Role of the Southern Ocean in the Earth System (RoSES)
The Southern Ocean is one of the most important and poorly understood components of the global carbon cycle that profoundly shapes Earth's climate. It is the primary hot spot for the oceanic sink of anthropogenic carbon dioxide (CO2), having captured half of all human-related carbon that has entered the ocean to date. As a major knowledge gap and a central player in global carbon and climate dynamics, the Southern Ocean carbon system is regularly singled out as the Achilles' heel of the Earth system models upon which humankind relies to understand contemporary climate change, predict its future evolution, and define international climate policy.
NERC is investing £7 million in this five-year research programme, which aims to substantially reduce uncertainty in 21st century global climate change projections through improved assessment of the Southern Ocean carbon sink and to provide the scientific basis to inform international climate policy on the role of the Southern Ocean in 21st century global climate change.
The Southern Ocean (SO) is one of the most important and poorly understood components of the global carbon cycle that profoundly shapes Earth's climate. It is the primary hot spot for the oceanic sink of anthropogenic CO2, having captured half of all human-related carbon that has entered the ocean to date. This vast anthropogenic perturbation to the SO carbon system is activating a range of complex climate feedbacks (eg a rising atmospheric CO2-induced acceleration of the westerly winds over the SO, which may in turn be driving increased SO outgassing and raising atmospheric CO2 concentrations further) that are likely to exert a decisive control on the evolution of oceanic carbon uptake, atmospheric CO2 and global climate over the 21st century. Many of these climate feedbacks are poorly understood and quantified, yet evidence from our planet's past global climatic transitions (eg the end of the last glacial period) suggests that they can induce changes in atmospheric CO2 as large as those caused by human activities since the industrial revolution.
As the focus of major knowledge gaps and a central player in global carbon and climate dynamics, the SO carbon system is regularly singled out as the "Achilles' heel" of the Earth system models upon which humankind relies to understand contemporary climate change, predict its future evolution, and define international climate policy.
Inadequate understanding and unconstrained model representation of the SO carbon system constitute a critical uncertainty in climate projections for the 21st century. Investigations of the present magnitude of the SO carbon sink and its recent decadal variability yield wildly different estimates, yet unanimously show that the regional budget is the sum of large, uncertain outgassing and uptake terms that are both comparable in magnitude to the CO2 emissions from the world's most polluting economies and highly sensitive to climate change.
In the recent Paris Agreement - external link, 195 nations committed to undertaking rapid reductions in their greenhouse gas emissions to hold the global-mean temperature to well below 2°C above pre-industrial levels, recognising that this would significantly reduce the risks and impacts of climate change. The effectiveness of this agreement is, however, acutely vulnerable to future changes in the SO carbon system that are not captured by rudimentary representations in the present generation of Earth system models. Even modest variations in the SO's outgassing or uptake terms may lead to a significant shift in the reduction of global anthropogenic CO2 emissions required to meet long-term temperature goals, and produce a geopolitically challenging imbalance between the integral of national sources and the desired evolution of atmospheric carbon.
The evolution of the SO carbon sink over the 21st century has been the subject of a persistent, heated debate in the scientific literature. This is reflected in the SO accounting for most of the uncertainty in Earth system model predictions of global oceanic carbon uptake, which differ by up to approximately two billion metric tonnes of carbon per year (ie the present net global oceanic carbon uptake) by 2050. The debate is fuelled by a paucity of essential carbon system observations in the SO, which makes the region the most glaring biogeochemical 'data desert' in the world ocean; and by a damaging lack of understanding of the fundamental processes controlling the size of the SO carbon sink, which raises large uncertainties in the nature and magnitude of associated climate feedbacks - particularly as global emissions start to decline toward zero.
Now, the advent of novel autonomous robotic platforms and biogeochemical micro-sensor technologies, in which the UK has played a world-leading role, makes it possible to tackle these issues directly for the first time, and settle the debate once and for all.
The overarching objective of RoSES is to provide the scientific basis to inform international climate policy on the role of the Southern Ocean carbon system in 21st century global climate change. By substantially reducing uncertainty in 21st century global climate change projections through improved assessment of the Southern Ocean carbon sink, RoSES will bolster the UK's capacity to credibly encourage other nations to strengthen their emission reduction ambitions through the five-year review and 'ratchet' mechanism.
2017 - 2022
Can I apply for a grant?
A call for proposals for RoSES - Challenge 3 is open until 19 September 2019.
This programme has a budget of £7 million.
Proposals were invited for activities under the RoSES research programme. A moderating panel met on 7 April 2017 to assess the proposals.
The following documents and links are related to or give more information about this programme.