Clouds 101: A Newly Classified Cloud Undulatus Asperatus

Undulatus Asperatus

The cloud type was first identified in 2006 in Cedar Rapids, Iowa and then in 2009. it was proposed by the founder of the Cloud Appreciation Society to list a new cloud formation named Undulatus asperatus, or simply asperatus. It made the cut and asperatus was the first cloud formation added since 1951. (when cirrus intortus was added) to the International Cloud Atlas of the World Meteorological Organization(WMO).

Ova vrsta oblaka je prvi put identifikovana 2006. godine u Cedar Rapidsu, drzava Iowa, a 2009. godine je predlozeno od strane osnivaca Cloud Appreciation Society-a da se zavede nova formacija oblaka pod imenom Undulatus asperatus ili jednostavnije samo asperatus. Prijedlog je prosao i asperatus je bio prvi oblak koji je zvanicno dodan jos od 1951. godine kada je Cirrus intortus bio uvrsten u Medjunarodni Atlas Oblaka od strane Svjetske Meteoroloske Organizacije (WMO).

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The new type of cloud forms a dark, lumpy blanket across the sky. The name asperatus translates as roughed,agitated waves or “turbulent undulation”, after the Latin word for rough. This is a low cloud and is seen at about 2000 meters (6000 feet). These clouds are not considered a precursor to severe weather since they don't produce rain or a storm,but rather appear to form following rain or thunderstorm activity. Such clouds are relatively rare, but have been photographed in several areas around the world. The ominous-looking clouds have been particularly common in the Plains states of the United States, often during the morning or midday hours following convective thunderstorm activity. And also over the Arctic Sea just off the coast of Greenland. 

Novi tip oblaka formira taman i ispupcen veo preko neba. Ime asperatus se prevodi kao grubi, uznemireni valovi ili “turbulentna undulacija” po latinskoj rijeci grub. Ovo je niski tip oblaka i moze biti osmotren na visini do 2000m (6000ft). Ovi oblaci se ne smatraju pokazateljem nadolazeceg loseg vremena narocito jer ne proizvode padavine niti oluju, vec se najcesce pojavljuju nakon kise i grmljavine. Prilicno su rijetki ali su ipak fotografisani vise puta sirom svijeta. Oblaci prijeteceg izgleda su relativno cesti na Velikoj ravnici u Americi, najcesce tokom jutranjih ili podnevnih sati nakon konvektivne aktivnosti. Takodjer su vidjeni nadomak obala Grenlanda. 

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The undulating and lumpy underside, however, is thought to be caused by warm and cold air meeting a the boundary between the lower and middle atmosphere creating a transition effect similar to those seen when oil and vinegar mix.There is some disagreement about this though from scientists. It is also believed that Asperatus is a result of warmer, moister air above and colder, drier air below, with an abrupt boundary in between. And add to that wind passing over rolling terrain and there's the imitation of the wavy effect as on the surface of water.

Valoviti i ispupceni dio oblaka prema zemljinoj povrsini se smatra da je prouzrokovan kada se topao i hladan zrak susretnu na granici izmedju niske i srednje atmosfere, kreirajuci prelazni efekat slican onome kada se pomijesaju ulje i sirce. Doduse postoje mnoga neslaganja oko ove tvrdnje. Takodjer se vjeruje da je asperatus oblak rezultat toplijeg, vlaznijeg zraka koji je iznad i hladnijeg, suhog zraka ispod njega sa direktnom granicom izmedju. Na to kada se doda vjetar koji prelazi preko neravne povrsine dobijamo valoviti efekat kao sto je vidjen na povrsini vode. 

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The formation has probably been around for a long time, but it's only
now getting attention.

Ova formacija oblaka vjerovatno je prisutna vec neko vrijeme ali tek sada dobija na paznji.

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:

1. Cirrus – Ci
2. Cirrocumulus – Cc
3. Cirrostratus – Cs
4. Altocumulus -Ac
5. Altostratus -As
6. Nimbostratus -Ns
7. Stratocumulus – Sc
8. Stratus – St
9. Cumulus – Cu
10. 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