Advancing climate prediction in the Tropical Atlantic

Buoys of the Prediction and Research Moored Array in the Tropical Atlantic (PIRATA)

Thanks to a grant from the National Research Foundation (NRF), I attended the 2013 CLIVAR Tropical Atlantic Variability (TAV) Prediction and Research Moored Array in the Tropical Atlantic (PIRATA) Meeting in Venice, Italy. I also had the opportunity to discuss the then upcoming PREFACE (Enhancing PREdiction oF Tropical Atlantic ClimatE and its impact) project.

The grant, a South African/Angolan bilateral grant, is led by Dr Juliet Hermes, Manager of the SAEON Egagasini Node, with me as a co-investigator on the project.

For the past 15 years, the CLIVAR community has undertaken observational and modelling efforts in the Tropical Atlantic to better understand the processes responsible for Tropical Atlantic climate variability; to provide a basis for assessment and improvement of coupled ocean-atmosphere models; and to advance climate predictability in the surrounding regions. The scientific foundations of these efforts include the Prediction and Research Moored Array in the Tropical Atlantic (PIRATA), which was launched in 1997 and the Tropical Atlantic Climate Experiment (TACE), which spanned the period from 2006-2012.

Observing and predicting Tropical Atlantic climate

The Tropical Atlantic Variability Meeting was held jointly with the PIRATA-18 Meeting to address progress in observing, simulating, understanding and predicting Tropical Atlantic climate. Topics of interest included the following themes: Climate variability and change in the Tropical Atlantic, Tropical Atlantic teleconnections, Predictability, Coupled and uncoupled model biases, Oceanic and atmospheric processes affecting climate variability, Physical-Biogeochemical interaction, Link between the Benguela upwelling and the Tropical Atlantic and Benguela Niños.

Kizomba ATLAS mooring off Angola

I also went to Venice in my capacity as chairman of the PIRATA South-East extension committee, of which Juliet Hermes is a member, where I reported on the successful deployment of the PIRATA extension Kizomba ATLAS mooring off Angola. Kizomba is the name of a dance in Angola - all PIRATA mooring is called after a dance. After a successful one-year pilot project, this location is now permanent and part of the main PIRATA array. This is also a contribution to the Global Climate Observing System. Funding for the mooring is obtained from the European FP7 project PREFACE, led by Prof. Keenlyside from Norway and of which I am a principal investigator.

The Kizomba mooring was deployed successfully at 8 East, 6 South by French collaborators Bernard Bourles from IRD . Data is available for free in real time at http://www.pmel.noaa.gov/pirata/6s8e.html.

For the past 15 years, the CLIVAR community has undertaken observational and modelling efforts in the Tropical Atlantic to advance climate predictability in the surrounding regions (Image courtesy of CLIVAR)

The meeting was also used to prepare for the FP7 PREFACE project, which involves South Africa, Angola, Namibia, Senegal, the Ivory Coast, Nigeria, Benin, Norway, France, Germany, Spain, Italy and the UK. The PREFACE project seeks to enhance prediction in the Tropical Atlantic and adjacent upwelling and, among other topics, focuses on Benguela Niños, the Benguela upwelling and their connection to the Tropical Atlantic. The kick-off meeting was held in Madrid in December last year.

Shifts of great socio-economic importance

In a nutshell, the Tropical Atlantic climate recently experienced pronounced shifts of great socio-economic importance. The oceanic changes were the largest in the eastern boundary upwelling systems, such as the Angola Benguela upwelling system. African countries bordering the Atlantic strongly depend upon the ocean for societal development, fisheries and tourism. They were strongly affected by these climatic changes and will face important adaptation challenges associated with global warming.

Climatic importance

Furthermore, these upwelling regions are also of great climatic importance, playing a key role in regulating global climate. Paradoxically, the Tropical Atlantic and adjacent upwelling regions are a region of key uncertainty in the earth-climate system: state-of-the-art climate models exhibit large systematic error, climate change projections are highly uncertain, and it is largely unknown how climate change will impact marine ecosystems.

PREFACE aims to address these interconnected issues. To meet these goals, PREFACE brings together European and African expertise to combine regional and global scale modelling capabilities, field experiments and observation systems. The target region includes areas more affected by climate change and by its consequences, European outermost regions, and African countries bordering the Atlantic.