On the scattering behaviour of bullet-rosette and bullet-shaped ice crystals
The scattering behaviour of bullet-rosette and bullet-shaped ice particles is investigated using model calculations (ray tracing method) with special emphasis on the asymmetry factor <i>g</i>. Because the variability of the geometrical features of these particles is very large, some...
| Main Author: | |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
1996-05-01
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| Series: | Annales Geophysicae |
| Online Access: | https://www.ann-geophys.net/14/566/1996/angeo-14-566-1996.pdf |
| _version_ | 1811199466941710336 |
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| author | B. Strauss |
| author_facet | B. Strauss |
| author_sort | B. Strauss |
| collection | DOAJ |
| description | The scattering behaviour of bullet-rosette
and bullet-shaped ice particles is investigated using model calculations (ray
tracing method) with special emphasis on the asymmetry factor <i>g</i>. Because
the variability of the geometrical features of these particles is very large,
some representative shapes are used in the calculations. The model is based on
geometrical optics, and particles are assumed to be oriented randomly; a
wavelength of 0.56 μm is considered; absorption is neglected. The
scattering behaviour of bullet rosettes is compared to that of single branches
out of the bullet rosette. It turns out that there are slight differences in the
asymmetry factor values, depending on the lengths of the branches (∆<i>g</i>~0.02)
and on the angles between the branches (∆<i>g</i>~0.01).
Bullets show some special features in their phase functions due to the pyramid.
The length of the particle influences the asymmetry factor (∆<i>g</i>~0.10),
as does the shape of the pyramid (∆<i>g</i>~0.07). The
influence of the pyramidal shape decreases with increasing particle length.
Bullets were compared to hexagonally shaped columns. This was done for two
columns, one as long as the columnar part of the bullet (length without
pyramid), and one for a column as long as the bullet including the pyramid.
Asymmetry factor values of bullets with a pyramidal angle of 28° deviate less
than ∆<i>g</i>~0.01 from the range given by the two values of
the columns. |
| first_indexed | 2024-04-12T01:48:44Z |
| format | Article |
| id | doaj.art-c33b54a50fc04b048cf9cc36bb1413a2 |
| institution | Directory Open Access Journal |
| issn | 0992-7689 1432-0576 |
| language | English |
| last_indexed | 2024-04-12T01:48:44Z |
| publishDate | 1996-05-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Annales Geophysicae |
| spelling | doaj.art-c33b54a50fc04b048cf9cc36bb1413a22022-12-22T03:53:00ZengCopernicus PublicationsAnnales Geophysicae0992-76891432-05761996-05-011456657310.1007/s00585-996-0566-9On the scattering behaviour of bullet-rosette and bullet-shaped ice crystalsB. StraussThe scattering behaviour of bullet-rosette and bullet-shaped ice particles is investigated using model calculations (ray tracing method) with special emphasis on the asymmetry factor <i>g</i>. Because the variability of the geometrical features of these particles is very large, some representative shapes are used in the calculations. The model is based on geometrical optics, and particles are assumed to be oriented randomly; a wavelength of 0.56 μm is considered; absorption is neglected. The scattering behaviour of bullet rosettes is compared to that of single branches out of the bullet rosette. It turns out that there are slight differences in the asymmetry factor values, depending on the lengths of the branches (∆<i>g</i>~0.02) and on the angles between the branches (∆<i>g</i>~0.01). Bullets show some special features in their phase functions due to the pyramid. The length of the particle influences the asymmetry factor (∆<i>g</i>~0.10), as does the shape of the pyramid (∆<i>g</i>~0.07). The influence of the pyramidal shape decreases with increasing particle length. Bullets were compared to hexagonally shaped columns. This was done for two columns, one as long as the columnar part of the bullet (length without pyramid), and one for a column as long as the bullet including the pyramid. Asymmetry factor values of bullets with a pyramidal angle of 28° deviate less than ∆<i>g</i>~0.01 from the range given by the two values of the columns.https://www.ann-geophys.net/14/566/1996/angeo-14-566-1996.pdf |
| spellingShingle | B. Strauss On the scattering behaviour of bullet-rosette and bullet-shaped ice crystals Annales Geophysicae |
| title | On the scattering behaviour of bullet-rosette and bullet-shaped ice crystals |
| title_full | On the scattering behaviour of bullet-rosette and bullet-shaped ice crystals |
| title_fullStr | On the scattering behaviour of bullet-rosette and bullet-shaped ice crystals |
| title_full_unstemmed | On the scattering behaviour of bullet-rosette and bullet-shaped ice crystals |
| title_short | On the scattering behaviour of bullet-rosette and bullet-shaped ice crystals |
| title_sort | on the scattering behaviour of bullet rosette and bullet shaped ice crystals |
| url | https://www.ann-geophys.net/14/566/1996/angeo-14-566-1996.pdf |
| work_keys_str_mv | AT bstrauss onthescatteringbehaviourofbulletrosetteandbulletshapedicecrystals |