The diurnal cycle of rainfall in South Africa in the austral summer

Mathieu Rouault, Shouraseni Sen Roy, Robert Balling

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

The diurnal cycle of precipitation over South Africa during summer is analysed for the first time using hourly precipitation data from 103 stations for the period 1998-2007. Using harmonic analysis, we found the presence of a distinct diurnal cycle over most of South Africa regarding both the frequency and amount of precipitation events. The standardized amplitudes, indicative of the strength of the diurnal cycle across a region, are strongest over the interior and along the east coast of South Africa with up to 70% explained variance associated with the diurnal cycle. The time of maximum precipitation is late afternoon to early evening in the interior, and midnight to early morning along the Agulhas Current as well as inland in the northeast of the county. The proximity of the warm Agulhas Current plays a role in the diurnal cycle of rainfall at coastal stations. There is an early morning maximum in precipitation in the South West of the country with small amplitude in the diurnal cycle there. On average, the peak in precipitation amount leads the peak in frequencies of precipitation by 30 min to 1 h. Together with a high resolution climatological summer rain rate presented here and a detailed table for all stations, this study is a benchmark upon which model output or satellite estimate of the diurnal cycle can be compared within the region.

Original languageEnglish (US)
Pages (from-to)770-777
Number of pages8
JournalInternational Journal of Climatology
Volume33
Issue number3
DOIs
StatePublished - Mar 15 2013

Fingerprint

rainfall
summer
harmonic analysis
coast
Africa
station
rain
county
rate

Keywords

  • Agulhas Current
  • Diurnal cycle
  • Precipitation
  • South Africa

ASJC Scopus subject areas

  • Atmospheric Science

Cite this

The diurnal cycle of rainfall in South Africa in the austral summer. / Rouault, Mathieu; Roy, Shouraseni Sen; Balling, Robert.

In: International Journal of Climatology, Vol. 33, No. 3, 15.03.2013, p. 770-777.

Research output: Contribution to journalArticle

Rouault, Mathieu ; Roy, Shouraseni Sen ; Balling, Robert. / The diurnal cycle of rainfall in South Africa in the austral summer. In: International Journal of Climatology. 2013 ; Vol. 33, No. 3. pp. 770-777.
@article{d381ece11b734653ae7d964390f07a4f,
title = "The diurnal cycle of rainfall in South Africa in the austral summer",
abstract = "The diurnal cycle of precipitation over South Africa during summer is analysed for the first time using hourly precipitation data from 103 stations for the period 1998-2007. Using harmonic analysis, we found the presence of a distinct diurnal cycle over most of South Africa regarding both the frequency and amount of precipitation events. The standardized amplitudes, indicative of the strength of the diurnal cycle across a region, are strongest over the interior and along the east coast of South Africa with up to 70{\%} explained variance associated with the diurnal cycle. The time of maximum precipitation is late afternoon to early evening in the interior, and midnight to early morning along the Agulhas Current as well as inland in the northeast of the county. The proximity of the warm Agulhas Current plays a role in the diurnal cycle of rainfall at coastal stations. There is an early morning maximum in precipitation in the South West of the country with small amplitude in the diurnal cycle there. On average, the peak in precipitation amount leads the peak in frequencies of precipitation by 30 min to 1 h. Together with a high resolution climatological summer rain rate presented here and a detailed table for all stations, this study is a benchmark upon which model output or satellite estimate of the diurnal cycle can be compared within the region.",
keywords = "Agulhas Current, Diurnal cycle, Precipitation, South Africa",
author = "Mathieu Rouault and Roy, {Shouraseni Sen} and Robert Balling",
year = "2013",
month = "3",
day = "15",
doi = "10.1002/joc.3451",
language = "English (US)",
volume = "33",
pages = "770--777",
journal = "International Journal of Climatology",
issn = "0899-8418",
publisher = "John Wiley and Sons Ltd",
number = "3",

}

TY - JOUR

T1 - The diurnal cycle of rainfall in South Africa in the austral summer

AU - Rouault, Mathieu

AU - Roy, Shouraseni Sen

AU - Balling, Robert

PY - 2013/3/15

Y1 - 2013/3/15

N2 - The diurnal cycle of precipitation over South Africa during summer is analysed for the first time using hourly precipitation data from 103 stations for the period 1998-2007. Using harmonic analysis, we found the presence of a distinct diurnal cycle over most of South Africa regarding both the frequency and amount of precipitation events. The standardized amplitudes, indicative of the strength of the diurnal cycle across a region, are strongest over the interior and along the east coast of South Africa with up to 70% explained variance associated with the diurnal cycle. The time of maximum precipitation is late afternoon to early evening in the interior, and midnight to early morning along the Agulhas Current as well as inland in the northeast of the county. The proximity of the warm Agulhas Current plays a role in the diurnal cycle of rainfall at coastal stations. There is an early morning maximum in precipitation in the South West of the country with small amplitude in the diurnal cycle there. On average, the peak in precipitation amount leads the peak in frequencies of precipitation by 30 min to 1 h. Together with a high resolution climatological summer rain rate presented here and a detailed table for all stations, this study is a benchmark upon which model output or satellite estimate of the diurnal cycle can be compared within the region.

AB - The diurnal cycle of precipitation over South Africa during summer is analysed for the first time using hourly precipitation data from 103 stations for the period 1998-2007. Using harmonic analysis, we found the presence of a distinct diurnal cycle over most of South Africa regarding both the frequency and amount of precipitation events. The standardized amplitudes, indicative of the strength of the diurnal cycle across a region, are strongest over the interior and along the east coast of South Africa with up to 70% explained variance associated with the diurnal cycle. The time of maximum precipitation is late afternoon to early evening in the interior, and midnight to early morning along the Agulhas Current as well as inland in the northeast of the county. The proximity of the warm Agulhas Current plays a role in the diurnal cycle of rainfall at coastal stations. There is an early morning maximum in precipitation in the South West of the country with small amplitude in the diurnal cycle there. On average, the peak in precipitation amount leads the peak in frequencies of precipitation by 30 min to 1 h. Together with a high resolution climatological summer rain rate presented here and a detailed table for all stations, this study is a benchmark upon which model output or satellite estimate of the diurnal cycle can be compared within the region.

KW - Agulhas Current

KW - Diurnal cycle

KW - Precipitation

KW - South Africa

UR - http://www.scopus.com/inward/record.url?scp=84873524970&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84873524970&partnerID=8YFLogxK

U2 - 10.1002/joc.3451

DO - 10.1002/joc.3451

M3 - Article

AN - SCOPUS:84873524970

VL - 33

SP - 770

EP - 777

JO - International Journal of Climatology

JF - International Journal of Climatology

SN - 0899-8418

IS - 3

ER -