UFH's Prof Werner Nel leads research expedition in sub-Antarctica

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Prof Werner Nel, Physical Geography Professor and NRF C-rated Researcher at the University of Fort Hare recently returned from sub-Antarctica where he led a team of researchers who are investigating the interactions between landscape and climate in the region. 

The research project titled: Landscape and climate interactions in the sub-Antarctic is an ongoing project that started in 2015 and a continuation of earth sciences projects that have been running on Marion Island since 1996. Prof Nel joined the project in 1999 as a field assistant. He is currently its Chief Scientist.
 
The team recently published a paper that reviews the history of earth sciences research on Marion Island: https://www.tandfonline.com/doi/abs/10.1080/03736245 .2020.1786445. 
 
This latest project, which will run until 2023, is a multinational project with collaborators from the University of South Africa, University of Free State, University of Johannesburg, the British Antarctic Survey and the Scottish Universities Environment Research Centre. It is funded by the National Research Foundation through the South African National Antarctic Programme (SANAP).
 
After a heavy fieldwork schedule, Prof Nel and his team sailed back to South Africa in mid-May. 
 
In the latest edition of ThisWeek@FortHare, Prof Nel gives readers a glimpse into his 21-year-old research project, the recent research expedition and his adventurous experience on the field.
 
Please tell us more about your recent research expedition in sub-Antarctica?
 
In the Southern Hemisphere, the sub-Antarctic islands provide the only terrestrial record of Quaternary glaciations and climate within thousands of kilometres of ocean. 
 
The current project will investigate the interactions between landscape and climate in the sub-Antarctic through obtaining the ages of the basaltic lava (through Uranium-series dating) to place it within a geological chronology that constrains landscape development and glaciation on Marion Island. 
 
We will also define Marion Island’s glacial history within more accurate temporal and spatial scales by using cosmogenic 36Cl surface exposure dating to explain how deglaciation has facilitated landscape development and affected the colonisation and dispersal of biota.
 
Furthermore, we want to quantify changes in the Southern Hemisphere Westerly Wind regime during the last major reorganization of the climate system (Termination 1: 18,000–11,000 years ago) to assist in determining how changes in the strength and position of the Southern Hemisphere Westerly Wind belt have impacted on the ability of the Southern Ocean to modulate CO2. This will be done through analysis of novel dust and sea salt aerosol proxies in peat deposits on Marion Island and Gough Island.
 
Lastly, we will also determine how aspects of the contemporary landscape (aeolian landforms) interact with the current dominant westerly wind patterns to predict future landform change.
 
Why does this study matter? 
 
Sub-Antarctic islands are extremely sensitive to climatic change and landscapes of these islands can be considered proxies of past global climate shifts and identifiers of current climate change. The only terrestrial record of Quaternary glaciations in the Southern Ocean reside within the landscapes of these small islands and provide a window to understand climate and ocean regimes of the past. 
 
It is becoming more evident that research that focuses on the geochronology and glacial history of these islands as individual record keepers will have global significance. We have recently published a piece in The Conversation about the importance of this and it can be seen here: https://theconversation.com/marion-islandslast-ice-age-happened-earlier-...
 
The capacity of the Southern Ocean to absorb anthropogenic CO2 is limited by an observed increase in the strength of the Southern Hemisphere Westerly Wind (SHW), which modulates both the upwelling and outgassing of CO2. This means that the ocean may no longer function as such an efficient net sink of CO2, driving up atmospheric greenhouse gases and accelerating rates of global warming. The migration of the westerly wind belt is also associated with changes in Southern Ocean circulation and sea surface temperatures and moisture delivery. 
 
Our research will reconstruct past changes in the strength and position of the SHW to assess the range of natural variability and evaluate how the SHW have modulated the CO2 sink in the past and influenced moisture delivery and hence the timing of glaciation in the sub-Antarctic which is now a major priority for global palaeoclimate science. 
 
Furthermore, the observed increase in the current strength of the (SHW) and recent climatic amelioration in the sub-Antarctic may exacerbate contemporary wind-driven processes in the sub-Antarctic with a clear impact on ecosystem functioning. 
 
Why did you want to do this study? 
 
I had the opportunity to overwinter on Marion Island in 1999 (as a field assistant) when I was an Honours student at the University of Pretoria. 
 
My main motivation for taking on the job was centred purely on the opportunity for adventure. The science for me at that time was secondary - typical student behaviour I would say. 
 
I completed my Honours and Masters fieldwork during my 13 months overwintering stint on the island and the time I spent on the island doing field research was life-changing. I was taken by the Island and the opportunity it can afford a young researcher and I have been very fortunate to have been involved in earth sciences research on Marion Island ever since, first as a student and then as a collaborator. Our work on Marion Island defined my research career ever since I set foot on the island up to the point now where I am the Principal Investigator of the project.
 
 
How does this study relate to your other work? 
 
Even though my research in the sub-Antarctic is my main research focus currently, I am principally involved in two other international research projects/collaborations. I am one of the main collaborators (with Prof Paul Sumner, University of Pretoria) on a research project based in the Mascarenes Islands of Mauritius and Ile le Rond (Round Island). The research is in conjunction with the University of Mauritius, Mauritian Wildlife Foundation the Mauritius Oceanographic Institute (MOI) and the Mauritius National Parks and Conservation Services (NPCS). 
 
The project originally started as an investigation into the erosivity of high-intensity rainfall on Mauritius. However, it has evolved into a multi-faceted project investigating erosivity (wind and rain) as well as soil conservation and coastal risk assessment principally on Mauritius but also on the offshore islets like Round Island. 
 
Then I am also currently involved in a collaboration with colleagues from Nanjing University in China. This project is part of a collaboration funded by the National Natural Science Foundation of China and the NRF through the Research Cooperation Programme in Geosciences. 
 
Our part of the project is to investigate the effects of weathering and human activities on heavy metal pollution in China’s Pearl River Basin. The works are all related in that even though the environments are different the geomorphic processes we investigate (like erosivity and weathering) are very similar.
 
Lastly, please share with us your experiences whilst doing fieldwork? 
 
Well, I have been involved in this research for 21 years so there have been many adventures and experiences over time. The most recent research expedition was my 14th expedition to Marion Island (I also spent a summer in the Antarctic in 2010/2011) so there are many stories of adventures and misadventures to tell. 
 
It is a very harsh environment to work in. It is very cold, windy and wet and all our fieldwork expeditions always turn out to be mini-adventures with some sort of challenge that needs to be overcome. It is difficult to explain to someone who has not been there how difficult it is to work in this environment. You have to walk long distances and be prepared to spend a substantial amount of time outdoors in a very harsh environment. 
 
However, for me, the best experience is taking a student to the island for the first time and see how they develop into a hardened islander who is not afraid of anything. All our current students have overwintered or are overwintering on the island. Abu Nguna (who is currently busy with his PhD) overwintered in 2015/2016 and again in 2018/2019 as part of his MSc. Sbu Sinuka also a current PhD student overwintered for his MSc in 2017/2018 and Zenande Kabase who is busy with his Masters project is currently on the island until May 2022. 
 
To be able to afford these students the same opportunities I enjoyed as a student (being involved in research in the sub-Antarctic) is the best experience for me and the main reason why we do what we do.