Inverse modelling of CF4 and NF3 emissions in East Asia Atmospheric Chemistry and Physics DOI 10.5194/acp-18-13305-2018 17 September 2018 Emissions of carbon tetrafluoride CF4, NF3 and CHF3 in east Asia have been calculated using atmospheric measurements and an atmospheric transport model. We calculate emissions of CF4 to be quite constant between the years 2008 and 2015 for both China and South Korea, with 2015 emissions calculated at 4.33 ± 2.65 Gg yr-1 and 0.36 ± 0.11 Gg yr-1, respectively. Emission estimates of NF3 from South Korea could be made with relatively small uncertainty at 0.6 ± 0.07 Gg yr-1 in 2015. Read more
The climate effects of increasing ocean albedo: an idealized representation of solar geoengineering Atmospheric Chemistry and Physics DOI 10.5194/acp-18-13097-2018 12 September 2018 Marine cloud brightening has been proposed as a means of geoengineering/climate intervention, or deliberately altering the climate system to offset anthropogenic climate change. In idealized simulations that highlight contrasts between land and ocean, we find that the globe warms, including the ocean due to transport of heat from land. This study reinforces that no net energy input into the Earth system does not mean that temperature will necessarily remain unchanged. Read more
Radiative feedbacks of dust in snow over eastern Asia in CAM4-BAM Atmospheric Chemistry and Physics DOI 10.5194/acp-18-12683-2018 31 August 2018 This study extends our previous investigation in dust–radiation interactions to investigate SRF and its feedbacks on the regional climate and the dust cycle over east Asia by use of the CAM4-BAM. Our results show that SRF increases the east Asian dust emissions significantly by 13.7 % in the spring, in contrast to −7.6 % of decreased dust emissions by DRF. Hence, a significant feature of SRF on the Tibetan Plateau can create a positive feedback loop to enhance the dust cycle over east Asia. BAM">Read more
Connecting regional aerosol emissions reductions to local and remote precipitation responses Atmospheric Chemistry and Physics DOI 10.5194/acp-18-12461-2018 28 August 2018 Small particles in Earth’s atmosphere (also referred to as atmospheric aerosols) emitted by human activities impact Earth’s climate in complex ways and play an important role in Earth’s water cycle. We use a climate modeling approach and find that aerosols from the United States and Europe can have substantial effects on rainfall in far-away regions such as Africa’s Sahel or the Mediterranean. Air pollution controls in these regions may help reduce the likelihood and severity of Sahel drought. Read more
Extreme levels of Canadian wildfire smoke in the stratosphere over central Europe on 21–22 August 2017 Atmospheric Chemistry and Physics DOI 10.5194/acp-18-11831-2018 20 August 2018 Extremely large light extinction coefficients of 500 Mm-1, about 20 times higher than after the Pinatubo volcanic eruptions in 1991, were observed by EARLINET lidars in the stratosphere over central Europe from 21 to 22 August, 2017. This paper provides an overview based on ground-based (lidar, AERONET) and satellite (MODIS, OMI) remote sensing. Read more
Formation and evolution of tar balls from northwestern US wildfires Atmospheric Chemistry and Physics DOI 10.5194/acp-18-11289-2018 13 August 2018 This paper presents the first direct atmospheric observations of the formation and evolution of tar balls (TBs) in forest fires collected during the Department of Energy’s Biomass Burning Observation Project (BBOP). We quantify, for the first time, the TB mass fraction in the BB plumes and show that this mass fraction increases from less than 1 % to 50 % within the first couple of hours of plume aging. Using Mie theory we find that TBs are consistent with being weak light absorbers. Read more
HTAP2 multi-model estimates of premature human mortality due to intercontinental transport of air pollution and emission sectors Atmospheric Chemistry and Physics DOI 10.5194/acp-18-10497-2018 23 July 2018 Emissions from one continent affect air quality and health elsewhere. Here we quantify the effects of intercontinental PM2.5 and ozone transport on human health using a new multi-model ensemble, evaluating the health effects of emissions from six world regions and three emission source sectors. Emissions from one region have significant health impacts outside of that source region; similarly, foreign emissions contribute significantly to air-pollution-related deaths in several world regions. Read more
Mineralogy and physicochemical features of Saharan dust wet deposited in the Iberian Peninsula during an extreme red rain event Atmospheric Chemistry and Physics DOI 10.5194/acp-18-10089-2018 16 July 2018 Saharan dust wet deposited in Granada (Spain) on 21–23 February 2017 during the most extreme red rain event of the last decades led to the deposition of ~ 140 000 T of dust just in the city of Granada, dwarfing any other standard Saharan dust events taking place in the area. The multianalytical study of Saharan dust disclosed potential source areas and the mineralogy and composition of the size fractions of desert dust as well as its potential biogeochemical, radiative, and health effects. Read more
The diurnal cycle of cloud profiles over land and ocean between 51°S and 51°N, seen by the CATS spaceborne lidar from the International Space Station Atmospheric Chemistry and Physics DOI 10.5194/acp-18-9457-2018 6 July 2018 From 3 years of observations from the CATS lidar on the International Space Station we document the daily cycle of the vertical distribution of clouds. This is the first time this is documented over several continents and oceans using finely resolved measurements on a near-global scale from a single instrument. We show that other instruments observing clouds from space, like CALIPSO, document extremes of the daily cycle over ocean and closer to the average over land. CATS spaceborne lidar from the International Space Station">Read more
Transboundary ozone pollution across East Asia: daily evolution and photochemical production analysed by IASI + GOME2 multispectral satellite observations and models Atmospheric Chemistry and Physics DOI 10.5194/acp-18-9499-2018 6 July 2018 This paper tackles a major issue for air quality over East Asia: ozone pollution produced over a major source, like the North China Plain, and the contribution of ozone produced while being transported across the continent and the surrounding seas. The main originality of the paper lays in the fact that this photochemical production of ozone is observationally quantified with new multispectral satellite observations offering unique skills to observe the ozone pollution plumes near the surface. IASI + GOME2 multispectral satellite observations and models">Read more