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International Cloud Atlas
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Introduction
Foreword to the 2017 edition
Meteorological definition of a meteor
General classification of meteors
Hydrometeors
Lithometeors
Photometeors
Electrometeors
Clouds
Introduction and principles of cloud classification
Definition of a cloud
Appearance of clouds
Principles of cloud classification
Cloud classification summary
Cloud abbreviations and symbols
Definitions of clouds
Useful concepts
Definitions of clouds
Descriptions of clouds
Cirrus (Ci)
Cirrocumulus (Cc)
Cirrostratus (Cs)
Altocumulus (Ac)
Altostratus (As)
Nimbostratus (Ns)
Stratocumulus (Sc)
Stratus (St)
Cumulus (Cu)
Cumulonimbus (Cb)
Orographic influences on clouds
Introduction
Orographic influence on the windward side
Orographic influence on the leeward side
Upper atmospheric clouds
Nacreous clouds
Nitric acid and water polar stratospheric clouds
Noctilucent clouds (polar mesospheric clouds)
Other Meteors
Classification and symbols of meteors other than clouds
Hydrometeors
Lithometeors
Photometeors
Electrometeors
Character and intensity of precipitation
Additional symbols
Definitions and descriptions of meteors other than clouds
Hydrometeors other than clouds
Lithometeors
Photometeors
Electrometeors
Observation of meteors other than clouds from the Earth's surface
Introduction
Observation of hydrometeors other than clouds
Observation of lithometeors
Observation of photometeors
Observation of electrometeors
Observing Clouds
Observation of clouds from the earth's surface
Introduction
Identifying clouds
Total cloud cover and cloud amount
Height and altitude
Direction and speed of movement
Optical thickness
Observation of clouds from mountain stations
Observation of upper atmospheric clouds
Coding of clouds in the codes C
L
, C
M
and C
H
and corresponding symbols
Introduction of the coding of clouds
Code specifications and coding procedures
Coding instructions of clouds in the codes C
L
, C
M
and C
H
Cloud classification aids C
L
, C
M
and C
H
Cloud symbols corresponding to the C
L
, C
M
and C
H
codes
Observation of clouds from aircraft
Issues for observation of clouds from aircraft
Descriptions of clouds as observed from aircraft
Fog and haze as seen from aircraft
Images
Search Image Gallery
Compare two images
Glossary
Other Information
Editorial note
Appendix 1 - Etymology of latin names of clouds
Appendix 2 - Historical bibliography of cloud classification
Appendix 3 - History of cloud nomenclature
Appendix 4 - Lists of tables, figures and acronyms
History of the ICA
Foreword to the 1987 edition of volume II
Preface to the 1975 edition of volume I
Preface to the 1956 edition
Preface to the 1939 edition
Previous Editions
ICA Vol. 2 (1987 edition)
ICA Vol. 1 (1975 edition)
ICA Vol. 1 (1956 edition)
ICA (1930 edition)
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Clouds
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Descriptions of clouds
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Altostratus (As)
>
Varieties
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Altostratus undulatus (As un)
Clouds
Introduction and principles of cloud classification
Definitions of clouds
Descriptions of clouds
Cirrus (Ci)
Cirrocumulus (Cc)
Cirrostratus (Cs)
Altocumulus (Ac)
Altostratus (As)
Definition
Species
Varieties
Altostratus translucidus (As tr)
Altostratus opacus (As op)
Altostratus duplicatus (As du)
Altostratus undulatus (As un)
Altostratus radiatus (As ra)
Supplementary features and accessory clouds
Clouds from which Altostratus may form
Main differences between Altostratus and similar clouds of other genera
Physical constitution
Explanatory remarks
Nimbostratus (Ns)
Stratocumulus (Sc)
Stratus (St)
Cumulus (Cu)
Cumulonimbus (Cb)
Orographic influences on clouds
Upper atmospheric clouds
Altostratus undulatus (As un) -
Clayton 1896
,
CEN 1930
(Section 2.3.5.3.4)
Altostratus showing undulations.
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