Floods in general are not uncommon in South Africa. Recent flooding events do not come near some of the past events, both in strength and the trail of disaster they left behind. South Africa has a long record of flooding events dating back to the 1800s. Sporadic though these records are, they nonetheless give us a glimpse of what happened in the past. This past is very important to anchor our present day discussions, especially in the light of climate change.
The first recorded flood event in KwaZulu-Natal (KZN) was in April 1856, where 686mm of rainfall were reported. It was in September 1987, however that KZN experienced what is considered to be South Africa's greatest natural disaster in terms of lives lost and damage to infrastructure. During this disaster, 506 people lost their lives and approximately 60 000 people were affected one way or another. A few years earlier KZN was devastated by Tropical Cyclone Damoina. On January 1984 Damoina formed in the Indian Ocean to the east of Madagascar. A few days later, it crossed the country and the channel and later made land fall in Mozambique, but drifted southwards to settle near Durban. In its devastating trail, Damoina left about 215 people dead.
Other parts of South Africa have received notable flooding events. One of the documented flooding events in SA happened in the little town of Laingsburg in January 1981. 104 people died when 424mm of rain fell in 2 days. It is reported that over 50 bodies or (between 56 to 72) were never recovered. Those families whose loved one were never recovered later alleged that bodies were buried in mass graves, an allegation that was probed by the democratic western cape. It was found that there was/were no bodies buried in mass graves.
Between January 1911 to December 1988, Viljoen (1990) found that significant flood events manifested themselves as follows:
Cape Peninsula and Boland - 22
South and Eastern Cape coastal areas - 32
KZN - 53
Highveld - 43
Central Interior - 34
There were other floods elsewhere in South Africa, but what has been found is that certain weather systems are responsible for these floods. These weather systems are not freaks of nature. They have been studied in South Africa and good understanding about them exists. In most flood events, it was found that a weather system called, cut-off low was often present. These weather systems were recently studied by Singleton and Reason in their 2007 paper on the climatology of cut-off lows. Theirs was a present day look at these systems, because Taljaard (1990), although using a shorter term data set, about 10 years, studied these systems. Of course cut-off lows have been found to work in concert with other systems, like strong ridging highs, cold fronts, tropical lows to produce significant rainfall amounts.
In South Africa literature about previous extreme weather events, including tornadoes exists. It is intended to bring forth aspects of variability intrinsic in our climate. Any talk of climate change must first take into account what already exists. The next question for me is, the recent floods in almost all provinces, how do they compare to the Natal Floods of 1987? What were the underlying meteorological causes? What lessons have we learned with regards to disaster management efforts?
The first recorded flood event in KwaZulu-Natal (KZN) was in April 1856, where 686mm of rainfall were reported. It was in September 1987, however that KZN experienced what is considered to be South Africa's greatest natural disaster in terms of lives lost and damage to infrastructure. During this disaster, 506 people lost their lives and approximately 60 000 people were affected one way or another. A few years earlier KZN was devastated by Tropical Cyclone Damoina. On January 1984 Damoina formed in the Indian Ocean to the east of Madagascar. A few days later, it crossed the country and the channel and later made land fall in Mozambique, but drifted southwards to settle near Durban. In its devastating trail, Damoina left about 215 people dead.
Other parts of South Africa have received notable flooding events. One of the documented flooding events in SA happened in the little town of Laingsburg in January 1981. 104 people died when 424mm of rain fell in 2 days. It is reported that over 50 bodies or (between 56 to 72) were never recovered. Those families whose loved one were never recovered later alleged that bodies were buried in mass graves, an allegation that was probed by the democratic western cape. It was found that there was/were no bodies buried in mass graves.
Between January 1911 to December 1988, Viljoen (1990) found that significant flood events manifested themselves as follows:
Cape Peninsula and Boland - 22
South and Eastern Cape coastal areas - 32
KZN - 53
Highveld - 43
Central Interior - 34
There were other floods elsewhere in South Africa, but what has been found is that certain weather systems are responsible for these floods. These weather systems are not freaks of nature. They have been studied in South Africa and good understanding about them exists. In most flood events, it was found that a weather system called, cut-off low was often present. These weather systems were recently studied by Singleton and Reason in their 2007 paper on the climatology of cut-off lows. Theirs was a present day look at these systems, because Taljaard (1990), although using a shorter term data set, about 10 years, studied these systems. Of course cut-off lows have been found to work in concert with other systems, like strong ridging highs, cold fronts, tropical lows to produce significant rainfall amounts.
In South Africa literature about previous extreme weather events, including tornadoes exists. It is intended to bring forth aspects of variability intrinsic in our climate. Any talk of climate change must first take into account what already exists. The next question for me is, the recent floods in almost all provinces, how do they compare to the Natal Floods of 1987? What were the underlying meteorological causes? What lessons have we learned with regards to disaster management efforts?
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