International speakers from the US, France, and Norway will talk about their oceanography research at UNSW Sydney.
International speakers from the US, France, and Norway will talk about their oceanography research at UNSW Sydney.
Abstracts are invited for a special session on Big Data in Oceanography and Meteorology at the annual meeting of the Australian Meteorological & Oceanographic Society (AMOS) and the International Conference on Tropical Meteorology and Oceanography (ICTMO), held in Darwin, NT, from 11-15 June 2019.
AMOS-ICTMO 2019 will bring together experts in meteorology, oceanography, climate, and other related sciences from Australia and around the world as well as government representatives, NGOs, businesses and the media to focus on the latest research.
The following special session on big data will be convened by Moninya Roughan, Shane Keating, and Steefan Contractor. Abstracts for oral and poster presentations are to be submitted via the AMOS-ICTMO 2019 submission site. The deadline for submission is Sunday 18 November 2018.
Big Data in Oceanography and Meteorology: Challenges, Applications, and Data Products
Oceanographers and meteorologists are drowning in a tide of data. Data availability has increased steadily in recent years due to the move towards higher resolution modelling and the increase in observations. Observational density has increased because of an increase in frequency of measurements, introduction of new single and multi-instrument datasets and new remote-sensing platforms. As a result, studies of geophysical fluid dynamics are becoming increasingly data driven. In order to derive valuable insights and knowledge from large volumes of data, new methods and techniques are emerging in the field of big data for visualization, analysis, and data dispensation. Vast numbers of datasets are being published and released freely for analysis and sharing.
We invite talks that are broadly related to the field of big data and data products. We encourage presentations on analysis of data from the syntheses of programmes such as IMOS and CMIP5 analyses, projects that deliver products and insights to end users, or that focus on pattern analysis and identification of complex relationships, predictive modelling using supervised and unsupervised algorithms, tools for handling large datasets and for increasing computational efficiency, novel applications of statistical learning and high volume time series analysis, blending of diverse datasets, reproducibility of analysis, inherent structural uncertainties in data, best practices in big datasets and guidance on recommended use for new and existing datasets.
A new research project led by the NZ MetService’s oceanography division, MetOcean Solutions, will examine the role of ocean circulation on New Zealand’s seafood sector.
The Moana Project was awarded $11.5 million over five years from the NZ Government Endeavour Fund, which invests in scientific research that positively benefits New Zealand’s economy, environment, and society. The proposal was led by MetOcean Solutions’ Chief Scientist Professor and UNSW Associate Professor Moninya Roughan.
“The Tasman Sea is warming at one of the fastest rates on Earth, four times the global average,” said Professor Roughan, “yet we currently have limited ability to comprehensively measure, monitor and predict the state of New Zealand’s oceans. This programme will create a new, dynamic and more integrated marine knowledge base – reducing uncertainty, maximising opportunity and preparing for future ocean changes.”
The Moana Project is a cross-institutional programme involving oceanographic research organisations, universities, and end-users in industry and government across New Zealand. The team will also collaborate with international experts from UNSW Sydney and the United States.
The project will improve understanding of coastal ocean circulation, connectivity and marine heatwaves to provide information that will support sustainable growth of the seafood industry (Māori, fisheries and aquaculture). Project partners will apply the internet of things concept to develop a low-cost ocean temperature profiler that will be deployed by the fishing communities ‘on all boats, at all times’. New Zealand’s first open-access ocean forecast system will be delivered by developing new ocean circulation models using a combination of advanced numerics, modern genomics and data from smart ocean sensors.
The project will investigate the drivers and impacts of marine heatwaves so that they can be predicted, and investigate ocean transport pathways and population connectivity of seafood species. This project will provide a step-change in the oceanic information available to the seafood sector and the broader community, accessible through the open-access user-friendly datasets and tools developed.
Professor Roughan says: “We are partnering with the seafood sector to develop a low-cost ocean sensor that will revolutionise ocean data collection. The sensors will be deployed throughout New Zealand’s exclusive economic zone with support from the commercial fishing sector.”
The Endeavour Fund aims to promote Vision Mātauranga, the New Zealand Government’s science policy framework to unlock the science and innovation potential of Māori knowledge (mātauranga), resources and people for the benefit of all New Zealanders. The Moana Project is anchored in mātauranga Māori through the partners’ relationship with the Whakatōhea Māori Trust Board, facilitating exchange of oceanographic knowledge between Māori and western science.
ARC Future Fellow Dr Bishak Gayen (ANU) will discuss his research in the M4PE seminar at UNSW Sydney on Monday 27 August 2018.
Title: Spanning 10 billion scales from millimetre turbulence to global circulation
Speaker: Bishakhdatta Gayen (Australian National University)
Date & Time: 4pm, Monday 27 August 2018. (Seminar will be followed by refreshments.)
Location: Red Centre room RC-3085, School of Mathematics and Statistics, UNSW Sydney
Abstract: The general ocean circulation, of crucial importance to the global climate, involves fluid motion on scales ranging from turbulence, internal waves, eddies and fronts, planetary Rossby waves and basin-scale gyre recirculation. Equilibrium is maintained between continuous large-scale forcing and energy dissipation. Understanding the physics of various dissipation mechanisms is important for improving the dynamical description of large-scale circulation. Large-scale ocean models do not accurately model turbulent convection, breaking waves, and turbulence, providing motivation to develop a better understanding of these mechanisms. In this presentation, my primary focus will be on understanding the role of turbulence and convection in ocean circulation.
In order to examine the effect of convection in ocean circulation, we have developed a model of circulation with flow driven by surface buoyancy in a closed basin using Direct Numerical Simulations. The circulation cell involves a horizontal boundary flow, turbulent plume motion and week interior return flow. We show that under planetary rotation, even in the absence of wind stress, the flow becomes three-dimensional with small-scale deep convection and broad basin-scale gyres. For the first time, DNS is used to model this circulation and quantify the heat transfer and flow energetics, demonstrating several dynamical regimes. I will also discuss the role of turbulent convection in melting of basal ice shelves and circulation around the Antarctic basin.
About the speaker: Dr Bishakhdatta Gayen is a Research Fellow at the Research School of Earth Sciences at Australian National University. His current research interests are nonlinear internal waves in the ocean, turbulent convection, modeling of Antarctic ice melting and Southern ocean dynamics. Bishak is a 2018 ARC Future Fellow, and has previously been awarded a 2013 ARC DECRA Fellowship. He has also received the RJL Hawke post-doctoral fellowship from the Australian Antarctic Science Program to study subsurface melting of ice shelves around Antarctica with implications for future sea-level rise.
About the main image: A snapshot from simulation of circulation in a closed ocean basin forced by imposed constant temperature having a variation with latitude, showing the kinetic energy on a horizontal plane near the upper boundary, temperature contours on a vertical section near the western boundary and vertical velocity on a vertical section near the northern boundary. Time averaged near-surface transport streamfunction is shown above.
A recent study by researchers at UNSW Sydney and the UK National Oceanography Centre has revealed how ocean warming has changed the pattern of salinity observed at the surface of the ocean. Their results, published last month in Environmental Research Letters, have significant implications for our ability to measure changes to Earth’s water cycle in a changing climate.
Changes in ocean salinity – the concentration of salt in the ocean – is an important signature of past changes in the water cycle. Over a given area of the ocean, net evaporation increases salt concentration, while net precipitation lowers salt concentration. Observed changes in surface salinity reveal global warming trends: in particular, regions of the globe with high salinity are become more salty, while regions that have low salinity are become less salty.
Figure (a) Mean fresh water flux out of the ocean from reanalysis data. (b) Mean sea surface salinity from observational analysis. From Zika et al. Environmental Research Letters (2018).
This has led climate scientists to think of the ocean itself as a “rain gauge” that can reveal historical changes in the water cycle, which is tightly linked to climate change. Global climate models project overall increases in evaporation and precipitation and rainfall extremes, with wet regions of the globe getting wetter and dry regions getting ever drier. Changes in the global water cycle will critically impact environmental, agricultural, and energy systems relied upon by humanity.
However, the relationship between surface salinity patterns in the ocean and changes in the water cycle is puzzling. While the surface salinity pattern has increased by 5-8% since 1950, the water cycle has changed by a smaller amount, 2-3%, over the same period. So what is driving the discrepancy?
Dr Jan Zika (UNSW Sydney) and colleagues at the National Oceanography Centre in the United Kingdom addressed this puzzle using realistic numerical global ocean models. Their results indicate that surface ocean warming is a key and previously overlooked process driving sea surface salinity changes. Warming increases near-surface stratification, which amplifies surface salinity patterns. As a result, approximately half of the observed surface salinity pattern changes can be accounted for by ocean warming, with the remaining changes due to melting ice and changes in the water cycle.
Dr Zika’s research indicates that changes in Earth’s water cycle can be monitored using sea-surface salinity observations, once ocean warming effects are appropriately accounted for.
Citation: Zika, J.D., Skliris, N., Blaker, A.T., Marsh, R., Nurser, A.J.G. and Josey, S.A. . Improved estimates of water cycle change from ocean salinity: the key role of ocean warming. Environmental Research Letters, 13 (7). https://doi.org/10.1088/1748-9326/aace42