Researchers from the University’s Department of Chemistry found evidence for an atmospheric chemical equator around 50 km wide in cloudless skies in the Western Pacific. Their findings show for the first time that the chemical and meteorological boundaries between the two air masses are not necessarily the same.
The discovery will provide important clues to help scientists to model simulations of the movement of pollutants in the atmosphere more accurately, and to assess the impact of pollution on climate. The study is part of the ACTIVE project (Aerosol and Chemical Transport in Tropical Convection) funded by the Natural Environment Research Council.
Previously, scientists believed that the Intertropical Convergence Zone (ITCZ) formed the boundary between the polluted air of the Northern Hemisphere and the cleaner air of the Southern Hemisphere. The ITCZ is a cloudy region circling the globe where the trade winds from each hemisphere meet. It is characterised by rapid vertical uplift and heavy rainfall, and acts as a meteorological barrier to pollutant transport between the hemispheres.
But the new research, to be published in the Journal of Geophysical Research - Atmospheres, found huge differences in air quality on either side of the chemical equator, which was 50 km wide and well to the north of the ITCZ. The study revealed that carbon monoxide, a tracer of combustion, increased from 40 parts per billion to the south, to 160 parts per billion in the north. The difference in pollutant levels was increased by extensive forest fires to the north of the boundary and very clean air south of the chemical equator being pulled north from the Southern Indian Ocean by a land based cyclone in northern Australia.
The scientists discovered evidence of the chemical equator using sensors on a specially equipped aeroplane during a series of flights north of Darwin. At the time, the ITCZ was situated well to the south over central Australia.
Dr Jacqueline Hamilton, of the Department of Chemistry at York, said: "The shallow waters of the Western Pacific, known as the Tropical Warm Pool, have some of highest sea surface temperatures in the world, which result in the region’s weather being dominated by storm systems. The position of the chemical equator was to the south of this stormy region during the ACTIVE campaign.
"This means that these powerful storms may act as pumps, lifting highly polluted air from the surface to high in the atmosphere where pollutants will remain longer and may have a global influence. To improve global simulations of pollutant transport, it is vital to know when the chemical and meteorological boundary are in different locations."
The York researchers were part of a team, including scientists from the universities of Manchester and Cambridge, that studied transport of pollutants in the Western Pacific. The ACTIVE project is led by Professor Geraint Vaughan, of the University of Manchester.
The research was funded by the Natural Environment Research Council (NERC). Other partners include the Australian Bureau of Meteorology and Flinders University. Flights were carried out onboard the NERC Airborne Research and Survey Facility Dornier 228 aircraft.
David Garner | alfa
Water - as the underlying driver of the Earth’s carbon cycle
17.01.2017 | Max-Planck-Institut für Biogeochemie
Modeling magma to find copper
13.01.2017 | Université de Genève
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).
Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...
10.01.2017 | Event News
09.01.2017 | Event News
05.01.2017 | Event News
18.01.2017 | Power and Electrical Engineering
18.01.2017 | Materials Sciences
18.01.2017 | Life Sciences