Distinguishing southern Africa precipitation response by strength of El Niño events and implications for decision-making
December–February precipitation in southern Africa during recent El Niño events is studied by distinguishing circulation and precipitation responses during strong and moderate-to-weak events. We find that while both strong and moderate-to-weak El Niño events tend to dry southern Africa, the pattern...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2018-01-01
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| Series: | Environmental Research Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.1088/1748-9326/aacc4c |
| _version_ | 1797748242606194688 |
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| author | Catherine Pomposi Chris Funk Shraddhanand Shukla Laura Harrison Tamuka Magadzire |
| author_facet | Catherine Pomposi Chris Funk Shraddhanand Shukla Laura Harrison Tamuka Magadzire |
| author_sort | Catherine Pomposi |
| collection | DOAJ |
| description | December–February precipitation in southern Africa during recent El Niño events is studied by distinguishing circulation and precipitation responses during strong and moderate-to-weak events. We find that while both strong and moderate-to-weak El Niño events tend to dry southern Africa, the pattern and magnitude of precipitation anomalies in the region are different, with strong El Niño events resulting in rainfall deficits often less than −0.88 standardized units and deficits of only about half that for the moderate-to-weak case. Additionally, the likelihood of southern Africa receiving less than climatologic precipitation is approximately 80% for strong El Niño events compared to just over 60% for moderate-to-weak El Niño. Strong El Niño events are found to substantially disrupt onshore moisture transports from the Indian Ocean and increase geopotential heights within the Angola Low. Since El Niño is the most predictable component of the climate system that influences southern Africa precipitation, the information provided by this assessment of the likelihood of dry conditions can serve to benefit early warning systems. |
| first_indexed | 2024-03-12T16:02:06Z |
| format | Article |
| id | doaj.art-e60d721f72da4d54955149f14d0dd0a3 |
| institution | Directory Open Access Journal |
| issn | 1748-9326 |
| language | English |
| last_indexed | 2024-03-12T16:02:06Z |
| publishDate | 2018-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | Environmental Research Letters |
| spelling | doaj.art-e60d721f72da4d54955149f14d0dd0a32023-08-09T14:35:34ZengIOP PublishingEnvironmental Research Letters1748-93262018-01-0113707401510.1088/1748-9326/aacc4cDistinguishing southern Africa precipitation response by strength of El Niño events and implications for decision-makingCatherine Pomposi0https://orcid.org/0000-0001-6565-6228Chris Funk1Shraddhanand Shukla2Laura Harrison3Tamuka Magadzire4Climate Hazards Group, Department of Geography, University of California Santa Barbara , Santa Barbara, CA, United States of America; Author to whom any correspondence should be addressed.Climate Hazards Group, Department of Geography, University of California Santa Barbara , Santa Barbara, CA, United States of America; US Geological Survey, Center for Earth Resources Observation and Science (EROS) , SD, United States of AmericaClimate Hazards Group, Department of Geography, University of California Santa Barbara , Santa Barbara, CA, United States of AmericaClimate Hazards Group, Department of Geography, University of California Santa Barbara , Santa Barbara, CA, United States of AmericaClimate Hazards Group, Department of Geography, University of California Santa Barbara , Santa Barbara, CA, United States of America; Famine Early Warning Systems Network , Gabarone, BotswanaDecember–February precipitation in southern Africa during recent El Niño events is studied by distinguishing circulation and precipitation responses during strong and moderate-to-weak events. We find that while both strong and moderate-to-weak El Niño events tend to dry southern Africa, the pattern and magnitude of precipitation anomalies in the region are different, with strong El Niño events resulting in rainfall deficits often less than −0.88 standardized units and deficits of only about half that for the moderate-to-weak case. Additionally, the likelihood of southern Africa receiving less than climatologic precipitation is approximately 80% for strong El Niño events compared to just over 60% for moderate-to-weak El Niño. Strong El Niño events are found to substantially disrupt onshore moisture transports from the Indian Ocean and increase geopotential heights within the Angola Low. Since El Niño is the most predictable component of the climate system that influences southern Africa precipitation, the information provided by this assessment of the likelihood of dry conditions can serve to benefit early warning systems.https://doi.org/10.1088/1748-9326/aacc4cEl Niñoprecipitationearly warningsouthern Africa |
| spellingShingle | Catherine Pomposi Chris Funk Shraddhanand Shukla Laura Harrison Tamuka Magadzire Distinguishing southern Africa precipitation response by strength of El Niño events and implications for decision-making Environmental Research Letters El Niño precipitation early warning southern Africa |
| title | Distinguishing southern Africa precipitation response by strength of El Niño events and implications for decision-making |
| title_full | Distinguishing southern Africa precipitation response by strength of El Niño events and implications for decision-making |
| title_fullStr | Distinguishing southern Africa precipitation response by strength of El Niño events and implications for decision-making |
| title_full_unstemmed | Distinguishing southern Africa precipitation response by strength of El Niño events and implications for decision-making |
| title_short | Distinguishing southern Africa precipitation response by strength of El Niño events and implications for decision-making |
| title_sort | distinguishing southern africa precipitation response by strength of el nino events and implications for decision making |
| topic | El Niño precipitation early warning southern Africa |
| url | https://doi.org/10.1088/1748-9326/aacc4c |
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