Nei Maldaner na Expedição Circunavegação Antárctica 2006 entre novembro e Dezembro de 2006. Cruzando o continente Antárctico, a bordo do quebra gelo Kapitan Khlebnikov. Veja o que ele aprendeu sobre questão dos niveis de Ozone.

The hole in the osone layer



Higher in the atmosphere, UV rays break down oxygen molecules (o2) into free oxygen molecules wich form ozone (o3). Its very important at this altitude as it helps protect us from the sun's harmful ultraviolet rays.

The hole in the ozone layer is a naturally occurring phenomenon and happens every springs in Antartica. By mid-Octuber, the hole slowly recovers as fresh ozone from lower latitudes generally enters the hole.

The hole forms because during the Antarctic winter night, the air is effectively insulted from the rest of the atmosphere by a strong high atmosphere by a strong high pressure system over the south pole. This cold weather allows the form a nucleus for chloriene and bromine molecules in the cold conditions. When the sun returns in spring, the chlorine and bromine molecules heat up and change into molecules whit riochet around the stratosphere, destroying tens of thousands of ozone molecules.

Mans use of CFC's (chlorofluorocarbons) has increased the amount of chlorine in the higher layers if the atmosphere and has accelerated the destruction of Ozone.

Fortunately, every country has signed the Montreal Protocol which has prohibited the use of CFC's in developed countries since 1996, and requieres all countries to cease using CFCs by 2006

In the last couple of years, we have started to see the amount of ozone destoyed level off, but we think it will be about 50m ye3ars before we will see the ozone levels return to closer to natural levels.