The forests of central Europe have undergone remarkable transitions in the past 40 years as air quality has improved dramatically. Retrospective analysis of Norway spruce (Picea abies) tree rings in the Czech Republic shows that air pollution (e.g. SO2 concentrations, high acidic deposition to the forest canopy) plays a dominant role in driving forest health. Extensive soil acidification occurred ...

Elevated ground-level ozone, a result of human activity, is known to reduce plant productivity, but its influence on tropical forests remains unclear. Here authors estimate how increased ozone exposure has affected tropical-forest productivity and the global carbon cycle. Authors experimentally measure the ozone susceptibility of various tropical tree species, and then incorporate these data into ...

Background tropospheric ozone (O3) is increasing particularly over China and India, and becomes a major threat to Asian forests. By using the coupled WRF-Chem model at high spatial resolution (8 km) over Asia in 2015, authors showed that both standards AOT40 (European) and W126 (United States) underestimated the O3 risk to deciduous forests and overestimated it to evergreen forests compared to the...

The Global Methane Assessment shows that human-caused methane emissions can be reduced by up to 45 per cent this decade. Such reductions would avoid nearly 0.3°C of global warming by 2045 and would be consistent with keeping the Paris Climate Agreement’s goal to limit global temperature rise to 1.5 degrees Celsius (1.5˚C) within reach.The assessment, for the first time, integrates the climate and ...

The atmospheric methane burden is increasing rapidly, contrary to pathways compatible with the goals of the 2015 United Nations Framework Convention on Climate Change Paris Agreement. Urgent action is required to bring methane back to a pathway more in line with the Paris goals. Emission reduction from “tractable” (easier to mitigate) anthropogenic sources such as the fossil fuel industries and la...

Methane is the 2nd most important anthropogenic greenhouse gas after carbon dioxide. Since the pre-industrial era, methane concentrations have more than doubled, and at present sources related to human activities are about 50% larger than natural ones. After a period of stagnation, methane concentrations are increasing again since the last decade, and by 2020, may reach levels that match the most ...

Background and aimsConcentrations of particulate matter (PM) regularly exceed levels recommended in the 2021 revision of the World Health Organization (WHO) air quality guidelines (AQGs) in many urban and rural areas of the world, and over 8 million people die prematurely every year from exposure to PM. In addition to affecting people living in rural areas, PM also has an impact on the growth, pro...

The purpose of this publication is to document the current knowledge of the damaging effects of tropospheric (ground-level) ozone pollution on food crops around the world and to discuss ways of mitigating these effects. The document makes the case for the inclusion of ozone in future crop yield predictions and recommends that management practices being developed to cope with climate change should ...

Modelled average percentage yield loss due to ground-level ozone pollution (per 1 degree by 1 degree grid cell) are presented for the crops maize (Zea mays), rice (Oryza sativa), soybean (Glycine max) and wheat (Triticum aestivum) for the period 2010-2012. Data are on a global scale, based on the distribution of production for each crop, according to the Food and Agriculture Organisation’s (FAO) G...

Under climate warming, the trade-off between maintaining forest carbon sinks and meeting growing food demands presents a great challenge for land systems. Ground-level ozone, an oxidative air pollutant, exacerbates this issue by entering plant stomata and causing phytotoxic damage to crops. Previous studies have largely overlooked the physiological response of plant stomata (e.g., stomatal apertur...