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Copenhagen And Climate Change Posted in Climate change, Environment, lingkungan hidup, pemanasan global on Desember 15, 2009| Leave a Comment » The people of the world continue to grapple with the question of how best to combat climate change News November 30, 2009 What Is the Right Number to Combat Climate Change? (http://www.scientificamerican.com/article.cfm?id=right-number-to-combat-climate-change) (https://leonidas1558.files.wordpress.com/2009/12/right-number-to-combat-climate-change_11.jpg)Is there a safe level of carbon dioxide in the atmosphere to prevent “dangerous anthropogenic interference” in the climate? By David Biello Features November 30, 2009 How Can Humanity Avoid or Reverse the Dangers Posed by a Warming Climate? (http://www.scientificamerican.com/article.cfm?id=avoidingdangers-of-climate-change) (https://leonidas1558.files.wordpress.com/2009/12/avoiding-dangers-of-climate-change_1.jpg) With greenhouse gas emissions continuing to rise, strong efforts will be required to reverse global warming See More (http://www.scientificamerican.com/report.cfm?id=copenhagen-and-climate-change)
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Dapatkah Kita Mendaur Ulang Energi Itu Sendiri ? Posted in carbon dioxide, Climate change, energi terbarukan, Environment, lingkungan hidup on November 14, 2009| Leave a Comment »
(https://leonidas1558.files.wordpress.com/2009/11/daur-ulang-energi-300x225.jpg) Untuk menghemat energi dan sumber-sumbernya, dewasa ini kita mendaur ulang hampir segala sesuatu. Dapatkah kita mendaur ulang energi itu sendiri? Jelas sekali, andaikata yang Anda maksudkan dengan daur ulang adalah mengubah sesuatu ke dalam bentuk yang lebih bermanfaat. Kita mengerjakan sepanjang waktu. Pembangkit listrik mengubah air,batu bara, atau energi nuklir menjadi listrik. Dengan pemanggang roti kita mengubah energi listrik menjadi panas. Dalam mesin mobil kita mengubah energi kimia menjadi energi gerak (energi kinetik). Bentuk energi yang berbeda-beda, semua dapat saling dipertukarkan yang kita perlukan hanyalah menemukan mesin yang tepat untuk mengerjakan tugas itu. Baca selengkapnya… (http://www.chem-is-try.org/tanya_pakar/dapatkah-kita-mendaur-ulang-energi-itu-sendiri/) Read Full Post » (https://leonidas1558.wordpress.com/2009/11/14/dapatkah-kita-mendaur-ulang-energi-itu-sendiri/)
Memahami Siklus Karbon Posted in carbon dioxide, Climate change, Environment, karbohidrat, lingkungan hidup on November 4, 2009| Leave a Comment »
(https://leonidas1558.files.wordpress.com/2009/11/map-cycle_interactive_001.jpg) Siklus karbon antara Bumi, atmosfer dan samudra, mempengaruhi iklim kita. Oleh Daniel A. Gorelick – Staf Writer Washington – Karbon: unsur keempat paling berlimpah di alam semesta dan blok bangunan kehidupan di Bumi. Karbon bergerak di seluruh Bumi – antara atmosfer, lautan, batuan sedimen, tanah dan tanaman dan hewan – dalam apa yang disebut para ilmuwan siklus karbon. Memahami bagaimana siklus karbon bekerja sangat penting untuk memprediksi iklim bumi di masa depan. “Untuk memprediksi perilaku sistem iklim bumi di masa depan, kita harus mampu memahami fungsi sistem karbon dan memprediksi evolusi atmosfer karbon dioksida,” tulis ilmuwan Jorge Sarmiento, Steve Wofsy dan kolega mereka dalam laporan tahun 1999 ” sebuah U.S. Carbon Cycle Science Plan. Dalam bentuk murni karbon berujud sebagai berlian atau grafit, bahan dasar pensil. Terikat pada oksigen, hidrogen dan atom karbon lainnya, karbon membentuk senyawa penting: gula dan lemak yang menyediakan energi bagi tanaman dan hewan; minyak bumi, batubara dan gas alam bahwa kekuasaan kegiatan manusia; dan karbon dioksida dan metana, gas atmosfer yang memerangkap panas dari matahari dan menghangatkan Bumi. Tanaman, alga dan beberapa bakteri mengambil karbon dioksida dari atmosfer atau samudra dan mengubahnya menjadi gula (karbon terikat pada karbon lainnya, hidrogen dan atom oksigen), sebuah proses yang disebut fotosintesis. Hewan makan gula, sumber energi, dan menghembuskan karbon dioksida (karbon terikat pada dua atom oksigen) – respirasi. Hewan dan tanaman yang mati dan dikubur di bumi, tetapi senyawa karbon mereka tetap utuh, sumber energi bagi mikroba yang berpesta jasad mereka dan menghasilkan karbon dioksida dan metan (karbon terikat kepada empat atom hidrogen), beberapa di antaranya tetap berada dalam tanah, dan beberapa di antaranya yang lain dilepaskan ke atmosfir. Kadang-kadang, tanaman dan hewan tetap dikubur di dalam tanah atau tenggelam ke dasar laut dan dilindungi dari mikroba. Lebih dari ratusan juta tahun binatang tetap dikompres lebih dalam dan lebih jauh ke dalam bumi. Jaringan dan tulang yang hancur tapi karbon masih tetap ada, setelah membentuk senyawa yang disebut hidrokarbon, rantai panjang atom karbon terikat satu sama lain dan ke atom hidrogen. Hidrokarbon merupakan komponen utama batu bara dan minyak bumi – bahan bakar fosil. Manusia menggunakan bahan bakar fosil untuk menghasilkan panas dan listrik, dan dengan berbuat demikian hidrokarbon dalam bahan bakar fosil diubah menjadi karbon dioksida dan dilepaskan ke atmosfir. Karbon di atmosfer larut ke dalam lautan atau diambil oleh tanaman dan siklus terus berlanjut. Batu di kerak bumi terdiri dari karbon, terbentuk selama jutaan tahun ketika mengikat mineral karbon. Karbon dioksida larut dalam air laut dalam bentuk bikarbonat, yang dikombinasikan dengan kalsium untuk membentuk batu kapur. Pelapukan dan erosi melarutkan senyawa karbon dari batu dalam kerak bumi ke laut. Karbon juga masuk di bawah kerak bumi – sebuah proses yang disebut subduksi – dan gunung berapi, sumber air panas dan geyser memuntahkan karbon dioksida dan metana kembali ke atmosfir. Komponen geologi siklus karbon – pelapukan, erosi, subduksi, pembentukan bahan bakar fosil – terjadi selama jutaan tahun. Komponen biologis dari siklus karbon – fotosintesis, respirasi, dekomposisi oleh mikroba – terjadi selama berhari-hari untuk ribuan tahun. Rata-rata, jumlah karbon yang bergerak melalui komponen biologis setiap tahun adalah 1.000 kali lebih besar daripada jumlah karbon yang bergerak melalui komponen geologi setiap tahun. ANGGARAN GLOBAL CARBON Masalahnya sekarang adalah bahwa siklus karbon adalah garis miring. Butuh ratusan juta tahun untuk mengendapkan karbon jauh di dalam bumi dan di bawah dasar laut, dan manusia telah melepas banyak karbon ke atmosfir selama abad terakhir. Christine Goodale, ekologi hutan di Cornell University di negara bagian New York, mengkarakteristikannya sebagai “mengambil karbon yang terkunci dan memasukkannya ke dalam bentuk yang jauh lebih aktif di atmosfer.” Manusia juga menghancurkan hutan, melepaskan lebih banyak karbon dioksida ke atmosfer dan mengurangi jumlah tanaman yang menyerapnya dari atmosfer. Atmosfir dipenuhi dengan karbon, terutama karbon dioksida (CO2). Sebagian diserap oleh lautan, sebagian diserap oleh tanaman dan tanah, meski bagaimana terjadinya hal ini tidak dipahami dengan baik. Karbon yang tetap berada di atmosfer menyerap panas, mencegahnya memancar keluar ke ruang angkasa. Tanpa panas yang terjebak ini bumi tidak akan didiami. Terlalu banyak panas, dan iklim akan berubah dan menjadi kurang penghuni. Hal yang sama berlaku untuk lautan, di mana peningkatan karbon akan merubah kimiawi air laut, membuat lautan kurang layak huni dan membunuh kehidupan laut. Karbon di atmosfer bisa baik dan bisa buruk, seperti halnya air: manusia membutuhkannya untuk bertahan hidup, tapi terlalu banyak dan Anda akan tenggelam. Menurut laporan 2007 oleh Panel Antar Perserikatan Bangsa-Bangsa pemerintah tentang Perubahan Iklim (the United Nations Intergovernmental Panel on Climate Change), “sekitar 50 persen dari peningkatan karbon dioksida akan dihapus dari atmosfer dalam waktu 30 tahun, dan selanjutnya 30 persen akan dihapus dalam beberapa abad. Sisanya 20 persen dapat tinggal di atmosfer selama ribuan tahun. ” Bumi dan atmosfer adalah sistem tertutup, di mana karbon tidak diciptakan atau dihancurkan. Jumlah total karbon tidak berubah – karbon dapat berjalan dari kolam ke kolam renang, dari atmosfer ke laut, dari tanah ke endapan, tetapi tidak dapat ditambahkan atau dihapus. Karbon di atmosfer, misalnya, tidak bisa dilepas dalam angkasa luar. Ia harus pergi ke suatu tempat di Bumi: diambil oleh tanaman, atau dilarutkan kembali ke lautan. Naskah aslinya: (http://www.america.gov/st/energy-english/2009/June/20090604124428adkcilerog0.9673578.html?CP.rss=true # ixzz0VtzRzFcN) Read Full Post » (https://leonidas1558.wordpress.com/2009/11/04/memahami-siklus-karbon/)
Invention Captures Carbon Dioxide Emissions Posted in carbon dioxide, energi terbarukan, green energy, hemat energi, lingkungan hidup, news, teknologi on Oktober 19, 2009| Leave a Comment »
(https://leonidas1558.files.wordpress.com/2009/10/20090916182340-1.jpg) Submitted by LiveScience Staff (http://www.livescience.com/environment/etc/090921-invention-captures-carbon-dioxide-emissions.html) posted: 21 September 2009 11:14 am ET Researchers have shown the benefits of a new approach toward eliminating carbon-dioxide emissions at coal-burning power plants. The system, called pressurized oxy-fuel combustion, separates the carbon-dioxide emissions produced by the burning of coal, in the form of a concentrated, pressurized liquid stream, from other emissions. This allows for carbon dioxide sequestration. That means, in theory, the liquid CO2 stream could be injected into geological formations deep enough to prevent their escape into the atmosphere, a process other researchers say could work as a way to store the carbon for eons, thereby keeping it out of the atmosphere. A paper describing the research, led by Ahmed Ghoniem at MIT, was published in August in the journal Energy. The Italian energy company ENEL, the sponsor of the research, plans to build a pilot plant in Italy using the technology in the next few years. (Read full story at MIT (http://web.mit.edu/newsoffice/2009/oxyfuel-coal.html) ) Read Full Post » (https://leonidas1558.wordpress.com/2009/10/19/invention-captures-carbon-dioxide-emissions/)
Build it Green Posted in carbon dioxide, energi, energi alternatif, energi terbarukan, green energy, hemat energi, lingkungan hidup on Oktober 19, 2009| Leave a Comment »
(https://leonidas1558.files.wordpress.com/2009/10/top10_green_trees.jpg) Trees, in a word, rock. They absorb heat-trapping carbon dioxide, hold soil together to prevent landslides, and provide a rich habitat for diverse plants and animals. Choose furniture made from eco-friendly sources such as sustainably managed forests, bamboo, and reclaimed wood. Buying vintage wherever possible, rather than adding something new into the waste stream, is always in style. Also, look for furniture that is durable and likely long-lived-you’ll save money on replacements in the future and prevent more wasted materials from winding up in the landfill. And, if for some reason, that dresser or dining table no longer suits your needs, something in fine shape will always have takers via Craig’s List, eBay, or Freecycle. (Read full story) (http://www.livescience.com/environment/top10_ways_green_home-1.html) Read Full Post » (https://leonidas1558.wordpress.com/2009/10/19/build-it-green/)
Methane Hydrate Posted in energi alternatif, energi terbarukan, lingkungan hidup, news, teknologi on November 25, 2008| 1 Comment »
China and India Exploit Icy Energy Reserves By Gerald Traufetter China and India have reported massive finds of frozen methane gas off their coasts, which they hope will satisfy their energy needs. But environmentalists fear that tapping these resources could have adverse effects on the world climate.
(https://leonidas1558.files.wordpress.com/2008/11/01020104602700.jpg)On the surface, it looked like any other drill core from the ocean floor. Its shimmering grayish-green surface was both slippery and grainy at the same time. But the sample only revealed its exciting secret when the geologists on board the “Bavenit,” a drilling ship, lowered the pressure in the steel tube and held a lit match to the upper end. Suddenly a yellowish-red flame began licking from the slick material. “As astonishing phenomenon,” noted the scientists from the Guangzhou Marine Geological Survey. So astonishing, in fact, that when their ship pulled into the harbor at Shenzen on June 12 of this year, the scientists were all smiles. Shengxiong Yang and Nengyou Wu, the two expedition leaders, stand an excellent chance of going down in the history of their country as heroes. The material they pulled from the muddy ocean floor of the South China Sea has the potential to satisfy the energy needs of China and its fast-growing economy. The flames in the drill core were coming from methane hydrate, a material first discovered in the 1970s. Its unique characteristic is that it is a seemingly frozen and yet flammable material. In the West, this potential fuel from the ocean floor has for the most part been the stuff of fantasy. But it’s a different story in Asia. The People’s Republic of China is investing millions to study this massive source of energy. The same holds true for India, South Korea and Taiwan, all nations that are on a fast track to surpassing the West as economic powers.
FROM THE MAGAZINE Find out how you can reprint this DER SPIEGEL article in your publication. (http://www.spiegel.de/international/0,1518,460322,00.html) These countries — especially China, which produces one third of the world’s steel and aluminum and half of its cement — are playing a key role at the United Nations Climate Change Conference, currently being attended by roughly 10,000 delegates on the Indonesian island of Bali. The needs of these emerging economies continue to rise. Each year, China increases its power consumption by an amount equal to France’s total annual power production. By the end of 2007, the country, with its population of 1.3 billion, will have surpassed the United States as the world’s No. 1 producer of greenhouse gases. It is one of the ironies of the Kyoto Protocol that China is still treated as a developing country, which means that, legally speaking at least, it is not obligated to pay any heed to climate protection issues. However, China and the world’s other budding economic superpowers will no longer enjoy that status under a follow-up agreement to Kyoto, which the delegates in Bali plan to initiate. The Chinese government is pursuing a double strategy. On the one hand, it expresses great concern over climate change. Observers were astonished to note that Prime Minister Wen Jiabao used the terms “environment,” “pollution” and “environmental protection” 48 times in his address to the National People’s Congress this year. China, he said, will not repeat the mistake of “polluting first and cleaning up later.”
At the same time, however, China is energetically seeking new ways to satisfy its voracious demand for more energy. And Chinese officials are pinning their hopes on methane hydrate as one of these ways. Graphic: Energy from Ice
(http://www.spiegel.de/international/world/0,1518,grossbild-1046027-523178,00.html) Graphic: Energy from Ice Methane, trapped in an icy cage of water molecules, occurs in permafrost and, in even greater quantities, beneath the ocean floor. It forms only under specific pressure and temperature conditions. These conditions are especially prevalent in the ocean along the continental shelves, as well as in the deeper waters of semi-enclosed seas (see graphic). World reserves of the frozen gas are enormous. Geologists estimate that significantly more hydrocarbons are bound in the form of methane hydrate than in all known reserves of coal, natural gas and oil combined. “There is simply so much of it that it cannot be ignored,” says leading expert Gerhard Bohrman of the Research Center for Ocean Margins (RCOM) in the northern German city of Bremen. A few months ago, Chinese Premier Wen Jiabao held the material in his hand — or rather, in a metal ice bucket with flames shooting from the top. He was visiting an Australian research center at the time, but now he can just as easily watch the same spectacle unfold in Chinese research laboratories. The Chinese researchers found the methane hydrate, also known as crystal gas, because of its molecular structure, in a layer of sediment 15 to 20 meters (50 to 65 feet) thick off the Chinese coast. “It was embedded in clay and silt ,” says John Roberts, whose firm Geotek provided the technical equipment for the drilling expedition. This is the sort of information natural gas companies like to hear. The porosity of this sediment mix is well suited to drilling for the gas. “The gas hydrate has never found in this form before,” Roberts explains. It suddenly seems conceivable that production using conventional techniques could work. One possible method would involve the use of drilling tubes that would conduct heated fluid into the cold reservoirs. This would dissolve the icy cage encasing the methane. The next step would be to capture the gas through a second opening. These are the kinds of prospects that have inspired others to emulate the Chinese researchers’ success. Japan has built the world’s largest research drilling ship, the Chikyu, primarily to study methane hydrate. India has invested €200 million to launch a major national program — and has already reported successes. Read Full Post » (https://leonidas1558.wordpress.com/2008/11/25/methane-hydrate-2/)
Methane Hydrate Posted in energi alternatif, energi terbarukan, lingkungan hidup, teknologi on November 25, 2008| Leave a Comment » SECONDARY Article: Energy on Ice – Methane Hydrates What are the energy sources of the future? Some scientists believe methane hydrate is one of the answers. But what, exactly, is it? A gas hydrate, such as methane hydrate, is a crystalline solid known as a clathrate. The word clathrate has its origins in the Latin word meaning “to enclose with bars.” It follows then that clathrates are a class of chemical substances made of two unique materials, one of which encloses the other in an open, lattice-like cage. There is no chemical bonding to hold the two materials together, only the physical structure. The most abundant naturally forming clathrate is methane hydrate. Methane hydrate is formed when water molecules freeze around a molecule of methane gas. It is typically found in two distinct geologic areas—on land in the subsurface sediments of permafrost regions, or in oceanic sediments under at least 450 meters of water. Pressure, temperature, and the availability of water and methane are the determining factors in how much hydrate develops. When hydrates form they fill in the porous space in the sediments. As early as 1890, scientists were studying clathrates. At that time they were considered a laboratory oddity, mostly because they often formed well above the freezing point of water. It wasn’t until 1930, when natural gas pipelines were extended into colder climates, that methane hydrates received more attention. Engineers discovered that water ice was not a problem for pipeline flow in the colder regions, the real culprit was methane hydrate. Even with this discovery, the clathrates were considered a nuisance rather than a resource. In 1964, the attitude of laboratory oddity or engineering nuisance changed to one of potential energy resource when a Russian drilling crew in northern Siberia encountered naturally occurring methane hydrate. This frozen natural gas discovery started a worldwide search for more deposits. By the 1970s, methane hydrate had also been located in ocean sediments. Most methane hydrate deposits in the U.S. are located in the Alaskan Outer Continental Shelf. Additional deposits are onshore in northern Alaska, in the Gulf of Mexico, and on the western and eastern outer continental shelves. The U.S. Geological Survey (USGS) estimates the U.S. to have about 200,000 trillion cubic feet of methane hydrate. This number dwarfs the estimated 1,400 trillion cubic feet of recoverable conventional methane from natural gas reserves and reservoirs. Worldwide estimates of methane hydrate deposits reach the overwhelming number of 400 million trillion cubic feet—far outdistancing the 5,500 trillion cubic feet of proven worldwide gas reserves. The U.S. relies on natural gas for heating, cooking, transportation, industry and products. As national and worldwide supplies become more scarce, new resources for methane are a domestic priority. According to the U.S. Department of Energy, Office of Fossil Energy, “If only one percent of the methane hydrate resource could be made technically and economically recoverable, the United States could more than double its domestic natural gas resource base.” To that end, Congress approved the Methane Hydrate Research and Development Program in 2000. This program has provided tens of millions of dollars in matching seed funds for research and development of methane hydrate as an energy resource. More recently, in November 2005, the U.S. Department of Energy announced $2 million in funding for five research projects focused on the energy potential, safety and environmental impacts of methane hydrate exploration and development. Scientists are researching specific concerns about methane hydrate recovery and use which include drilling safety issues, potential influences on global climate change as methane is a potent greenhouse gas and the natural release of vast quantities from hydrate deposits would affect the global carbon cycle, cost effective transportation of the gas to the surface, and the possible impact of hydrate removal on ocean floor stability. As natural gas supplies decrease and the demand for cleaner fuels increases, methane hydrates may well play a role in the U.S. energy portfolio. For more information about methane hydrates, visit: 1. U.S. Department of Energy Office of Fossil Energy: www.fe.doe.gov/programs/oilgas/hydrates (www.fe.doe.gov/programs/oilgas/hydrates) 2. U.S. Department of Energy National Energy Technology Laboratory: www.netl.doe.gov/scngo/NaturalGas/hydrates/rd-program/GOM_JIP/index.html (www.netl.doe.gov/scngo/NaturalGas/hydrates/rd-program/GOM_JIP/index.html) 3. U.S. Department of Interior U.S. Geological Survey: http://woodshole.er.usgs.gov/project-pages/hydrates (http://woodshole.er.usgs.gov/project-pages/hydrates) Read Full Post » (https://leonidas1558.wordpress.com/2008/11/25/methane-hydrate/)
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