CARIBIC (Civil Aircraft for the Regular Investigation of the Atmosphere Based on an Instrument Container) resumed regular measurement flights with an extended scientific payload in December 2004. ...After an automated measurement container was successfully deployed on intercontinental flights using a Boeing 767 from 1997 to 2002, a far more powerful package now is deployed using a new Airbus A340‐600 made available by Lufthansa German Airlines (Star Alliance). The new CARIBIC system will help address a range of current atmospheric science questions during its projected lifetime of 10 years.
European and Japanese scientists are developing a variety of atmospheric chemistry research and monitoring projects based on the use of passenger aircraft. This is a logical approach with a main advantage being that near‐global coverage is obtained, in contrast to limited coverage through research aircraftbased expeditions. Moreover, highly detailed and consistent data sets can be acquired, as compared to satellite observations in general. In addition, even compared to land‐based observatories, operational costs are moderate.
This review presents how the boreal and the tropical forests affect the atmosphere, its chemical composition, its function, and further how that affects the climate and, in return, the ecosystems ...through feedback processes. Observations from key tower sites standing out due to their long-term comprehensive observations: The Amazon Tall Tower Observatory in Central Amazonia, the Zotino Tall Tower Observatory in Siberia, and the Station to Measure Ecosystem-Atmosphere Relations at Hyytiäla in Finland. The review is complemented by short-term observations from networks and large experiments. The review discusses atmospheric chemistry observations, aerosol formation and processing, physiochemical aerosol, and cloud condensation nuclei properties and finds surprising similarities and important differences in the two ecosystems. The aerosol concentrations and chemistry are similar, particularly concerning the main chemical components, both dominated by an organic fraction, while the boreal ecosystem has generally higher concentrations of inorganics, due to higher influence of long-range transported air pollution. The emissions of biogenic volatile organic compounds are dominated by isoprene and monoterpene in the tropical and boreal regions, respectively, being the main precursors of the organic aerosol fraction. Observations and modeling studies show that climate change and deforestation affect the ecosystems such that the carbon and hydrological cycles in Amazonia are changing to carbon neutrality and affect precipitation downwind. In Africa, the tropical forests are so far maintaining their carbon sink. It is urgent to better understand the interaction between these major ecosystems, the atmosphere, and climate, which calls for more observation sites, providing long-term data on water, carbon, and other biogeochemical cycles. This is essential in finding a sustainable balance between forest preservation and reforestation versus a potential increase in food production and biofuels, which are critical in maintaining ecosystem services and global climate stability. Reducing global warming and deforestation is vital for tropical forests.
The Zeppelin Observatory (78.90∘ N, 11.88∘ E) is located on Zeppelin Mountain at 472 m a.s.l. on
Spitsbergen, the largest island of the Svalbard archipelago. Established in
1989, the observatory is ...part of Ny-Ålesund Research Station and
an important atmospheric measurement site, one of only a few in the high
Arctic, and a part of several European and global monitoring programmes and
research infrastructures, notably the European Monitoring and Evaluation
Programme (EMEP); the Arctic Monitoring and Assessment Programme (AMAP); the
Global Atmosphere Watch (GAW); the Aerosol, Clouds and Trace Gases
Research Infrastructure (ACTRIS); the Advanced Global Atmospheric Gases
Experiment (AGAGE) network; and the Integrated Carbon Observation System
(ICOS). The observatory is jointly operated by the Norwegian Polar Institute
(NPI), Stockholm University, and the Norwegian Institute for Air Research
(NILU). Here we detail the establishment of the Zeppelin Observatory
including historical measurements of atmospheric composition in the European
Arctic leading to its construction. We present a history of the measurements
at the observatory and review the current state of the European Arctic
atmosphere, including results from trends in greenhouse gases,
chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), other
traces gases, persistent organic pollutants (POPs) and heavy metals,
aerosols and Arctic haze, and atmospheric transport phenomena, and provide
an outline of future research directions.
We report emissions of mass, light absorption, particle number, chemical composition and size-resolved organic species from an industrial boiler that burned natural gas and residual oil. Organic ...compounds detected from oil combustion are mainly alkanes; it is not a major source of identifiable polyaromatic hydrocarbons. Elemental carbon (EC) and organic carbon (OC) make up approximately 38% and 15% of the particles from oil burning, respectively. Mass emissions from natural gas were below detection limits. A number peak of ultrafine aerosol (diameters lower than 10
nm) was always associated with oil burning. Burning at full power produced the greatest number of particles in the accumulation mode. Natural gas also produced fine particles, but at a much lower rate. The emission rate of light-absorbing particles from this relatively new boiler is lower than that in current emission inventories. However, real-time measurements show a large contribution to emitted light absorption from boiler warm-up and transients, even those with very short durations. The measured absorption is best explained with a constant absorption cross-section for EC, rather than predictions based on size distribution or mixed aerosol; this finding is consistent with EC in fractal-aggregate form. We compare the emissions with those of a lignite stoker, which this boiler replaced during environmental cleanup in the mid-1990s. Emissions of mass, light absorption and particles are lowest from natural gas, but the oil boiler is also a substantial improvement: emissions of particulate matter are 100 times lower, and emitted absorption is three times lower. However, the oil-burning emissions have a greater net warming effect per mass than those of the lignite plant.
The Parasol Effect on Climate Crutzen, Paul J.; Ramanathan, V.; Anderson, Theodore L. ...
Science (American Association for the Advancement of Science),
12/2003, Volume:
302, Issue:
5651
Journal Article
Atmospheric science. Climate forcing by aerosol--a hazy picture Anderson, Theodore L; Charlson, Robert J; Schwartz, Stephen E ...
Science (American Association for the Advancement of Science),
2003-May-16, 20030516, Volume:
300, Issue:
5622
Journal Article
Measurements of the scavenging efficiency of aerosol particles in fog are presented. The scavenging efficiency as a function of size for accumulation-mode particles is presented, along with ...efficiencies for the total number, accumulation-mode number, and accumulation-mode volume. Particles below ca. 0.3 μm diameter were not efficiently scavenged in the fogs. The scavenging efficiency for accumulation-mode particles showed two steps, indicating that the hygroscopic/hydrophobic nature of the aerosol appeared to have been a controlling factor in determining scavenging efficiencies. Observed changes in the aerosol size distributions are discussed in reference to the processes (i.e., in-cloud scavenging, aqueous-phase reactions) potentially influencing them.
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