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CCN measurements at the Princess Elisabeth Antarctica research station during three austral summers
For three austral summer seasons (2013-2016, each from December to February) aerosol particles arriving at the Belgian Antarctic research station Princess Elisabeth (PE) in Dronning Maud Land in East Antarctica were characterized. This included number concentrations of total aerosol particles (N CN ) and cloud condensation nuclei (N CCN ), the particle number size distribution (PNSD), the aerosol particle hygroscopicity, and the influence of the air mass origin on N CN and N CCN . In general N CN was found to range from 40 to 6700cm -3 , with a median of 333cm -3 , while N CCN was found to cover a range between less than 10 and 1300cm-3 for supersaturations (SSs) between 0.1% and 0.7%. It is shown that the aerosol is dominated by the Aitken mode, being characterized by a significant amount of small, and therefore likely secondarily formed, aerosol particles, with 94% and 36% of the aerosol particles smaller than 90 and â35nm, respectively. Measurements of the basic meteorological parameters as well as the history of the air masses arriving at the measurement station indicate that the station is influenced by both marine air masses originating from the Southern Ocean and coastal areas around Antarctica (marine events - MEs) and continental air masses (continental events - CEs). CEs, which were defined as instances when the air masses spent at least 90% of the time over the Antarctic continent during the last 10 days prior to arrival at the measurements station, occurred during 61% of the time during which measurements were done. CEs came along with rather constant N CN and N CCN values, which we denote as Antarctic continental background concentrations. MEs, however, cause large fluctuations in N CN and N CCN , with low concentrations likely caused by scavenging due to precipitation and high concentrations likely originating from new particle formation (NPF) based on marine precursors. The application of HYSPLIT back trajectories in form of the potential source contribution function (PSCF) analysis indicate that the region of the Southern Ocean is a potential source of Aitken mode particles. On the basis of PNSDs, together with N CCN measured at an SS of 0.1%, median values for the critical diameter for cloud droplet activation and the aerosol particle hygroscopicity parameter ° were determined to be 110nm and 1, respectively. For particles larger than Äâ°110nm the Southern Ocean together with parts of the Antarctic ice shelf regions were found to be potential source regions. While the former may contribute sea spray particles directly, the contribution of the latter may be due to the emission of sea salt aerosol particles, released from snow particles from surface snow layers, e.g., during periods of high wind speed, leading to drifting or blowing snow. The region of the Antarctic inland plateau, however, was not found to feature a significant source region for aerosol particles in general or page276 for cloud condensation nuclei measured at the PE station in the austral summer
CCN measurements at the Princess Elisabeth Antarctica research station during three austral summers
For three austral summer seasons (2013â2016, each from December to February)
aerosol particles arriving at the Belgian Antarctic research station Princess
Elisabeth (PE) in Dronning Maud Land in East Antarctica were characterized.
This included number concentrations of total aerosol
particles (NCN) and cloud condensation nuclei (NCCN),
the particle number size distribution (PNSD), the aerosol particle
hygroscopicity, and the influence of the air mass origin on NCN
and NCCN. In general NCN was found to range from
40Â to 6700 cmâ3, with a median of 333 cmâ3, while
NCCNÂ was found to cover a range between less than 10Â and
1300 cmâ3 for supersaturations (SSs) between 0.1 % and 0.7 %. It is
shown that the aerosol is dominated by the Aitken mode, being characterized by a
significant amount of small, and therefore likely secondarily formed, aerosol
particles, with 94 % and 36 % of the aerosol particles smaller than
90Â and â35 nm, respectively. Measurements of the basic
meteorological parameters as well as the history of the air masses arriving
at the measurement station indicate that the station is influenced by both
marine air masses originating from the Southern Ocean and coastal areas
around Antarctica (marine events â MEs) and continental air masses
(continental events â CEs). CEs, which were defined as instances when the air
masses spent at least 90 % of the time over the
Antarctic continent during the last 10Â days prior to arrival at the measurements station, occurred during 61 % of the time during which
measurements were done. CEs came along with rather constant NCN
and NCCNÂ values, which we denote as Antarctic continental
background concentrations. MEs, however, cause large fluctuations
in NCN and NCCN, with low concentrations likely caused
by scavenging due to precipitation and high concentrations likely originating
from new particle formation (NPF) based on marine precursors. The application
of HYSPLIT back trajectories in form of the potential source contribution
function (PSCF) analysis indicate that the region of the Southern Ocean is a
potential source of Aitken mode particles. On the basis of PNSDs, together
with NCCNÂ measured at an SS of 0.1 %, median values for the
critical diameter for cloud droplet activation and the aerosol particle
hygroscopicity parameter Îș were determined to be 110 nm and 1,
respectively. For particles larger than â110 nm the Southern Ocean
together with parts of the Antarctic ice shelf regions were found to be
potential source regions. While the former may contribute sea spray particles
directly, the contribution of the latter may be due to the emission of sea salt
aerosol particles, released from snow particles from surface snow layers,
e.g., during periods of high wind speed, leading to drifting or blowing snow.
The region of the Antarctic inland plateau, however, was not found to feature a
significant source region for aerosol particles in general or for cloud condensation nuclei measured at the PEÂ station in
the austral summer.</p
Photosynthesis-dependent isoprene emission from leaf to planet in a global carbon-chemistry-climate model
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Pollution transported by hurricane Ophelia: 3D observations by ground-based, aircraft and satellite data compared with CAMS atmospheric composition analyses
info:eu-repo/semantics/nonPublishe
Pollution Transported By Hurricane Ophelia: Observations By IASI Compared with CAMS Atmospheric Composition Analyses and Other Remote Sensing Data
info:eu-repo/semantics/nonPublishe
The role of data in maximising operational efficiency in shipping
How can data and digitalisation bring new insights to operational efficiency in shipping and help capitalise on the opportunity presented? Our new Insight Brief explores this question as part of a series that examines the undervalued opportunity presented by operational efficiency
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