Scientists find how ocean stores carbon

CSIRO

Share on print The scientists found that rather than carbon being absorbed uniformly into the deep ocean in vast areas, it is drawn down and locked away by plunging currents a thousand kilometres wide.  Image: andrej67/iStockphoto A team of British and Australian scientists has discovered how carbon is drawn down from the surface of the Southern Ocean to the deep waters beneath. The Southern Ocean is an important carbon sink in the world – around 40 per cent of the annual global CO2 emissions absorbed by the world’s oceans enter through this region. "Now that we have an improved understanding of the mechanisms for carbon draw-down we are better placed to understand the effects of changing climate and future carbon absorption by the ocean." Dr Jean-Baptiste Sallée, British Antarctic Survey. Reporting this week in the journal Nature Geoscience, scientists from British Antarctic Survey (BAS) and Australia’s national research agency, the Commonwealth Scientific and Industrial Research Organisation (CSIRO), reveal that rather than carbon being absorbed uniformly into the deep ocean in vast areas, it is drawn down and locked away from the atmosphere by plunging currents a thousand kilometres wide. Winds, currents and massive whirlpools that carry warm and cold water around the ocean – known as eddies – create localised pathways or funnels for carbon to be stored. Lead author, Dr Jean-Baptiste Sallée from British Antarctic Survey says, “The Southern Ocean is a large window by which the atmosphere connects to the interior of the ocean below. Until now we didn’t know exactly the physical processes of how carbon ends up being stored deep in the ocean. It’s the combination of winds, currents and eddies that create these carbon-capturing pathways drawing waters down into the deep ocean from the ocean surface.” “Now that we have an improved understanding of the mechanisms for carbon draw-down we are better placed to understand the effects of changing climate and future carbon absorption by the ocean.” CSIRO co-author, Dr Richard Matear says the rate-limiting step in the anthropogenic carbon uptake by the ocean is the physical transport from the surface into the ocean interior. “Our study identifies these pathways for the first time and this matches well with observationally–derived estimates of carbon storage in the ocean interior,” Dr Matear says. Due to the size and remote location of the Southern Ocean, scientists have only recently been able to explore the workings of the ocean with the help of small robotic probes – known as Argo floats. In 2002, 80 floats were deployed in the Southern Ocean to collect information on the temperature and salinity. This unique set of observations spanning 10 years has enabled scientists to investigate this remote region of the world for the first time. The floats are just over a metre in length and dive to depths of 2km. Today, there are over 3,000 floats in the oceans worldwide providing detailed information used in oceanic climate models. The team also analysed temperature, salinity and pressure data collected from ship-based observations since the 1990s. The instrument used for this is called a CTD profiler which is a cluster of sensors taking measurements as it’s lowered deep down into the ocean to depths of more than 7km. The work was supported through the Wealth from Oceans and Australian Climate Change Science Programs, and the Australian Government’s Cooperative Research Centre program. Editor's Note: Original news release can be found here.

Learning patterns aid computers

CHARLES STURT UNIVERSITY

Share on print While computers are good at face recognition, they're quite weak at 'thinking', particularly common sense. The researchers found that patterns humans use to learn could also benefit artificial intelligence.  Image: Henrik5000/iStockphoto Patterns needed to help computers think better have been investigated by an international research group including a Charles Sturt University (CSU) expert, with the results reported in the latest issue of the international journalNature Scientific Reports.   The results come from ten years of collaboration between the Director of CSU’s Centre for Research in Complex Systems, Professor Terry Bossomaier, and the University of Sydney.   “We want to understand how shifts in paradigm occur in human thinking. These shifts occur in individuals when they reach their performance in such areas as mathematics or finance. In societies they occur as knowledge grows and attitudes change,” Professor Bossomaier said.   “One challenge we faced was to find ways of measuring these shifts. We decided to use the ancient oriental game of Go and study how experts in Go use patterns to remember strategies for the game, and how these might be simulated in a computer program.   “Computers are currently quite good at face recognition, but voice and speech processing still have some way to go. In areas of what we call ‘thinking’, particularly common sense, computers are still quite weak,” Professor Bossomaier said.   “One big difference between human thinking and current computational intelligence is that we use a big library of patterns we build up over the years to give us a fast intuitive grasp of a situation.   “The great cognitive scientist Herbert Simon, who won the Nobel Prize for Economics, recognised this as needing to build up chunks of little patterns, and needing at least 50,000 of these to reach expert level at anything. We now think it is more than 100,000 patterns.”   The research project aimed to develop a deeper understanding of how these chunks are gained and how they change with experience.   “We also wanted to capture decisions made in the real world, without the restrictive effects of being in an artificial experiment. We decided to do this by capturing the moves made in high level games played online, such as Go,” Professor Bossomaier said.   Chess was the domain of study for human expertise, but after the Deep Blue computer defeated then World Champion Gary Kasparov in 1997, interest has turned to other games of skill.   “Go is as old as Chess and is played extensively in Asia, especially in Japan and Korea. Human players are still much better than computers. This is an excellent game to study to learn more about what humans do really well,” he said.   The first phase of the research showed that people's knowledge undergoes dramatic reorganisation when they move from amateur to professional rank.   “The change takes place not just in the areas of ‘deep strategy’, where one would expect the big gains to be, but also there is a radical reorganisation at the perceptual level,” Professor Bossomaier said. “It's a bit like acquiring a good accent in a foreign language. At quite a young age, the sounds of one's first language get set and are very difficult to change later.   “The perceptual templates we found for Go are akin to the ‘phonemes’ or sounds of a language. But unlike language, we found that these low-level templates do change with many years of practice.”   Professor Bossomaier believes this also has major implications for education. “Getting the building blocks right is the key to developing expertise. If we can find these blocks, the templates used by the superstars, we might be able to build them into the early training of professionals. “Computer games are also being increasingly used in education and training. Insights from studying the most difficult games such as Go can also be fed back into more serious games,” he said. Editor's Note: Original news release can be found here.

New hope for challenging kids

THE UNIVERSITY OF SYDNEY

Share on print Parents of young children who show extreme behaviour problems and a lack of empathy or remorse may find new hope from research at the University of Sydney. "We found that the quality of a parent's emotional interaction and attachment with a young child is crucial to predicting if that child will develop this high-risk pattern of behaviour," said Dr David Hawes, the research leader from the School of Psychology at the University. "Based on our findings we can now test early-intervention strategies to help these parents and their children." Children who from an early age show a fearless temperament and do not show interest in other people's emotions, especially when they are upset or in need of help, are known to researchers as having "callous-unemotional" (CU) traits. These children typically also lack guilt or concern about behaviours that would produce guilt in most children. "While most children with conduct problems do not show CU traits, those who do are at greater risk for ongoing problems - particularly aggression. These children are indifferent to punishment for poor behaviour and in fact the more severe the punishment the worse the behaviour becomes," said Dr Hawes. Callous-unemotional behaviour has been shown to be a strong indicator of psychopathic behaviour and violent crime in adulthood. Dr Hawes and his colleagues have just completed a four-year study, funded through the Australian Research Centre, looking at children aged two to four with CU traits. The research was unusual in concentrating on very young children and being based primarily on direct observation. It used video analysis to evaluate the quality of interactions and attachment between mothers and children. "The study suggests that the emotional bonds between mothers and their children strongly predict if they will show high levels of CU traits, as well as conduct problems," said Dr Hawes. Until recently the quality of a child's parenting was not believed to have an impact on either callous-unemotional or the behaviour of children with such traits, but this research suggests that strengthening the emotional bonds between parents and their infants can make a difference. "While CU characteristics seem to be largely under the control of genetics if a child receives consistent and warm parenting in a secure family environment it can protect against those traits. This aspect of parenting is still relevant in terms of influencing the traits even though it is not the cause. "In fact its protective effects - its ability to prevent the development of aggressive and oppositional behaviour - also appear to be strongest for children with the highest level of CU traits." The main implication of the study is that CU children benefit less from current parenting interventions for conduct problems because they are focused on reducing negative parenting instead of on the quality of the parenting relationship. "While research with older children and adolescents has previously shown that CU traits are associated with more severe behaviour problems regardless of harsh and inconsistent discipline, our research suggests that this may not be the case in early childhood. Most importantly however, we found that it was only among the CU children that having an emotionally warm relationship protected against conduct problems." The researchers now plan to evaluate programs specifically aimed at improving quality of attachment by employing strategies shown by the current study to be highly beneficial. They include emphasising eye contact during emotional interactions, giving the child language to express emotion and the skills to identify emotion in other people. "Parents with very difficult-to-handle children might be told it is a phase - the terrible twos - but that does not apply for children at risk of antisocial behaviour. For them the earlier we can address the issue the better. "For our research we were in the privileged position of being able to work with Karitane, one of the only community health services in the world which specialises in clinically significant behaviour problems in very young children." Editor's Note: Original news release can be found here.