Climatic deviations across a transect of South Africa during El Niño and La Niña years

نوع مقاله : مقاله پژوهشی

نویسندگان

School of Geography, Archaeology and Environmental Studies,University of the Witwatersrand, Private Bag 3, Wits, Johannesburg 2050, South Africa

چکیده

South Africa is a water-scarce country that is highly dependent on agriculture. This means that the local impacts of climate altering phenomenon, such as the El Niño-Southern Oscillation (ENSO), are critical to understand. At a broad scale, these systems are known to affect rainfall distribution, resulting in drought (flood) conditions during El Niño (La Niña) events in the majority of the country, and the converse in the southwestern Cape. However, fine resolution analyses of local impacts of these events have been restricted to the coastal zone, and little is known for the interior. We explore the uniformity in the transition of the climatic deviations [for minimum temperature (Tmin) and maximum temperature (Tmax), and rainfall] along a 12-site transect spanning the South African interior. The majority of the deviations determined were not statistically significant which suggests that the common understanding of the climatic impacts of ENSO events in South Africa is not well understood. However, it should be acknowledged that all the locations used in this research, aside from Hermanus, were located inland which may be the reason the deviations at these locations were not statistically significant.

کلیدواژه‌ها


عنوان مقاله [English]

Climatic Deviations Across a Transect of South Africa during El Niño and La Niña Years

نویسندگان [English]

  • Tarisha Harduth
  • Jennifer M Fitchett
School of Geography, Archaeology and Environmental Studies,University of the Witwatersrand, Private Bag 3, Wits, Johannesburg 2050, South Africa
چکیده [English]

South Africa is a water-scarce country that is highly dependent on agriculture. This means that the local impacts of climate altering phenomenon, such as the El Niño-Southern Oscillation (ENSO), are critical to understand. At a broad scale, these systems are known to affect rainfall distribution, resulting in drought (flood) conditions during El Niño (La Niña) events in the majority of the country, and the converse in the southwestern Cape. However, fine resolution analyses of local impacts of these events have been restricted to the coastal zone, and little is known for the interior. We explore the uniformity in the transition of the climatic deviations [for minimum temperature (Tmin) and maximum temperature (Tmax), and rainfall] along a 12-site transect spanning the South African interior. The majority of the deviations determined were not statistically significant which suggests that the common understanding of the climatic impacts of ENSO events in South Africa is not well understood. However, it should be acknowledged that all the locations used in this research, aside from Hermanus, were located inland which may be the reason the deviations at these locations were not statistically significant.

کلیدواژه‌ها [English]

  • El Niño
  • La Niña
  • Temperature
  • Precipitation
  • South Africa
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