Drought is here to stay
2005-01-18 08:00
Elise Tempelhoff
Johannesburg - Hydrologists and agriculturists must start looking into drought-resistant crops because climate changes will result in the country getting less rain in future.
"South Africans should not be blinded by recent good rains," said Francois Engelbrecht, lecturer in the department of geography, geo-informatics and meteorology at the University of Pretoria.
Research has shown that the effects of climate changes are already manifesting in South Africa's weather patterns.
"It is time we admit that global warming is a reality."
Engelbrecht said on Monday greenhouse gasses were going to have a devastating effect on Southern Africa.
"The eastern and central parts of the country, including Limpopo, North West, Gauteng and Mpumalanga, are already becoming drier.
"Ironically, the Northern Cape interior has become wetter over the past 50 years."
He said a high-pressure system had already formed over the largest part of Southern Africa, and this was increasing in intensity.
The system was being fed by air that had been warmed by greenhouse gasses over the equator.
"The warm air rises into the air about 15 km above the equator and cannot escape into the atmosphere. It is forced into a northerly or southerly direction. The air that is forced southward, moves towards the west because of the earth's rotation and then gathers to form a massive subtropical high-pressure system over the central parts of South Africa.
"This system has become stronger because of the massive inflow of air from the equator. This is the key to climate change.
"The high pressure system forces the cold fronts to the south, preventing them from reaching the Western Cape. This is why the Cape is getting less rain," Engelbrecht said.
Prof Dieter Holm, secretary of the international solar energy association and president of the South African association for sustainable energy, believed South Africa's contribution per capita to climate change and global warming should not be underestimated.
While countries in the European Union which signed the Kioto Protocol were doing much to reduce their industrial emissions, South Africa has achieved "very little" in this regard. "But there is a lot we can do," Holm said.
- Die Burger