Mostrar mensagens com a etiqueta Antártida. Mostrar todas as mensagens
Mostrar mensagens com a etiqueta Antártida. Mostrar todas as mensagens

sexta-feira, 25 de julho de 2008

It's Not Just Another Pretty Sunset...

Rare Cloud Forms Above Antarctica

Last year on July 25, Renae Baker, a scientist with the Australian Bureau of Meteorology, snapped a picture of a rare Nacreous Cloud at the country's Antarctic Mawson station .

The cloud formed at a height of 12.5 miles (20 Km) above the ground and was more than twice as tall as clouds normally seen in Polar Regions.

The Nacreous Clouds — also known as Polar Stratospheric Clouds — form "when the fading light at sunset passes through tiny ice crystals blown along by a strong jet of stratospheric air and they form only in polar latitudes and at extremely cold temperatures."

This type of cloud contributes to the formation of the polar ozone holes and form surfaces where chemical reactions can take place that produce ozone-destroying molecules.

The ice-cold phenomenon also could help scientists understand more about atmospheric conditions and climate change.

According to Andrew Klekociuk, an atmospheric scientist with the Australian Antarctic Division, "These clouds are more than just a curiosity, they reveal extreme conditions in the atmosphere and promote chemical changes that lead to destruction of vital stratospheric ozone."

You can read:
All doc. from
National Geographic
And:
"Antarctica's Atmosphere Warming Dramatically, Study Finds" [March 30, 2006]

quarta-feira, 25 de junho de 2008

The Antarctic winter cannot protect Wilkins Ice Shelf!!!

This is some of the last news given by ESA!
According with ESA - European Space Angency – from 30 May to 31 May 2008, Wilkins Ice Shelf has experienced further break-up with an area of about 160 km² breaking off. This was the the first ever-documented episode to occur in winter, captured by ESA’s Envisat satellite.

Wilkins Ice Shelf, a broad plate of floating ice south of South America on the Antarctic Peninsula, is connected to two islands, Charcot and Latady. In February 2008, an area of about 400 km² broke off from the ice shelf, narrowing the connection down to a 6 km strip; this latest event in May has further reduced the strip to just 2.7 km.” More than half!!!

The ASAR images (…) were acquired as part of ESA’s support to IPY. ESA is helping scientists during IPY to collect an increasing amount of satellite information, particularly to understand recent and current distributions and variations in snow and ice and changes in the global ice sheets.(…)

The Antarctic Peninsula has experienced extraordinary warming in the past 50 years of 2.5°C, (…). In the past 20 years, seven ice shelves along the peninsula have retreated or disintegrated, including the most spectacular break-up of the Larsen B Ice Shelf in 2002.

Everytime I hear or read anything about Antarctic, and all the problems we will have if we don’t stop a bit to think about it, I feel that I can, not to stop it, but to inform you once more about what’s happening around us - it’s never enough to do it!!!
We can’t be so selfish and think that in our generation, we will not have any problem with the environment or global warming… and think that is only a problem of the new generations will come…
No! It’s nothing like that.
We must notice that we are the most responsible of what’s happening now, and before the new generations will come, we also will have to pay ours bills to the environment.
So, let’s to do what we can do… even few… together, we can make a lot. Don’t stop it!!! Think only about what you/we can do to improve it… and be conscious, for your goodness…

Further Information and Animated Photos:
http://www.esa.int/esaCP/SEMG58VG3HF_index_0.html
Thanks to F. Pimentel, who sent me this link.

quarta-feira, 19 de setembro de 2007

Nova Estação Polar na Antártida

A Bélgica está a preparar uma nova Estação de Investigação Científica que será instalada na Antártida durante os meses de Jan-Fev. do próximo ano. A futura base polar, chamada Princesa Elisabeth, tem a forma de uma nave espacial e terá como objectivo melhorar as investigações em áreas como a Microbiologia, Meteorologia ou Fauna, assim como sensibilizar o grande público sobre os efeitos de aquecimento global.

Desta forma, nada melhor que aproveitar a celebração do Ano Polar Internacional 2007-08 que é um Programa Cientifico dedicado às zonas polares do planeta, que decorrerá entre Mar.07 e Mar.09, o qual será divido em duas fases distintas.
O último Ano Polar Internacional decorreu há 50 anos (entre 1957-8).

É importante estarmos atentos, ao que se passa à nossa volta, pois segundo dados revelados pelo National Snow and Ice Data Center da Universidade do Colorado, o degelo do Mar Ártico, durante este mês atingiu o novo record mínimo de 4,42 milhões de quilómetros quadrados, e segundo o “The Guardian”, os cientistas revelaram ainda que no espaço de uma semana desapareceu uma área quase duas vezes maior que a Grã-Bretanha. Nada pouco por sinal!!!








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