Highlight articles

Impact of climate and land cover changes on tropospheric ozone air quality and public health in East Asia between 1980 and 2010

Historical land cover and land use change alone between 1980 and 2010 could lead to reduced summertime surface ozone by up to 4ppbv in East Asia. Climate change alone could lead to an increase in summertime ozone by 2-10ppbv in most of East Asia. Land cover change could offset part of the climate effect and lead to a previously unknown public health benefit. The sensitivity of surface ozone to land cover change is more dependent on dry deposition than isoprene emission in most of East Asia.

Past changes in the vertical distribution of ozone – Part 3: Analysis and interpretation of trends

Trends in the vertical distribution of ozone are reported for new and recently revised data sets. The amount of ozone-depleting compounds in the stratosphere peaked in the second half of the 1990s. We examine the trends before and after that peak to see if any change in trend is discernible. The previously reported decreases are confirmed. Furthermore, the downward trend in upper stratospheric ozone has not continued. The possible significance of any increase is discussed in detail.

Technological shifts between fuel sources have had unexpected impacts on atmospheric composition and these significant changes can go undetected if source-specific monitoring infrastructure is not in place. We present chemically comprehensive, continuous measurements of organic compounds in a developed megacity (London), that show diesel-related hydrocarbons can dominate reactive carbon and ozone formation potential, highlighting a serious underestimation of this source in emission inventories.

Tropospheric ozone and its precursors from the urban to the global scale from air quality to short-lived climate forcer

Ozone holds a certain fascination in atmospheric science. It is ubiquitous in the atmosphere, central to tropospheric oxidation chemistry, and yet harmful to human and ecosystem health as well as being an important greenhouse gas. It is not emitted into the atmosphere but is a byproduct of the very oxidation chemistry it largely initiates. This review examines current understanding of the processes regulating tropospheric ozone at global to local scales from both measurements and models.

Mapping gas-phase organic reactivity and concomitant secondary organic aerosol formation: chemometric dimension reduction techniques for the deconvolution of complex atmospheric data sets

This paper describes a new ensemble methodology for the statistical analysis of atmospheric gas- & particle-phase composition data sets. The methodology reduces the huge amount of data derived from many chamber experiments to show that organic reactivity & resultant particle formation can be mapped into unique clusters in statistical space. The model generated is used to map more realistic plant mesocosm oxidation data, the projection of which gives insight into reactive pathways & precursors.

Reliable, robust and realistic: the three R’s of next-generation land-surface modelling

Land surface models (LSMs) describe how carbon and water fluxes react to environmental change. They are key component of climate models, yet they differ enormously. Many perform poorly, despite having many parameters. We outline a development strategy emphasizing robustness, reliability and realism, none of which is guaranteed by complexity alone. We propose multiple constraints, benchmarking and data assimilation, and representing unresolved processes stochastically, as tools in this endeavour.

Rapid transport of East Asian pollution to the deep tropics

We use observations and model calculations to show that “cold surges” occurring during Northern Hemisphere winter can rapidly transport East Asian pollution to equatorial Southeast Asia. As well as affecting atmospheric composition near the surface, we argue that strong convection can subsequently lift the polluted air masses to the tropical upper troposphere. This suggests a potentially important connection between midlatitude pollution sources and the lower stratosphere.

Intercomparison of vertically resolved merged satellite ozone data sets: interannual variability and long-term trends

Understanding ozone trends in the vertical are vital in terms of assessing the success of the Montreal Protocol. This paper compares and analyses the long-term trends in stratospheric ozone from seven new merged satellite data sets. The data sets largely agree well with each other, particularly for the negative trends seen in the early period 1984-1997. For the 1998-2011 period there is less agreement, but a clear shift from negative to mostly positive trends.

Persistent after-effects of heavy rain on concentrations of ice nuclei and rainfall suggest a biological cause

We show that atmospheric load of ice nuclei is enhanced for up to 20 days after key rainfall events. The rate of enhancement decreases exponentially with time. Rainfall quantity and frequency are increased for a similar duration and with similar exponential decreases thereby supporting the notion of rainfall feedback. We reveal series of significant feedback in rainfall patterns across Australia over the past century and marked changes in feedback patterns, and we indicate their locations.

Identification and quantification of gaseous organic compounds emitted from biomass burning using two-dimensional gas chromatography–time-of-flight mass spectrometry

This work represents the first application of two-dimensional gas chromatography to broadly characterize the gas-phase emissions of biomass burning, including comparisons among the emissions from burns of selected conifer, grass, crop residue, and peat fuel types. In these smoke samples, over 700 compounds were detected, which are discussed in the context of potential secondary organic aerosol formation.

News & press Highlight articles

Highlight articles

Information for

External links