sexta-feira, março 17, 2006

Antarctic Ice Sheets Are Growing

O segundo texto, em anexo à carta dirigida ao sr. Provedor de o Público, provinha de um jornal alemão com tradução em inglês. Imagina-se a razão da não publicação deste texto por parte de alguns media. Curiosamente, esta notícia nasce em meios europeus sempre prontos a descobrir os malefícios hipotéticos do «global warming».

Die Welt am Sonntag, 7 March 2005

The West Antarctic peninsula only covers one tenth of the South Pole s ice. There are rarely spectacular reports about the much larger parts of the continent. These do not provide a uniform scientific picture.

In total, however, the ice masses of the continent, which hold about 70 per cent of the world's fresh water resources, seem to be growing. This conclusion was reported at the Earth Observation summit in Brussels in the middle of February by Antarctic researcher Duncan Wingham (University College London).

Wingham presented new satellite data which show that the Antarctic ice cover is getting thicker. "To claim that the ice sheets are melting is rather daring," Wingham said in an interview with Die Welt.

Wingham presented radar measurements taken by the European satellites ERS-2 and Envisat, whose altimeter exactly measures elevations on the earth s surface down to two centimeters by means of electromagnetic wave pulses.

This way, changes of the ice cover can be identified over many years. Soon, even more precise measurements will be possible once the European satellite CryoSat is going to be launched later in June.

Orbiting the Polar Regions, CryoSat will take exact measurements (at the millimeter level) for at least three years of the ice thicknesses on both the mainland and the sea at both poles.

At a conference in Frascati next week, these operations are going to be prepared. However, whether CryoSat's measurements will be able to clarify how the ice cover of the Antarctic (which is up to 4770 meters thick) will evolve in the future, remains questionable.

Systematic climate research has been going on for some 30 years on the seventh continent - with contradictory findings: the climate of the Antarctic is complex. A temperature rise over the western peninsula has coincided with a cooling of the south part of the continent.

And even in the west the ice cover has been growing. Standard explanations claim that a slight warming will lead to intensified snow which freezes. A global temperature rise could possibly lead to the thickening of the Antarctic ice cover altogether. In any case, the doomsday scenario of an Antarctic meltdown and consequently a rise in sea level of up to 60 meters - seems rather unrealistical.