Research shows that eight of the ten strongest droughts in southern Africa since 1900 occurred during the mature phase of El Niño. It has also been noted that El Niño events have led to a severe drought half of the time they occurred. The effect of El Niño on droughts has been exacerbated over the past 50 years.
What is the relationship between El Nino and drought?
During El Niño episodes the normal patterns of tropical precipitation and atmospheric circulation are disrupted, hence triggering extreme climate events around the globe: droughts, floods and affecting the intensity and frequency of hurricanes.
How does El Niño cause drought in South Africa?
Wanders: “The stronger the El Niño signal, the less water is available in the region. … These lower discharges also have a direct influence on water storage levels in the reservoirs. If there is a continuous shortage of water feeding the reservoirs, this will inevitably lead to water shortages and thus drought.
How does El Nino cause drought?
High-pressure systems reduce evaporation and moisture in the atmosphere. El Niño – as the surface temperature of the Pacific Ocean around the central South American coast increases, storm patterns are disrupted. This phenomenon is thought to create droughts in Indonesia and Australia.
How El Nino and La Nina influenced the occurrence of drought in Africa?
El Niño brought below-average rainfall resulting in drought in the south and parts of the central region of the country. … La Niña will likely lead to above-normal rainfall between January and March 2017, increasing the chance of moderate to severe flooding in some river basins in the south and central regions.
What does El Nino cause?
El Nino causes the Pacific jet stream to move south and spread further east. During winter, this leads to wetter conditions than usual in the Southern U.S. and warmer and drier conditions in the North. El Nino also has a strong effect on marine life off the Pacific coast.
What are the impacts of El Niño?
El Niño conditions can cause a wide range of health problems, including disease outbreaks, malnutrition, heat stress, and respiratory diseases. The risk of communicable diseases increases when there is limited access to food, water, and sanitation.
What are the main causes of drought in South Africa?
One of the main causes of drought in South Africa is the variability in rainfall (Mason and Tyson, 2000; Tyson and Preston-Whyte, 2000 and Vogel et al., 2000). The El Niño phenomenon accounts for approximately thirty percent of rainfall variability (Tyson and Preston-Whyte, 2000).
When was the worst drought in South Africa?
South Africa has been experiencing water shortages since 2015, when delayed rainfalls and decreasing dam levels led to a drought. It was the worst drought in the country since 1982. As a result two provinces — KwaZulu-Natal and Free State — were declared disaster areas.
What are 5 causes of drought?
Here are the 5 natural and human causes of drought:
- 1) Land and water temperatures cause drought. …
- 2) Air circulation and weather patterns also cause drought. …
- 3) Soil moisture levels also contribute to drought. …
- 4) Drought can also be a supply and demand of water issue.
Does El Nino bring more rain?
The Short Answer: El Niño is a weather pattern that occurs in the Pacific Ocean. During this time, unusual winds cause warm surface water from the equator to move east, toward Central and South America. El Niño can cause more rain than usual in South and Central America and in the United States.
What are natural causes of drought?
A lack of water in stores such as rivers, lakes, reservoirs and aquifers (water stored underground naturally) can lead to drought. Areas that rely on rainfall and surface water are more likely to experience drought. Surface water quickly evaporates in warm, dry conditions leading to an increased risk of drought.
How does El Nino affect the water cycle?
It is well known that evaporation rates increase as temperature rises. … During El Niño periods, reduced precipitation in these regions leads to lower terrestrial moisture content, so there is less water in the soil available to evaporate.
What are the impacts of El Nino in Africa?
El Nino Impacts (2015/16 Season)
accompanied by high temperatures leading to: – Reduced crop yields – Cattle deaths – Low dam levels due to less inflows – Sectors affected include food security, livelihoods, agriculture, livestock, nutrition, health and water, sanitation and hygiene (WASH).
What are the impacts of El Nino and La Nina?
El Niño and La Niña affect not only ocean temperatures, but also how much it rains on land. Depending on which cycle occurs (and when), this can mean either droughts or flooding. Typically, El Niño and its warm waters are associated with drought, while La Niña is linked to increased flooding.
How does El Nino affect the environment in Africa?
“The consequences of the El Niño phenomenon have resulted in successive droughts and floods affecting many countries, especially those in the Horn of Africa and Southern Africa”, noted the UNOCHA representative. … However, other countries in the region are expected to receive heavy rains which could result in flooding.