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Browsing by Author "Hirst, Edwin"
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Incidence of rough and irregular atmospheric ice particles from Small Ice Detector 3 measurements
Ulanowski, Zbigniew; Kaye, Paul H.; Hirst, Edwin; Greenaway, Richard; Cotton, Richard J.; Hesse, Evelyn; Collier, Christopher T. (2013)The knowledge of properties of ice crystals such as size, shape, concavity and roughness is critical in the context of radiative properties of ice and mixed phase clouds. Limitations of current cloud probes to measure these ... -
Light scattering by ice particles in the Earth's atmosphere and related laboratory measurements
Ulanowski, Zbigniew; Kaye, Paul H.; Hirst, Edwin; Greenaway, Richard (University of Helsinki, 2010)The microphysical properties of ice crystals, such as size, shape, concavity and roughness, are important in the context of radiative properties of ice and mixed phase clouds. Limitations of current cloud probes to measure ... -
Method and Apparatus for the Real-time Characterisation of Particles Suspended within a Fluid Medium.
Particle Instruments and diagnostics; Kaye, Paul H.; Hirst, Edwin (2001-03-06)This invention describes a method by which microparticles, typically in the size range from 0.3um to 100um, which are carried in a fluid suspension, may be rapidly detected and characterized. The method primarily relates ... -
A Miniature Airborne Particle Classifier (APC)
Stopford, Chris; Kaye, Paul H.; Hirst, Edwin; Ulanowski, Zbigniew (2011-09-04)The single greatest source of uncertainty in the estimates of climate sensitivity to either natural or man-made changes continues to be clouds (IPCC 2001, 2007). Much of this uncertainty arises from the lack of information ... -
Miniature, low-cost optical particle counters
Ulanowski, Joseph; Kaye, Paul H.; Hirst, Edwin; Wieser, Andreas; Stanley, Warren (2013)A range of miniature, low-cost optical particle counters for characterizing atmospheric particles has been developed. They are intended for use with disposable balloon-borne radiosondes, dropsondes or in dense ground-based ... -
PHIPS-HALO: The airborne Particle Habit Imaging and Polar Scattering probe-Part 1: Design and operation
Abdelmotaleb, Ahmed; Järvinen, Emma; Duft, D; Hirst, Edwin; Vogt, Steffen; Leisner, T.; Schnaiter, Martin (Copernicus Publications, 2016-07-20)The number and shape of ice crystals present in mixed-phase and ice clouds influence the radiation properties, precipitation occurrence and lifetime of these clouds. Since clouds play a major role in the climate system, ... -
Quasi-spherical ice in convective clouds
Järvinen, Emma; Schnaiter, Martin; Mioche, Guillaume; Jourdan, Olivier; Shcherbakov, Valery N.; Costa, Anja; Afchine, Armin; Krämer, Martina; Heidelberg, Fabian; Jurkat, Tina; Voigt, Christiane; Schlager, Hans; Nichman, Leonid; Gallagher, Martin; Hirst, Edwin; Schmitt, Carl; Bansemer, Aaron; Heymsfield, Andy; Lawson, Paul; Tricoli, Ugo; Pfeilsticker, Klaus; Vochezer, Paul; Möhler, Ottmar; Leisner, Thomas (2016-09-21)Homogeneous freezing of supercooled droplets occurs in convective systems in low and midlatitudes. This droplet-freezing process leads to the formation of a large amount of small ice particles, so-called frozen droplets, ... -
Radiosonde aerosol counter for vertical profiling of atmospheric dust
Ulanowski, Joseph; Hirst, Edwin; Kaye, Paul H.; Harrison, R.G.; Nicoll, K.A.; Rogers, George (2010)A low-cost, miniature aerosol particle counter has been developed, intended for use with balloon-borne meteorological radiosondes. It is particularly suitable for airborne mineral dust measurements. Ambient air is drawn ... -
Real-time detection of airborne asbestos by light scattering from magnetically re-aligned fibers
Stopford, Chris; Kaye, Paul H.; Greenaway, Richard; Hirst, Edwin; Ulanowski, Zbigniew; Stanley, Warren (2013-05)Inadvertent inhalation of asbestos fibers and the subsequent development of incurable cancers is a leading cause of work-related deaths worldwide. Currently, there is no real-time in situ method for detecting airborne ... -
Retrieving the size of particles with rough and complex surfaces from two-dimensional scattering patterns
Ulanowski, Zbigniew; Hirst, Edwin; Kaye, Paul H.; Greenaway, Richard (2012-12)Scattered intensity measurement is a commonly used method for determining the size of small particles. However, it requires calibration and is subject to errors due to changes in incident irradiance or detector sensitivity. ... -
Retrieving the size of particles with rough surfaces from 2D scattering patterns
Ulanowski, Zbigniew; Kaye, Paul H.; Hirst, Edwin; Greenaway, Richard (2011)Scattered intensity measurement is a commonly used method for determining the size of small particles. However, it requires calibration and is subject to errors due to changes in incident irradiance or detector sensitivity. ... -
Rough and irregular ice crystals in mid-latitude clouds
Ulanowski, Zbigniew; Kaye, Paul H.; Hirst, Edwin; Greenaway, Richard S.; Cotton, Richard (2012-07) -
Simultaneous light scattering and intrinsic fluorescence measurement for bioaerosol detection
Barton, J.E.; Hirst, Edwin; Kaye, Paul H.; Clark, J.M. (2000)Several workers have reported the development of systems which allow the measurement of intrinsic fluorescence from particles irradiated with ultra-violet radiation; see for example, Hairston et al (1997); Seaver et al. ... -
Simultaneous light scattering and intrinsic fluorescence measurement for the classification of airborne particles
Kaye, Paul H.; Barton, J.E.; Hirst, Edwin; Clark, J.M. (2000)We describe a prototype laboratory light-scattering instrument that integrates two approaches to airborne particle characterization: spatial light-scattering analysis and intrinsic fluorescence measurement, with the aim ... -
Simultaneous radar and aircraft observations of mixed-phase cloud at the 100m scale
Field, P.R.; Hogan, R.J.; Brown, P.R.A.; Illingworth, A.J.; Choularton, T.W.; Kaye, Paul H.; Hirst, Edwin; Greenaway, Richard (2004)Three UK C-130 aircraft flights performed in conjunction with the Chilbolton Advanced Meteorological Radar were carried out in mixed-phase clouds. The aircraft instrumentation included the Small Ice Detector (SID) and ... -
A Universal Cloud and Aerosol Sounding System (UCASS) based on wide angle light scattering
Smith, Helen; Ulanowski, Zbigniew; Stanley, Warren; Kaye, Paul; Hirst, Edwin (2016-04-05)Summary This presentation discusses a new optical particle counter design, developed at the Centre for Atmospheric and Instrumentation Research, University of Hertfordshire. The Universal Cloud and Aerosol Sounding System ... -
The Universal Cloud and Aerosol Sounding System (UCASS): a low-cost miniature optical particle counter for use in dropsonde or balloon-borne sounding systems
Smith, Helen R.; Ulanowski, Joseph; Kaye, Paul H.; Hirst, Edwin; Stanley, Warren; Kaye, Richard; Wieser, Andreas; Stopford, Chris; Kezoudi, Maria; Girdwood, Joseph; Greenaway, Richard; MacKenzie, A Robert (2019-12-13)A low-cost miniaturized particle counter has been developed by The University of Hertfordshire (UH) for the measurement of aerosol and droplet concentrations and size distributions. The Universal Cloud and Aerosol Sounding ...