Peringatan bersama....

"Wahai anakku, Jauhilah olehmu sifat malas dan banyak mengeluh, kerana sesungguhnya kedua-dua sifat tersebut merupakan kunci dari segala keburukan.

Sesungguhnya jika engkau malas, maka engkau tidak akan mampu melaksanakan kewajibanmu.

Dan jika engkau banyak mengeluh, maka engkau tidak akan sabar dalam melaksanakan kewajibanmu."

(Muhammad bin 'Ali bin al-Husain bin 'Ali bin Abi Thalib)

16 September 2009

10 Rare Cloud Formations

No comments:
Sumber artikel :
<http://listverse.com/2007/10/10/10-rare-cloud-formations/>

This is a list of what I believe to be the top 10 rarest cloud formations. And a brief description of each. No particular order in how ‘rare’ they are though.

1. Nacreous Clouds
These rare clouds, sometimes called mother-of-pearl clouds, are 15 – 25km (9 -16 miles) high in the stratosphere and well above tropospheric clouds. They have iridescent colours but are higher and much rarer than ordinary iridescent clouds. They are seen mostly but not exclusively in polar regions and in winter at high latitudes, Scandinavia, Alaska, Northern Canada. Lower level iridescent clouds can be seen anywhere.
Nacreous clouds shine brightly in high altitude sunlight up to two hours after ground level sunset or before dawn. Their unbelievably bright iridescent colours and slow movement relative to any lower clouds make them an unmistakable and unforgettable sight.

2. Mammatus Clouds
Mammatus are pouch-like cloud structures and a rare example of clouds in sinking air. Sometimes very ominous in appearance, mammatus clouds are harmless and do not mean that a tornado is about to form – a commonly held misconception. In fact, mammatus are usually seen after the worst of a thunderstorm has passed.





3. Altocumulus Castelanus


Also known as jellyfish clouds due to their jellyfish-like appearance. These formed around 17,000 ft due to when the rush of moist air comes from the Gulf Stream and gets trapped between layers of dry air. The top of the cloud rises into a jellyfish shape and long tentacles known as “trailing virga” form from rain drops that have evaporated.




4. Noctilucent Clouds


Noctilucent Clouds or Polar Mesospheric Clouds: This is an extraordinarily rare cloud formation that occurs out on the verge of space between 82km to 102 km from the earth’s surface. Noctilucent clouds appear to be luminous yet they reflect the sunlight from the other side of the earth at night, giving them a glowing appearance






5. Mushroom Clouds
A mushroom cloud is a distinctive mushroom-shaped cloud of smoke, condensed water vapour, or debris resulting from a very large explosion. They are most commonly associated with nuclear explosions, but any sufficiently large blast will produce the same sort of effect. Volcano eruptions and impact events can produce natural mushroom clouds.
Mushroom clouds form as a result of the sudden formation of a large mass of hot low-density gases near the ground creating a Rayleigh-Taylor instability. The mass of gas rises rapidly, resulting in turbulent vortices curling downward around its edges and drawing up a column of additional smoke and debris in the centre to form its “stem”. The mass of gas eventually reaches an altitude where it is no longer less dense than the surrounding air and disperses, the debris drawn upward from the ground scattering and drifting back down (see fallout).
Just paying the bills...


6. Cirrus Kelvin-Helmholtz

Appearing as a slender, horizontal spiral of cloud, cirrus Kelvin-Helmholtz is one of the most distinctive cloud formations. However, it tends to dissipate only a minute or two after forming and, as a result, is rarely observed.
Average height is around 16,500 ft.



7. Lenticular Clouds
Lenticular clouds, technically known as altocumulus standing lenticularis, are stationary lens-shaped clouds that form at high altitudes, normally aligned at right-angles to the wind direction.
Where stable moist air flows over a mountain or a range of mountains, a series of large-scale standing waves may form on the downwind side. Lenticular clouds sometimes form at the crests of these waves. Under certain conditions, long strings of lenticular clouds can form, creating a formation known as a wave cloud.

8. Roll Clouds


A roll cloud is a low, horizontal tube-shaped arcus cloud associated with a thunderstorm gust front, or sometimes a cold front. Roll clouds can also be a sign of possible microburst activity. Cool air sinking air from a storm cloud’s downdraft spreads out across the surface with the leading edge called a gust front. This outflow undercuts warm air being drawn into the storm’s updraft. As the cool air lifts the warm moist air water condenses creating cloud, which often rolls with the different winds above and below (wind shear).

9. Shelf Clouds
A shelf cloud is a low, horizontal wedge-shaped arcus cloud, associated with a thunderstorm gust front (or occasionally with a cold front, even in the absence of thunderstorms). Unlike a roll cloud, a shelf cloud is attached to the base of the parent cloud above it (usually a thunderstorm). Rising cloud motion often can be seen in the leading (outer) part of the shelf cloud, while the underside often appears turbulent, boiling, and wind-torn.

10. Stratocumulus Clouds


According to the Sapporo Meteorological Observatory, these low-altitude stratocumulus clouds were rolled into long, distinctive ribbons after becoming trapped in air currents. While it is not uncommon for wind to form such patterns in stratocumulus clouds, photos that clearly show the clouds rolled into strips are rare, says the observatory.




Contributor: Adam Winkles

13 September 2009

Cabaran-cabaran hidup + general view of geology

1 comment:
Assalamualaikum & salam pembuka bicara..

Antara sedar ataupun tidak, sudah 3 bulan lebih ana berada di perbukitan ilmu UKM ini....
menjalani kehidupan sebagai mahasiswi...dalam bidang Geologi...

Alhamdulillah setakat ini masih berupaya menggagahkan diri untuk 'mantain' di sini, walau kadang-kadang selalu juga tersasar dari landasan

Dalam peringkat permulaan sebegini, bukan senang untuk mencapai kestabilan tahap 'oktet'..
Kata ramai orang;
..hidup di U ini kena pandai imbang akademik & ko-K (atau kegiatan bepersatuan)..


Seperti anak kecil yang belum dapat berjalan dengan sempurna...sekejap dapat bangun, terjatuh balik...
hm..tapi apa yang penting selepas 'terjatuh' itu kita dapat pengajaran yang positif untuk mengatasi masalah yang sama, & hal ini penting untuk membina kekuatan diri dalam menghadapi masalah yang lebih kompleks kelak (..Ya Allah jauhilah kami daripada menghadapi kesulitan dalam hidup & permudahkanlah urusan kami..)

Geologi ni 3 tahun..menurut En. Mohd. Rozi bin Umor (salah seorang pensyarah Sistem Bumi),
SECARA UMUMNYA ada 3 peringkat pembelajaran (mengikut tahun)

1. Tahun Pertama - Peringkat Pengetahuan (Gathering Knowledge)
- pada peringkat ni, pelajar tidak perlu untuk berfikir keras @ memahami secara khusus, cuma perlu hafal..

2. Tahun Kedua - Peringkat Pemahaman
-pada tahap ini pelajar kena berfikir mengapa, bagaimana..proses itu terjadi..etc2

3. Tahun Ketiga - Peringkat Sintesis
-haa..peringkat ni lebih banyak praktikal..kena analisis lebih terperinci...

untuk 1st year geologi ni terbahagi kepada 3 subjek major yang wajib..
>>Sistem Bumi (cerita perihal bumi & hubungkait dengan alam, lebih kepada interaksi & proses pembentukan)
>>Bahan Bumi (lebih mengkhusus kepada batuan, tanah & mineral2.. ha kat sini banyak kena hafal 'spesis' batu & mineral..)
>>Asas Peta (semuanya pasal peta & bentuk muka bumi ~ lebih kepada geografi)

kemudian ada lagi subjek tambahan (yang juga wajib)
>>Fizis Geologi (konsep Fizik yang banyak diambil dari matrikulasi..)
>>Teknik Matematik (belajar balik yang matrikulasi punya)
>>Hubungan Etnik (belajar pasal etnik & kaum, lebih kepada sejarah.. teringat zaman muda2 dulu..eceh..zaman SPM.. sebab itu sejarah tidak boleh dilupakan - kerna jika dilupakan ia akan berulang kembali..kan3)
>>Academic Communication (nama 'glamour' baru untuk English..hehe.. english yang lebih kepada perbincangan akademik..& kena banyak cakapp-nama pun 'komunikasi' kan, ha)

Sekian untuk hari ini :-)
Wassalam