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Archive for Januari, 2006

Meskipun (menurut perasaan) temperatur di sekitar kita terlihat berfluktuasi secara tetap, namun pada kenyataannya (berdasarkan data yang ada) ternyata selama 50 tahun terakhir ini temperatur rata-rata di Bumi telah naik secara cepat. Penyebab utama naiknya temperatur Bumi adalah akibat efek rumah kaca yang menurut sebagian ahli disebabkan oleh meningkatnya kandungan gas Karbon Dioksida (CO2) dan partikel polutan lainnya di atmosfer Bumi. Diibaratkan selimut, gas-gas tersebut akan menghalangi energi panas yang dipantulkan kembali oleh Bumi ke ruang angkasa.

Untuk membayangkan efek rumah kaca ini sangat mudah. Mungkin ada di antara anda yang sudah pernah merasakan bagaimana ketika pertama kali memasuki sebuah mobil yang diparkir di tempat yang panas. Temperatur di dalam mobil akan terasa lebih panas daripada temperatur di luar, karena energi panas yang masuk ke dalam mobil terperangkap di dalamnya dan tidak bisa keluar.

Pada kondisi yang normal, efek rumah kaca adalah “baik” karena dengan demikian Bumi akan menjadi hangat dan dapat menjadi tempat hidup manusia dan makhluk hidup lainnya. Tanpa efek rumah kaca, bagian Bumi yang tidak terkena sinar matahari akan menjadi sangat dingin seperti di dalam freezer lemari es anda (-18C). Sejarah terbentuknya Bumi hingga bisa ditempati oleh manusia seperti saat ini sebenarnya tak lepas dari ‘jasa’ efek rumah kaca. Jadi sebenarnya yang namanya efek rumah kaca itu sudah ada sejak jaman dahulu kala seiring dengan proses terbentuknya Bumi.

Kondisi akan menjadi tidak baik jika kandungan gas-gas rumah kaca di atmosfer Bumi semakin hari semakin meningkat. Kenapa demikian? karena dengan semakin meningkatnya gas-gas rumah kaca, semakin memanas pula Bumi, akibatnya akan terjadi pencairan es di daerah kutub yang dapat menenggelamkan sebagian daratan tempat manusia dan makhluk-makhluk hidup darat lainnya tinggal.

Gas rumah kaca yang saat ini banyak disalahkan oleh sebagian ahli pengusung isu pemanasan global adalah gas CO2 di atmosfer. Sementara sebagian ahli lain berpendapat bahwa sebenarnya jumlah CO2 di atmosfer tidak cukup signifikan untuk dijadikan “kambing hitam” pemanasan global karena jumlahnya yang hanya 0.04%. Selain itu, para ahli ini juga menyatakan bahwa seluruh gas yang ada di atmosfer adalah gas rumah kaca, tanpa terkecuali dimana komposisi terbesar adalah nitrogen (78%), oksigen (21%) dan uap air (hingga 3%). Nah lo, pusing kan jadinya? Santai, tidak perlu pusing…

Lalu, apakah yang menyebabkan meningkatnya kandungan karbon dioksida dan partikel polutan di atmosfer? Ternyata kontribusi terbesar adalah akibat pemakaian bahan bakar fosil seperti batubara, gas dan minyak Bumi. Ketiga jenis bahan bakar tersebut adalah yang paling murah saat ini jika dibandingkan dengan sumber energi lainnya. Pemakaiannya pun dari tahun ke tahun terus mengalami peningkatan yang sangat berarti setelah tercetusnya revolusi industri. Apalagi kalau sekarang kita sering merasakan kemacetan di mana-mana akibat jumlah kendaraan bermotor dan “bermobil” yang meningkat. Pabrik/industri yang tumbuh di mana-mana untuk memenuhi pola konsumsi masyarakat modern yang semakin hari semakin meningkat. Namun hal ini juga disangkal oleh sebagian ahli. Menurut mereka, kontribusi dari penggunaan bahan bakar fosil di seluruh dunia dalam menambah jumlah CO2 hanyalah 0,013% (sedikit sekali bukan?). Wah jadi makin seru deh sampai di sini…

Pro dan kontra terus terjadi, namun demikian seiring dengan adanya Protokol Kyoto (1997), Beberapa negara maju sepakat untuk mengurangi jumlah emisi gas CO2 dengan mengurangi pemakaian bahan bakar fosil sebanyak 30% dalam 10 tahun ke depan. Untuk itu saat ini beberapa negara maju/industri telah mencoba mengembangkan metode dan teknologi dalam rangka memanfaatkan sumber-sumber energi alternatif yang (lebih) ramah lingkungan, terutama sumber energi yang terbarukan.

Apa itu energi terbarukan? Energi terbarukan adalah lawan kata dari energi tak terbarukan (anak kecil juga tahu kalau gitu sih). Jadi begini, energi terbarukan adalah energi yang dapat dipakai secara terus- menerus tanpa perlu kuatir sumber dari energi tersebut akan habis. Lawan katanya adalah energi tak terbarukan yaitu energi yang jika dipakai secara terus-menerus akan habis pada suatu waktu tertentu. Jadi jelas kan sekarang? Apa saja contoh dari energi terbarukan? banyak sekali, seperti energi angin, matahari, panas bumi, air, dan biomassa (berasal dari tanaman perkebunan, pertanian, hutan, sampah, dan peternakan).

Sebenarnya, secara alamiah di alam, akibat adanya interaksi antara laut dan udara (seperti TNI aja ya?), jumlah energi panas yang ada di atmosfer dan di permukaan laut akan dapat dikontrol oleh mekanisme global conveyor belt. Apa itu global conveyor belt? Global conveyor belt adalah sirkulasi global yang berperan dalam mentransfer (memindahkan) energi panas dari suatu tempat ke tempat lainnya melalui aliran udara dan air laut. Pola iklim di bumi diatur oleh mekanisme ini.

Satu hal yang perlu diingat adalah bahwa ‘ketakutan’ dan analisis sebagian ahli akan pemanasan global selama ini masih baru didasarkan melulu pada hasil model numerik yang belum secara ‘sungguh-sungguh’ dibandingkan dengan data pengamatan. Selain itu, kebanyakan model yang digunakan saat ini masih jauh dari sempurna dalam merumuskan mekanisme rumit sesungguhnya yang terjadi di Bumi.

Memang pemanasan global sedang dan terus akan terjadi, demikian juga dengan efek rumah kaca. Mencairnya es yang terbentuk sejak jaman es pun terus berlangsung karena memang temperatur bumi mengalami perubahan dari semenjak es itu dahulu terbentuk, permukaan laut pun terus mengalami kenaikan (yang dikenal dengan istilah sea level rise). Siklus seperti itu terus terjadi dan takkan terhindarkan. Sebagian pakar menyatakan bahwa fenomena itu masih merupakan suatu kewajaran yang memang harus terjadi dan tak perlu ditakutkan, sementara itu pakar yang lain -seperti yang telah saya tuliskan di atas- menyatakan bahwa dalam kurun waktu 50 tahun terakhir ini “kecepatan” dari fenomena ini meningkat dan berada pada level yang “sangat mengkhawatirkan”, artinya jika “masa mengkhawatirkan” ini tidak segera diredam, maka ke depannya peradaban manusia akan mengalami masalah yang serius.

Jadi memang tak ada salahnya untuk membuat suatu aksi yang positif. Setidaknya, dengan mengurangi emisi CO2 dan mengurangi pemakaian bahan bakar fosil serta mencoba alternatif energi ramah lingkungan dan terbarukan, akan menjadikan Bumi sedikit bersih dari polutan yang telah membuat manusia sesak nafas dan teracuni paru-parunya. Apalagi untuk Indonesia yang saat ini berada pada tingkat polusi yang katanya sudah agak membahayakan bagi kesehatan penduduknya.

*disarikan dari berbagai sumber*

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Clever and Smart

Some of my friends said that Indonesia has a lot of “clever” people but, unfortunately, not “smart” enough. This statement appears when we have some discussion about a lot of “never ending” problems in our country that accumulated by time and make some “normal” people get frustration.

Well, maybe this statement is so sarcastic for some of us, but my friends said this is our reality. We have no ability to manage the problems and -more than that- we have no ability to control our ego for better Indonesia. This is one of the clearest sign that we are not “smart” enough! The “smart” always thinks and solves something based on the good strategy, manage the problem in best way, and has a sustain solution, not just an instant one, they said.

Honestly, this is a hard discussion for me and so far I just keep my self as good listener. But, I think they are right with their “sarcastic” statement, eventhough I am not sure yet that they -who have this “sarcastic” statement- are realy “smart” people or just can talk about it in discussion but have no idea how to implement in the real world -unless they can proof it to Indonesia people or at least to me as their good listener-.

The tongue has no bone, talks easier than acts! (is the English translation correct?)

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I have decided to make my other blog “oseanografi” (in Indonesia languange) has an “up to date” and good content in oceanography from many aspects. So far, I just write articles in this blog based on the the text books or my experiences.

Now, living in Hamburg, I can access almost on-line international journals in oceanography for FREE because the Institute where I work for my PhD. subscribes to those online journals . I always try to read one paper everyday to get “up to date” information about oceanography. I think it will more useful for others if I can make article about what I’ve read and publish it in my oceanography blog (of course I will not just translate the paper to Indonesia language because of copyright issue).

So far, based on my experience, it is quite diffficult to get new scientific papers about oceanography in Indonesia library. Sometime, when I was in Indonesia, I have to contact my friends in Japan or somewhere else in developed countries to help me downloading the papers that I need and send them by e-mail. Of course, based on the policy from the publisher, this kind of “friend to friend order” is not allowed, but how can poor student like my self order the papers for $9.0/paper? In some cases, if the writers still have the copy, I can contact them and ask for the copy or digital form of their papers.

Well, I think, “famous” universities in Indonesia -such as ITB, UI, etc.- should think about give “up to date” on-line journal facility to their researchers, lectures staff, and students. On the other hand, students who have paid much money for their study should ask for it also to their university. Logically, how can they paid much money but got scientific facility in “minimalist” style, while their teachers also sometime very busy with their “private” projects and neglected their main job as teacher (honestly, I don’t like this kind teachers!).

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Expert status, what for?

I just discussed about the term “expert” with my wive. This discussion appears after we read a polemic about “expert” in a mailing list (milis) subscribed by her. One of the milis member, a Proffesor, said that in Indonesia a lot of people claim their selves as “experts”, but honestly they are not realy “experts”. Just claim their selves as experts, but actually do nothing and have no good scientific “international” publications. He argues that one factor to become “experts”, scientists or researchers should have international publications, not just become a member of “international” or “regional” organisations.

Partly, (maybe) I agree with him but well I have also another opinion. Perhaps, have international publications are very important, and maybe can also indicating the quality, for scientists or researcher. But, how can we have good publications if do nothing or just doing “commercial” project and “instant” order from private companies or consultants?

Some of my friends said that now Bandung is very very dirty, garbage are everywhere. Moreover a friend teased that not only human got trouble with the waste, the flies also got headache and tired. As you know, in Bandung there is a famous Instititute of Technology named ITB. ITB has Departement of Environmental Technology with (I think) a lot of Doctors and Proffesors there, and I am realy sure they know very well about waste management and processing. I am also realy sure, they have a lot of publications in national and international scopes. The question is “how can the city that has a famous institute of technology with a lot of experts in environmental technology has a waste management and processing problem?”

Well, actually I still have no answer regarding to this question. But with this illustration I just want say that just claimed our selves as experts or relied on publications are not enough, we need more than that: responsibility, action and commitment.

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Angie’s blog

I just read Angelina Sondakh’s blog. She is a parliament member from Democratic Party and also Miss Indonesia 2001. She wrote that now she is falling in love with Adji Massaid, an actor who also a parliament member from Democratic Party.

Oh ya, in her blog you can also read a posting with title: “Comment from Republic Indonesia First Lady Ibu Hj. Ani SBY about Agelina Sondakh.” Hehehe… little bit funny, and I think this is typical Indonesia, especially when you read that “welcome message” comment in detail : so formal.

Anyway, I give appreciation to her effort launching a blog and hoping so much that the articles in her blog are not just telling about her love story (with Adji), but more than that she can talk much about her visions as a parliament member.

I’ll wait for your next post Angie!

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Sudoku

I just tried to play Sudoku, a logic-based placement puzzle game. The name Sudoku is the Japanese abbreviation of a longer phrase, “suji wa dokushin ni kagiru,” meaning “the digits must remain single”; it is a trademark of puzzle publisher Nikoli Co. Ltd in Japan (source: Wikipedia).

Well, I think it is quite difficult to play this game (so far, especially for a beginner like my self), but I realy enjoy this game (eventhough I need very long time to finish 9×9 grids).

Oh ya, for the rules of playing Sudoku, Wikipedia has a complete entry of it. The rules are quite easy, and I think, you can directly playing this game after finish reading the entry. The aim of this game is to enter a numerical digit from 1 through 9 in each cell of a 9×9 grid made up of 3×3 subgrids (called “regions”), starting with various digits given in some cells (the “givens”). Each row, column, and region must contain only one instance of each numeral.

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When in college, I was so difficult to explain about Coriolis force in detail and clear to friends. The main problem is because this force is a virtual force, works in large scale, and we can’t feel it. This force appears because of the earth rotation.

Some teachers around the world, sometime give bad explanation also when talk about the Coriolis force. One of popular bad example is when teachers said: “The water in a sink (or toilet) rotates one way as it drains in the northern hemisphere and the other way in the southern hemisphere. Called the Coriolis Effect, it is caused by the rotation of the Earth.”

As I mentioned above, the Coriolis force appears as an effect of earth rotation, while the earth rotation is very slow, only one rotation per day. On the other hand, the water in a sink might make a rotation in a few seconds and so have a rotation rate ten thousand times higher than that of the Earth. It should not be surprising, therefore, to learn that the Coriolis force is orders of magnitude smaller than any of the forces involved in these everyday spinning things. The Coriolis force is so small, that it plays no role in determining the direction of rotation of a draining sink anymore. Actually, the direction of rotation of a draining sink is determined by the way it was filled, or by vortices introduced while washing. So, have no relationship with Coriolis force and of course earth rotation.

I found one good and clear description about Coriolis force at the book I am reading now: The Oceans by Ellen J. Prager (FYI: I never finish read this book, because I only read this book when in train or bus).

In this book she ilustrated the Coriolis force by writing a funny story about a war on drugs where a US soldier has to fire a missile from Washington DC to Columbia. The missile is launched, however it lands not in Columbia but on one of small islands in the Galapagos Archipelago, 500 miles west of South America. Numerous endangered tortoises and much of their fragile habitat are annihilated, environmental groups vigorously protest at the White House and Ecuadorian officials are enraged. The US takes quick action to fire the soldier. Much to his chagrin and embarrassment, the soldier realizes his mistake: he forgot to program the missile guidance system to adjust for the Coriolis effect.

After that, the story continued by explaining in detail the Coriolis force. Better you buy the book or, may be, you can borrow it from me after I finish read it, but I am not sure when I’ll finish read this book. You know, I am a lazy man! 🙂

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