Genera: Altostratus – Greyish or bluish cloud sheet or layer of striated, fibrous or uniform appearance, totally or partly covering the sky and having parts thin enough to reveal the sun at least vaguely, as through ground glass. Altostratus is composed of water droplets and ice crystals; the cloud also contains raindrops and snowflakes. Altostratus is nearly always of great horizontal extent (up to hundreds of kilometers) and of fairly considerable vertical extent (up to thousands of metres). It may be composed of two or more superposed layers at slightly different levels, sometimes partly merged. Altostratus is generally so dense that even through its thinner parts, the sun is seen only vaguely. The thicker parts may be dense enough to mask the sun completely. Altostratus is a percipitating cloud. The precipitation may be seen in form of virga trailing from the cloud base. When precipitation from Altostratus reaches the ground, it is usually of the “continuous type” and in the form of rain, snow or ice pellets.
Rod: Altostratus – Sivkasta ili plavicasta oblacna plahta ili veo/sloj vlaknastog, izbrazdanog ili uniformnog izgleda koji djelimicno ili u potpunosti prekriva nebo. Neki njegovi dijelovi su dovoljno tanki da otkrivaju sunce barem da se nazire, kao da ga gledate kroz pjeskareno staklo. Altostratus se sastoji od od kapljica vode i ledenih kristala; ovaj oblak takodjer sadrzi i kisne kapljice te snijezne pahulje. Altostratus je skoro pa uvijek ogromnog horizontalnog razvoja (do vise stotina kilometara) te od prilicno znacajnog vertikalnog razvoja (do vise stotina metara). Moze se sastojati od dva sloja koja leze jedan na drugome na nesto razlicitim nivoima, ponekada djelomicno spojeni. Altostratus je obicno tako gust da se cak i kroy njegove tanje dijelove sunce slabo vidi. Deblji dijelovi su dovoljno neprobojni da mogu u potpunosti zamaskirati sunce. Altostratus daje padavine. Padavine mogu biti opazene u vidu virge koja sa spusta od baze oblaka. Kada padavine iz Altostratusa dopru do zemlje, najcesce je rijec o “kontinuiranom tipu” i to u vidu kise, snijega ili ledenih kuglica.
Species: No subdivision into species.
Vrste: Nema podjela ovog oblaka na vrste.
Variety: Undulatus – From the Latin undulatus, which means having waves, waved; from undula, diminutive of unda, which means wave.
Podvrsta: Undulatus – Od latinske rijeci undulatus, sto znaci biti talasast, valovit; od undula, umanjenice od unda, sto znaci val.
Definition of a cloud:
A cloud is a visible aggregate of minute particles of water or ice, or of both, in the free air. This aggregate may include larger particles of water or ice and particles, such as those present in fumes, smoke or dust.
Definicija oblaka: Oblak je vidljivo agregatno stanje zasicenih cestica vode, leda ili vode i leda, koje se nalaze slobodne u zraku. Mogu biti u pitanju i krupnije cestice vode i leda i cestice poput onih koje su prisutne u dimu, isparenjima ili prasini.
Appearance of clouds:
The appearance of a cloud is determined by the nature, sizes, number and distribution in space of its constituent particles. Appearance is best described in terms of dimensions, shape, structure, texture, luminance and colour of the cloud.
Pojava oblaka tj. njihov izgled je odredjen karakterom, velicinama, kolicinom i raspodjelom cestica koje ga sacinjavaju kroz prostor. Izgled oblaka je najbolje opisan u kroz dimenzije, oblik, strukturu, teksturu, osvjetljenost i boju oblaka.
Classification of clouds:
A classification of the charcteristic forms of clouds, in terms of “genera”, “species” and “varieties” has been established by the WMO(World Meteorological Organisation).
Klasifikacija karakteristicnih oblika oblaka u smislu “rodova”, “vrsta” i “podvrsta” je ostvarena od strane WMO (World Meteorological Organisation) tj. Svjetske Meteoroloske Organizacije.
(I) Genera
The classification is essentially based on 10 main groups, called genera, which are mutually exclusive, that is to say, a given cloud can belong to one genus only. The genera are;
Podjela na rodove je ustvari podjela na 10 osnovnih grupa zvanih rodovi koji su medjusobno posebni, sto znaci da odredjeni oblak moze da pripada samo jednom rodu. Podjela na rodove je slijedeca:
Cirrus – Ci
Cirrocumulus – Cc
Cirrostratus – Cs
Altocumulus -Ac
Altostratus -As
Nimbostratus -Ns
Stratocumulus – Sc
Stratus – St
Cumulus – Cu
Cumulonimbus – Cb
(II) Species
Obseved peculiarities in the shape of clouds and differences in their internal structure have led to the subdivision of most of the cloud genera into species.
Osmotrene pojedinosti u obliku oblaka i njihovih razlika u unutarnjoj strukturi su doveli do podjele vecine rodova oblaka na vrste.
(III) Varieties
Clouds may exhibit special characteristics which determine their variety. These characteristics are related to the different arrangements of the could elements.
Oblaci mogu iskazati posebne karakteristike koje ce da odrede njihove podvrste. Te karakteristike su u vezi sa razlicitim rasporedom elementa oblaka.
(IV) Supplementary cloud features
Dopunske odlike i oblaci pratioci:
1. incus – inc
2. mamma – mam
3. virga – vir
4. praecipitatio – pra
5. arcus – arc
6. tuba – tub
7. pileus – pil
8. velum – vel
9. pannus – pan
