POLAR STRATOSPHERIC CLOUD

Hi guys, in this post I would like to tell you about a natural phenomenon. And the phenomenon is polar stratospheric cloud.

Polar stratospheric clouds or PSCs, also known as nacreous clouds (from nacre, or mother of pearl, due to its iridescence), are clouds in the winter polar stratosphere at altitudes of 15,000–25,000 meters (49,000–82,000 ft). They are best observed during civil twilight when the sun is between 1 and 6 degrees below the horizon. They are implicated in the formation of ozone holes. The effects on ozone depletion arise because they support chemical reactions that produce active chlorine which catalyzes ozone destruction, and also because they remove gaseous nitric acid, perturbing nitrogen and chlorine cycles in a way which increases ozone destruction.

The formation : The stratosphere is very dry; unlike the troposphere, it rarely allows clouds to form. In the extreme cold of the polar winter, however, stratospheric clouds of different types may form, which are classified according to their physical state and chemical composition. Due to their high altitude and the curvature of the surface of the Earth, these clouds will receive sunlight from below the horizon and reflect it to the ground, shining brightly well before dawn or after dusk. PSCs form at very low temperatures, below −78 °C (−108 °F). These temperatures can occur in the lower stratosphere in polar winter. In the Antarctic, temperatures below −88 °C (−126 °F) frequently cause type II PSCs. Such low temperatures are rarer in the Arctic. In the Northern hemisphere, the generation of lee waves by mountains may locally cool the lower stratosphere and lead to the formation of PSCs. Forward-scattering of sunlight within the clouds produces a pearly-white appearance. Particles within the optically thin clouds cause colored Interference fringes by diffraction. The visibility of the colors may be enhanced with a polarising filter.

PSCs are classified into three types Ia, Ib and II according to their chemical composition which can be measured using LIDAR. The technique also determines the height and ambient temperature of the cloud.

Type I clouds contain water, nitric acid and/or sulfuric acid and they are a source of polar ozone depletion.
Type Ia clouds consist of large, aspherical particles, consisting of nitric acid trihydrate (NAT).
Type Ib clouds contain small, spherical particles (non-depolarising), of a liquid supercooled ternary solution (STS) of sulfuric acid, nitric acid and water.
Type Ic clouds consist of metastable water-rich nitric acid in a solid phase.
Type II clouds, which are very rarely observed in the Arctic, consist of water ice only.
Only Type II clouds are necessarily nacreous whereas Type I clouds can be iridescent under certain conditions, just as any other cloud.

Type I

Arctic stratospheric cloud

Type II

Beautiful, isn't it? That's why I chose this phenomenon for this task. Just imagine that above you there is a colorful cloud. Even more if you see it from a very high place. Sounds more like heaven to me. I wish I could see this phenomenon someday :)

(Source : http://en.wikipedia.org/wiki/Polar_stratospheric_cloud
               http://commons.wikimedia.org/wiki/Polar_stratospheric_cloud)

ADVERTISEMENT

On my Tuesday English class yesterday, we had to do advertisement task. It's like we drew an advertisement to advertise something on a hvs paper.
And mine was an advertisement to advertise your advertisement. Lol.

So, if you guys want to publish your advertisement, you can call my agency 'SPACEAIR' via ME and I'll advertise your advertisement. Bang! The cost depends how big is your advertisement and where you want it to be published.
It's not really trusted because it's just a fake advertisement with some creativity by me. But, if you ask me to endorse your things on my instagram i will. And i won't reveal my real number but my instagram is mayalrst if you want teehee.
That's what i did on Tuesday English class, beside causation second test. I wish we can do some creative papers again someday. Thanks for readingg:)

HOLIDAY-YEAY

Holiday yeayy! Finally, after a long semester we got three weeks off! Bye school I won't miss you a second. Fortunately I didn't get any short semester which was a gift from God. Thanks God. So I kept the lesson books off of my eyes, cause I really needed a break after a rough semester. It was my first semester on senior high school but it felt so long and tireeeeeed which was sad.
Well, I spent the most of my holiday in my home. I didn't go to another city nor country because my family is sort of homey type,  but it's okay I could wake up on 10am. Then I surfed the Internet and read some riddles. Riddle's great though, it's like there are a story and it's strange and we have to think what's wrong or who's the murderer yeah some kind of it. It's mind blowing that's why i like them.
On the last Saturday on 2014, I went to Saparua jogging track to 'running'. I woke up early finally. But, actually I just ran the half of the track and ended up walking. Most of them just chit chatting with my bf tee hee. After 'running' we went to ciwalk and decided to watch a movie, it's still 10am so we stopped at J.co and bought j.cool. But guess what, buy two get one free. Alas, we ate three ice cream at once after burned some calories so... The day went so well after all.
So my new year, I got no resolution though, alas. I just hope 2015 goes well. My family didn't celebrate new year,  but we cooked a lot of food because the friends of my grandmother will came and I helped a little on afternoon and went to my room to play some games hehe. I like to be alone at home,I just didn't like people around..  Need some peace in life yo.
On the first Saturday on 2015, I went it with him. We went to bookstore, searched some books. Bookstore is my favorite place to go, I really like to see the stationary and stacked books. I don't mind if I have to go there again and again. Then we went to cafe at Bandung Indah Plaza and then looked up some import books on store named Books and Beyond. Just like every dates,  it went so well.
Well that's my fun part of my holiday, despite of watched dvds and went around some restaurant and cafe with friends. Oh, God the holiday went fast! I'm not ready for the busyness and hectic days of school.... Well I hope this semester goes better than yesterday. Cheer up!