Ryan Hossaini

TL;DR: The increase in the methane burden began in 2007, with the mean global mole fraction in remote surface background air rising from about 1775 ppb in 2006 to 1850 ppb by 2017, at rates not observed since the 1980s as discussed by the authors.

TL;DR: The nature and timescales of ozone recovery are discussed, the extent to which it can be currently detected in different atmospheric regions is explored, and climate change is masking ozone recovery from ozone-depleting substances in some regions and will increasingly affect the extent of recovery.

TL;DR: Short-lived halogens are produced naturally and anthropogenically, and are not governed by the Montreal Protocol like halocarbons, and they destroy lowerstratospheric ozone, resulting in a net cooling effect since pre-industrial times as mentioned in this paper.

TL;DR: Use of atmospheric model simulations shows that although currently modest, the impact of dichloromethane on ozone has increased markedly in recent years and if these increases continue into the future, the return of Antarctic ozone to pre-1980 levels could be substantially delayed.

TL;DR: Ground-based and satellite data are presented that show a recent and significant increase in hydrogen chloride (HCl), the main stratospheric chlorine reservoir, starting around 2007 in the lower stratosphere of the Northern Hemisphere, in contrast with the ongoing monotonic decrease of near-surface source gases.