24 Desember 2008

Es Kutub Utara Mencair Lebih Cepat

Washington.
Lapisan es di Kutub Utara terus mencair lebih cepat dari sebelumnya akibat pengaruh pemanasan global. Pantauan lapisan es di Kutub Utara yang dilakukan satelit dalam 30 tahun ini memperlihatkan lapisan es disana mencapai tingkat terendah pada Agustus tahun 2008 ini.

Para peneliti Amerika Serikat dari Pusat Data Nasional Salju dan Es (NSIDC) menyebutkan, pada pengukuran 26 Agustus, luas permukaan es di Kutub Utara menyusut hingga 5,26 juta kolometer persegi, berkurang dibandingkan dengan 21 September 2005 yang seluas 5,32 juta kilometer persegi.

Sejak awal Agustus, menurut Boulder, badan pemantauan Kutub Utara yang berbasis di Colorado, AS, permukaan es disana menyusut sebanyak 0.006 juta kilometer persegi.

Mencairnya es di Kutub Utara, menurut NSIDC, berlangsung sangat cepat dan ekstensif. Ini memungkinkan luas permukaan es akan menyusut hingga dibawah 4,25 juta kilometer persegi. Angka 4,25 juta kilometer persegi, berdasarkan pantauan satelit, merupakan angka terendah luas permukaan es di Kutub Utara, yang tercatat pada musim panas tahun 2007.

Rata-rata luas permukaan es di Kutub Utara, menurut pantauan, selama tahun 1979-2000 adalah 7,23 juta kilometer persegi.

"Intinya adalah tren negatif es pada musim panas memperpanjang berlanjutnya kecenderungan yang telah berlangsung beberapa dekade," demikian tulis NSIDC dalam laporannya.

Glasiologis NSIDC, Mark Serreze memperingatkan, Kutub Utara bahkan bisa tidak berlapiskan es lagi pada bulan September untuk pertama kalinya dalam sejarah modern.

hiii serem banget kaan?

sumber : Kompas.

4 komentar:

elec_mechanical mengatakan...

sepertinya kita memang harus memikirkan masa depan untuk anak cucu kita....

asnur mengatakan...

Baru baca judul postingan yg ini saja sudah mengkhawatirkan rasanya,, Apalagi kalau judulnya "Es Kutub Utara mencair Seluruhnya" ...??

I'm Hernadi-Key mengatakan...

Volcanoes Cool The Tropics, But Global Warming May Have Helped Override Some Recent Eruptions !!!
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Climate researchers have shown that big volcanic eruptions over the past 450 years have temporarily cooled weather in the tropics—but suggest that such effects may have been masked in the 20th century by rising global temperatures. Their paper, which shows that higher latitudes can be even more sensitive to volcanism, appears in the current issue of Nature Geoscience.

Scientists already agree that large eruptions have lowered temperatures at higher latitudes in recent centuries, because volcanic particles reflect sunlight back into space. For instance, 1816, the year following the massive Tambora eruption in Indonesia, became known as "The Year Without a Summer," after low temperatures caused crop failures in northern Europe and eastern North America. More extensive evidence comes in part from tree rings, which tend to grow thinner in years when temperatures go down.

This is one of the first such studies to show how the tropics have responded, said lead author Rosanne D'Arrigo, a scientist at the Tree Ring Lab at Columbia University's Lamont-Doherty Earth Observatory. "This is significant because it gives us more information about how tropical climate responds to forces that alter the effects solar radiation," said D'Arrigo. The other authors were Rob Wilson of Lamont and the University of St. Andrews, Scotland; and Alexander Tudhope of the University of Edinburgh, Scotland.

Along with tree rings, the researchers analyzed ice cores from alpine glaciers, and corals, taken from a wide area of the tropics. When things cool, not only do trees tend to grow less, but isotopes of oxygen in corals and glacial ice may shift. All showed that low-latitude temperatures declined for several years after major tropical eruptions. The samples, spanning 1546 to 1998, were taken from Nepal down through Indonesia and across the Indian and Pacific oceans; the ice cores came from the Peruvian Andes. The researchers used materials they collected themselves, as well as samples from the archives of other scientists.

The data show that the most sustained cooling followed two events: an 1809 eruption that probably took place in the tropics, but whose exact location remains unknown; and the 1815 Tambora eruption, one of the most powerful recorded in human history. Following Tambora, between 1815 and 1818, tropical temperatures dropped as much as 0.84 degrees C (1.5 degrees F) below the mean. A slightly bigger one-year drop came in 1731--0.90 degrees C (1.6 degrees F). The researchers say this may be connected to eruptions at the Canary Islands' Lanzarote volcano, and Ecuador's Sangay around this time.



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byuyyytty_tita mengatakan...

mengerikan, g' bisa bayangin seandainya pencairan itu makin parah. Pulau - pulau di Indonesia tenggelam...
Kita memang harus peduli