Anthropogenic influence on the drivers of the Western Cape drought 2015–2017
In the period 2015–2017, the Western Cape region has suffered from three consecutive years of below average rainfall—leading to a prolonged drought and acute water shortages, most prominently in the city of Cape Town. After testing that the precipitation deficit is the primary driver behind the redu...
| Main Authors: | , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2018-01-01
|
| Series: | Environmental Research Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.1088/1748-9326/aae9f9 |
| _version_ | 1797748165368086528 |
|---|---|
| author | Friederike E L Otto Piotr Wolski Flavio Lehner Claudia Tebaldi Geert Jan van Oldenborgh Sanne Hogesteeger Roop Singh Petra Holden Neven S Fučkar Romaric C Odoulami Mark New |
| author_facet | Friederike E L Otto Piotr Wolski Flavio Lehner Claudia Tebaldi Geert Jan van Oldenborgh Sanne Hogesteeger Roop Singh Petra Holden Neven S Fučkar Romaric C Odoulami Mark New |
| author_sort | Friederike E L Otto |
| collection | DOAJ |
| description | In the period 2015–2017, the Western Cape region has suffered from three consecutive years of below average rainfall—leading to a prolonged drought and acute water shortages, most prominently in the city of Cape Town. After testing that the precipitation deficit is the primary driver behind the reduced surface water availability, we undertake a multi-method attribution analysis for the meteorological drought, defined in terms of a deficit in the 3 years running mean precipitation averaged over the Western Cape area. The exact estimate of the return time of the event is sensitive to the number of stations whose data is incorporated in the analysis but the rarity of the event is unquestionable, with a return time of more than a hundred years. Synthesising the results from five different large model ensembles as well as observed data gives a significant increase by a factor of three (95% confidence interval 1.5–6) of such a drought to occur because of anthropogenic climate change. All the model results further suggest that this trend will continue with future global warming. These results are in line with physical understanding of the effect of climate change at these latitudes and highlights that measures to improve Cape Town’s resilience to future droughts are an adaptation priority. |
| first_indexed | 2024-03-12T16:02:01Z |
| format | Article |
| id | doaj.art-d4aec89f7b104bc8be357d37aeaece92 |
| institution | Directory Open Access Journal |
| issn | 1748-9326 |
| language | English |
| last_indexed | 2024-03-12T16:02:01Z |
| publishDate | 2018-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | Environmental Research Letters |
| spelling | doaj.art-d4aec89f7b104bc8be357d37aeaece922023-08-09T14:37:27ZengIOP PublishingEnvironmental Research Letters1748-93262018-01-01131212401010.1088/1748-9326/aae9f9Anthropogenic influence on the drivers of the Western Cape drought 2015–2017Friederike E L Otto0https://orcid.org/0000-0001-8166-5917Piotr Wolski1Flavio Lehner2Claudia Tebaldi3https://orcid.org/0000-0001-9233-8903Geert Jan van Oldenborgh4https://orcid.org/0000-0002-6898-9535Sanne Hogesteeger5Roop Singh6Petra Holden7Neven S Fučkar8Romaric C Odoulami9Mark New10https://orcid.org/0000-0001-6082-8879Environmental Change Institute, University of Oxford , OX1 3QY Oxford, United KingdomClimate System Analysis Group, University of Cape Town , South AfricaClimate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO, United States of AmericaClimate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO, United States of AmericaKNMI, De Bilt, The NetherlandsRed Cross Red Crescent Climate Centre, The Hague, NetherlandsRed Cross Red Crescent Climate Centre, The Hague, NetherlandsAfrican Climate and Development Initiative, University of Cape Town , South AfricaEnvironmental Change Institute, University of Oxford , OX1 3QY Oxford, United Kingdom; Barcelona Supercomputing Center (BSC), Barcelona, SpainAfrican Climate and Development Initiative, University of Cape Town , South AfricaAfrican Climate and Development Initiative, University of Cape Town , South Africa; School of International Development, University of East Anglia , Norwich, United KingdomIn the period 2015–2017, the Western Cape region has suffered from three consecutive years of below average rainfall—leading to a prolonged drought and acute water shortages, most prominently in the city of Cape Town. After testing that the precipitation deficit is the primary driver behind the reduced surface water availability, we undertake a multi-method attribution analysis for the meteorological drought, defined in terms of a deficit in the 3 years running mean precipitation averaged over the Western Cape area. The exact estimate of the return time of the event is sensitive to the number of stations whose data is incorporated in the analysis but the rarity of the event is unquestionable, with a return time of more than a hundred years. Synthesising the results from five different large model ensembles as well as observed data gives a significant increase by a factor of three (95% confidence interval 1.5–6) of such a drought to occur because of anthropogenic climate change. All the model results further suggest that this trend will continue with future global warming. These results are in line with physical understanding of the effect of climate change at these latitudes and highlights that measures to improve Cape Town’s resilience to future droughts are an adaptation priority.https://doi.org/10.1088/1748-9326/aae9f9extreme event attributiondroughtclimate change |
| spellingShingle | Friederike E L Otto Piotr Wolski Flavio Lehner Claudia Tebaldi Geert Jan van Oldenborgh Sanne Hogesteeger Roop Singh Petra Holden Neven S Fučkar Romaric C Odoulami Mark New Anthropogenic influence on the drivers of the Western Cape drought 2015–2017 Environmental Research Letters extreme event attribution drought climate change |
| title | Anthropogenic influence on the drivers of the Western Cape drought 2015–2017 |
| title_full | Anthropogenic influence on the drivers of the Western Cape drought 2015–2017 |
| title_fullStr | Anthropogenic influence on the drivers of the Western Cape drought 2015–2017 |
| title_full_unstemmed | Anthropogenic influence on the drivers of the Western Cape drought 2015–2017 |
| title_short | Anthropogenic influence on the drivers of the Western Cape drought 2015–2017 |
| title_sort | anthropogenic influence on the drivers of the western cape drought 2015 2017 |
| topic | extreme event attribution drought climate change |
| url | https://doi.org/10.1088/1748-9326/aae9f9 |
| work_keys_str_mv | AT friederikeelotto anthropogenicinfluenceonthedriversofthewesterncapedrought20152017 AT piotrwolski anthropogenicinfluenceonthedriversofthewesterncapedrought20152017 AT flaviolehner anthropogenicinfluenceonthedriversofthewesterncapedrought20152017 AT claudiatebaldi anthropogenicinfluenceonthedriversofthewesterncapedrought20152017 AT geertjanvanoldenborgh anthropogenicinfluenceonthedriversofthewesterncapedrought20152017 AT sannehogesteeger anthropogenicinfluenceonthedriversofthewesterncapedrought20152017 AT roopsingh anthropogenicinfluenceonthedriversofthewesterncapedrought20152017 AT petraholden anthropogenicinfluenceonthedriversofthewesterncapedrought20152017 AT nevensfuckar anthropogenicinfluenceonthedriversofthewesterncapedrought20152017 AT romariccodoulami anthropogenicinfluenceonthedriversofthewesterncapedrought20152017 AT marknew anthropogenicinfluenceonthedriversofthewesterncapedrought20152017 |