Additional factors affecting alternative refrigerant choice include safety (i.e.

Chlorine activation and enhanced ozone depletion induced by wildfire aerosol.

Remarkable perturbations in the stratospheric abundances of chlorine species and ozone were observed over Southern Hemisphere mid-latitudes following the 2020 Australian wildfires. These changes in atmospheric chemical composition suggest that wildfire aerosols affect stratospheric chlorine and ozone depletion chemistry. Here we propose that wildfire aerosol containing a mixture of oxidized organics and sulfate increases hydrochloric acid solubility and associated heterogeneous reaction rates, activating reactive chlorine species and enhancing ozone loss rates at relatively warm stratospheric temperatures.

Photodissociation of particulate nitrate as a source of daytime tropospheric Cl.

Chlorine atoms (Cl) are highly reactive and can strongly influence the abundances of climate and air quality-relevant trace gases. Despite extensive research on molecular chlorine (Cl), a Cl precursor, in the polar atmosphere, its sources in other regions are still poorly understood. Here we report the daytime Cl concentrations of up to 1 ppbv observed in a coastal area of Hong Kong, revealing a large daytime source of Cl (2.