The article highlights a critical aspect of environmental degradation: the rising soil nitrous acid (HONO) emissions driven by climate change and fertilization, which accelerate global ozone pollution. A team of researchers from The Hong Kong Polytechnic University has examined global soil HONO emissions data from 1980 to 2016 and incorporated them into a chemistry-climate model. Their findings reveal that soil HONO emissions contribute significantly to the increase in the ozone mixing ratio in air, which has negative impacts on vegetation.

The researchers found that soil HONO emissions have increased from 9.4 Tg N in 1980 to 11.5 Tg N in 2016, with a 2.5% average annual rise in the global surface ozone mixing ratio. This increase may lead to overexposure of vegetation to ozone, affecting ecosystem balance and food crop production. Moreover, ozone damage reduces vegetation’s capacity to absorb carbon dioxide, further aggravating greenhouse gas emissions.

The study emphasizes that soil HONO emissions are influenced by nitrogen fertiliser usage and climate factors like soil temperature and water content. Emissions hotspots cluster in agricultural areas worldwide, with Asia being the largest emitter (37.2% of total).

Interestingly, regions with lower pollution levels are more affected by ozone formation due to higher volatile organic compound concentrations and lower nitrogen oxide levels. This implies that as global anthropogenic emissions decrease, the impact of soil HONO emissions on ozone levels may increase.

To mitigate this issue, Prof. Tao Wang recommends considering soil HONO emissions in strategies for reducing global air pollution. The research team developed a robust parameterisation scheme by integrating advanced modelling techniques and diverse datasets, which can facilitate more accurate assessments of ozone production caused by soil HONO emissions and their impact on vegetation.

Future studies should explore mitigation strategies to optimise fertiliser use while maintaining agricultural productivity, such as deep fertiliser placement and the use of nitrification inhibitors.

The ability to visualize complex chemical reactions has long been a holy grail for scientists. For one particularly pungent protein enzyme called sulfite reductase, this dream has finally become a reality, thanks to the work of Florida State University Professor Elizabeth Stroupe and her former doctoral student Behrouz Ghazi Esfahani.

Sulfite reductase is an enzyme that catalyzes the reduction of sulfite to hydrogen sulfide, which is infamous for its “rotten egg” smell. This reaction occurs in various natural environments, from fruit and vegetable decomposition to sewage treatment facilities and landfills. However, despite its importance, scientists had been unable to capture a clear visual image of the enzyme’s structure – until now.

Using an advanced technique called cryo-electron microscopy (cryo-EM), Stroupe and Ghazi Esfahani were able to visualize the 3D structure of sulfite reductase in unprecedented detail. Cryo-EM allows scientists to capture images of chemical reactions as they occur, providing the necessary data to reconstruct the complex molecular structures.

The resulting image is a striking representation of the protein’s intricate arrangement of atoms and electron transfer mechanisms. Stroupe describes it as an “octopus with four yo-yos” due to its flexibility and dynamic nature.

This breakthrough has significant implications for scientists, particularly in understanding how to control or manipulate chemical reactions – a process crucial for drug manufacturers and industry. As Ghazi Esfahani notes, the research also has environmental implications, such as understanding how bacteria use sulfur as an energy source.

While this achievement marks a major step forward in understanding sulfite reductase, there are still unanswered questions about its function as part of larger protein assemblies and how similar enzymes work in other organisms – like the pathogen that causes tuberculosis. Stroupe’s lab is continuing to explore these mysteries, shedding more light on the intricate chemistry of sulfur metabolism.

In conclusion, the ability to visualize complex chemical reactions has finally been achieved for sulfite reductase, thanks to the innovative use of cryo-EM by Stroupe and Ghazi Esfahani. This breakthrough opens doors to new understanding and manipulation of chemical reactions – with far-reaching implications for science, industry, and the environment.

Wildfires have become an increasing threat in the Western United States, with devastating effects on both public health and the environment. As these fires rage, they release enormous amounts of aerosols into the atmosphere, which can travel far and wide, impacting air quality and human health. A recent study, published in Environmental Science: Atmospheres, has shed light on the alarming consequences of wildfire smoke on air quality and the planet’s short-term weather.

The research, led by scientists Siying Lu and Andrey Khlystov from the Desert Research Institute (DRI), monitored air quality in Reno, Nevada over a 19-month period between 2017 and 2020. During this time, more than 106 wildfires impacted the city’s air, with smoke accounting for up to 65% of PM2.5 concentrations and 26% of carbon monoxide levels.

The findings reveal that fine aerosols (PM2.5), which can travel deep into lungs, increased significantly during smoky days. These particles are produced when trees and homes burn, releasing soot and other pollutants into the air. The data also showed that larger aerosols can promote cloud formation and duration by acting as nuclei for water vapor to condense around.

Furthermore, the study found higher concentrations of carbon monoxide present in Reno’s air during smoky days. This gas can reduce the ability of blood to carry oxygen to the brain and other organs. In contrast, levels of nitrogen oxides and ozone remained relatively stable during both smoky and average days.

The research team used a combination of equipment on DRI’s roof and data from a downtown Reno EPA air monitoring station to collect hourly concentrations of PM2.5, ozone, carbon monoxide, and other air pollutants. They also employed satellite images and fire location information from NASA and NOAA to verify when air pollution was caused by wildfire smoke.

The implications of this study are far-reaching. The findings suggest that wildfires can have a significant impact on local air quality, with potential effects on public health and the environment. As wildfires continue to increase in frequency and severity, it is essential to understand their impact on air quality and develop strategies to mitigate these effects.

In conclusion, the study highlights the importance of monitoring air quality during smoky days and provides valuable insights into the consequences of wildfire smoke on human health and the planet’s short-term weather. As we continue to face the challenges posed by wildfires, it is crucial that we prioritize air quality research and public health messaging to ensure a safer and healthier environment for all.