Article
Geosciences, Multidisciplinary
Ruixiang Zhai, Mahyar Mohtadi, Andrew M. Dolman, Yusuke Yokoyama, Stephan Steinke
Summary: The East Australian Current (EAC) is a western boundary current that plays a significant role in affecting the climate of Australia and New Zealand by transporting warm tropical waters to higher southern latitudes. Recent observations show that the EAC has strengthened due to global warming. However, little is known about the historical variability and forcing mechanisms of the EAC. Using sea surface temperature reconstructions, this study reveals that the EAC has experienced an increase in temperature since 1400 CE, possibly driven by the strengthening of the Southern Hemisphere subtropical gyre circulation and El Nino-Southern Oscillation conditions.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Oceanography
J. U. N. D. E. LI, M. O. N. I. N. Y. A. Roughan
Summary: Examining eddy-mean flow interactions is crucial for understanding mesoscale eddy generation and the role of eddies in large-scale circulation. However, this analysis is lacking in the East Australian Current (EAC) system. This study provides detailed 3D structure and energy budget of eddy-mean flow interactions in the EAC, revealing important patterns and processes.
JOURNAL OF PHYSICAL OCEANOGRAPHY
(2023)
Review
Chemistry, Analytical
Nemesio Fava Sopelsa Neto, Stefano Frizzo Stefenon, Luiz Henrique Meyer, Raul Garcia Ovejero, Valderi Reis Quietinho Leithardt
Summary: This paper proposes a hybrid model for monitoring the electrical power grid by improving existing models using wavelet transform. The results show that using wavelet transform can significantly improve model performance, especially the wavelet ANFIS model.
Article
Chemistry, Multidisciplinary
Pamela M. Barrett, Robin Grun, Michael J. Ellwood
Summary: The study provides data on dissolved and particulate iron concentrations and iron isotope profiles at characteristic study sites within the East Australian Current (EAC). It was found that there are significant inputs of lithogenic particles in the EAC waters, and during southward transit, the mixed layer dFe pools become heavier due to biological uptake.
Article
Geosciences, Multidisciplinary
B. Mourre, A. Santana, A. Bulls, L. Gautreau, M. Licer, A. Jansa, B. Casas, B. Amengual, J. Tintore
Summary: The study investigates the potential of ensemble forecasting for meteotsunami prediction using high-resolution atmospheric and ocean models. Results show a large spread of ensemble simulations in predicting meteotsunami magnitudes, with no preferred set of parameterizations identified. The observed extreme sea-level oscillations lie within the range of the ensemble in 70% of cases, indicating the ensemble approach can provide a realistic range of possibilities for improving meteotsunami predictions.
Article
Green & Sustainable Science & Technology
Marcelo Azevedo Costa, Ramiro Ruiz-Cardenas, Leandro Brioschi Mineti, Marcos Oliveira Prates
Summary: This paper introduces a novel analog-based methodology for multi-step time series forecasting, called dynamic time scan forecasting (DTSF), which combines similarity functions with goodness-of-fit statistics to predict future multi-step data by identifying similar patterns throughout the time series. An ensemble version of the method (eDTSF) achieves competitive results in wind speed time series forecasting, even in situations of high variability, compared to eleven selected concurrent forecasting methods.
Article
Energy & Fuels
Benedikt Schulz, Mehrez El Ayari, Sebastian Lerch, Sandor Baran
Summary: Probabilistic energy forecasting is crucial for integrating volatile power sources like solar energy into the electrical grid. Hybrid models combining physical and statistical methods have shown to be effective, with post-processing models proving to significantly improve the forecast performance of ensemble predictions and correct systematic biases.
Article
Meteorology & Atmospheric Sciences
G. Serazin, A. Di Luca, A. Sen Gupta, M. Roge, N. C. Jourdain, D. Argueso, C. Y. S. Bull
Summary: The study investigates the importance of resolving mesoscale air-sea interactions in representing cyclones impacting the East Coast of Australia. The results show that the intensity of northern ECLs is influenced by thermal feedback and current feedback, but there is no direct link between these feedbacks and changes in ECL properties.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2021)
Article
Environmental Sciences
Lachlan R. Phillips, Neil Malan, Moninya Roughan, Robert Harcourt, Ian Jonsen, Martin Cox, Andrew S. Brierley, David Slip, Adam Wilkins, Gemma Carroll
Summary: This study highlights the significant variability of coastal seascapes along the path of the rapidly intensifying East Australian Current (EAC) Southern Extension in southeast Australia, and emphasizes the critical role of offshore oceanographic processes in driving coastal seascape variability and biological activity.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Oceanography
Juliano D. Ramanantsoa, P. Penven, R. P. Raj, L. Renault, L. Ponsoni, M. Ostrowski, A. F. Dilmahamod, M. Rouault
Summary: The southern extension of the East Madagascar Current (EMC) can be classified into three states: early retroflection, canonical retroflection, and no retroflection. Understanding the influence of current strength and eddies on retroflection formation can help predict marine phenomena in the southern part of Madagascar.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2021)
Article
Environmental Sciences
Junde Li, Moninya Roughan, Colette Kerry, Shivanesh Rao
Summary: Estuarine outflow can significantly impact the coastal ocean's physical and ecological systems. However, due to the dominance of advection in the coastal circulation and low river estuarine outflow, river plumes have been overlooked in southeastern Australia. Therefore, there is a lack of understanding about the spatial and temporal evolution of river plumes during large rainfall events and the interaction between mesoscale circulation and estuarine outflow. This study used a high-resolution hydrodynamic model to simulate idealized plumes from four estuaries and investigate their evolution under different mesoscale circulation scenarios and rainfall events.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Engineering, Marine
Yu Zhan, Huajun Zhang, Jianhao Li, Gen Li
Summary: This study proposes a stacking ensemble learning method to improve the prediction accuracy of wave heights. By analyzing the correlation between wave heights and other oceanic hydrological features, a fusion model consisting of two layers is established. The first layer uses multiple algorithms to determine the deep relations between wave heights and input features, and the second layer uses a linear regression model to fit the relation between the first layer outputs and actual wave heights. Experimental results show that the fusion model outperforms the four individual models.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Oceanography
Xiaoyu Long, Matthew J. Widlansky, Claire M. Spillman, Arun Kumar, Magdalena Balmaseda, Philip R. Thompson, Yoshimitsu Chikamoto, Grant A. Smith, Bohua Huang, Chul-Su Shin, Mark A. Merrifield, William V. Sweet, Eric Leuliette, H. S. Annamalai, John J. Marra, Gary Mitchum
Summary: Coastal high water level events are on the rise due to global sea-level rise, but operational seasonal forecasts of sea-level anomalies are lacking in most coastal regions. Advances in forecasting climate variability using coupled ocean-atmosphere global models provide the opportunity to predict future high water events several months in advance. Multi-model assessments show that skillful seasonal sea-level forecasts are possible in many, but not all, parts of the global ocean.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2021)
Article
Environmental Sciences
Jia Liu, Shaojun Zheng, Ming Feng, Lingling Xie, Baoxin Feng, Peng Liang, Lei Wang, Lina Yang, Li Yan
Summary: The seasonal variability of EKE in the East Australian Current (EAC) region, a western boundary current of the South Pacific subtropical Circulation, is studied using satellite altimeter observations and ocean models. High EKE is concentrated in the shear-region between the poleward EAC southern extension and the equatorward EAC recirculation, with obvious seasonal variation. The mixed instabilities within the upper ocean, consisting of both barotropic and baroclinic instabilities, modulate the seasonal variability of EKE.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Environmental Sciences
Lei Xu, Hongchu Yu, Zeqiang Chen, Wenying Du, Nengcheng Chen, Chong Zhang
Summary: Ocean primary productivity is crucial for ocean ecosystems and the carbon cycle. Accurate forecasting of ocean primary productivity months in advance is beneficial for marine management. This study proposes a joint forecasting model that combines seasonal climate predictions and temporal memories of relevant factors to examine the predictability of ocean productivity. The results show that the combination of seasonal SST predictions and local memory can skillfully predict a large portion of productive oceans at different lead times. The hybrid data-driven and model-driven approach improves the predictability of ocean productivity, with seasonal climate predictions playing a significant role.
Review
Geochemistry & Geophysics
Gregory C. Johnson, Shigeki Hosoda, Steven R. Jayne, Peter R. Oke, Stephen C. Riser, Dean Roemmich, Tohsio Suga, Virginie Thierry, Susan E. Wijffels, Jianping Xu
Summary: Argo, an international network of nearly 4,000 autonomous robotic profiling floats, has revolutionized physical oceanography. After two decades, Argo data have supported thousands of scientific publications and improved real-time forecasts and projections.
ANNUAL REVIEW OF MARINE SCIENCE
(2022)
Article
Computer Science, Interdisciplinary Applications
Mabel Calim Costa, Paulo Nobre, Peter Oke, Andreas Schiller, Leo San Pedro Siqueira, Guilherme Pimenta Castela
Summary: The Spectral Diagram (SD) is a new tool for comparing time series in the frequency domain, displaying coherence function, power, amplitude, phase, and skill score. Through sea-level comparisons, the SD demonstrates the impact of adjusting phase information in models and improving estimates.
COMPUTERS & GEOSCIENCES
(2022)
Article
Meteorology & Atmospheric Sciences
Leon Hermanson, Doug Smith, Melissa Seabrook, Roberto Bilbao, Francisco Doblas-Reyes, Etienne Tourigny, Vladimir Lapin, Viatcheslav V. Kharin, William J. Merryfield, Reinel Sospedra-Alfonso, Panos Athanasiadis, Dario Nicoli, Silvio Gualdi, Nick Dunstone, Rosie Eade, Adam Scaife, Mark Collier, Terence O'Kane, Vassili Kitsios, Paul Sandery, Klaus Pankatz, Barbara Frueh, Holger Pohlmann, Wolfgang Mueller, Takahito Kataoka, Hiroaki Tatebe, Masayoshi Ishii, Yukiko Imada, Tim Kruschke, Torben Koenigk, Mehdi Pasha Karami, Shuting Yang, Tian Tian, Liping Zhang, Tom Delworth, Xiaosong Yang, Fanrong Zeng, Yiguo Wang, Francois Counillon, Noel Keenlyside, Ingo Bethke, Judith Lean, Juerg Luterbacher, Rupa Kumar Kolli, Arun Kumar
Summary: As climate change accelerates, societies and climate-sensitive socioeconomic sectors need new methods to guide future adaptation efforts. Operational decadal predictions, like the ones provided by the WMO Lead Centre for Annual to Decadal Climate Predictions, can fill the gap between seasonal forecasts and climate projections. The collaboration produces skillful predictions that inform policy-makers about global climate trends and the probability of exceeding the Paris Agreement's temperature targets.
BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY
(2022)
Article
Meteorology & Atmospheric Sciences
Serena Schroeter, Paul A. Sandery
Summary: This study investigates the sensitivity of simulated Antarctic sea ice to parameter variation using a global coupled climate model. The results show that changes in certain parameters can significantly impact the areal coverage, thickness, and seasonality of sea ice, with the sea ice turning angle parameter having the largest effect. Additionally, the study finds that setting the snow and ice albedo above the default value increases mean sea ice year-round, while low values of heat exchange between the ocean and base of the sea ice reduce bottom melt and slow sea ice retreat.
Article
Engineering, Ocean
N. V. Zilberman, M. Scanderbeg, A. R. Gray, P. R. Oke
Summary: This study aims to provide observation-based estimates of large-scale subsurface ocean circulation. By exploiting the drift of autonomous profiling floats, the inferred circulation at the parking depth is carefully isolated and combined with observations from over 11,000 floats to deliver a new dataset with unprecedented accuracy. The new estimates of subsurface currents are suitable for assessing global models, reanalyses, and forecasts, as well as constraining ocean circulation in data-assimilating models.
JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY
(2023)
Article
Meteorology & Atmospheric Sciences
Terence j. O'kane, R. U. S. S. E. L. L. Fiedler, Mark a. Collier, V. A. S. S. I. L. I. Kitsios
Summary: Recent studies have found that climate and atmospheric models respond differently to various stochastic forcing and subgrid-scale parameterization schemes. While stochastic parameterization of ocean eddies is an active area, it has mainly been applied to idealized models, with few studies on ocean general circulation models. This study examines the sensitivity of a low-resolution climate model to stochastic forcing of momentum fluxes in regions of high variability in a three-dimensional ocean model configuration. The results show that increased stochastic forcing leads to enhanced conversion of transient to seasonal potential energy, as well as a redistribution from seasonal to small-scale transient kinetic energy. However, strong stochastic forcing, especially in the tropics, can cause undesirable changes to the ocean steady state. Therefore, careful selection of the magnitude and spatial extent of stochastic forcing is necessary to achieve desirable results. These findings highlight the importance of comprehensive evaluation of ocean model responses to stochastic parameterizations.
JOURNAL OF CLIMATE
(2023)
Article
Multidisciplinary Sciences
Illia Horenko, Edoardo Vecchi, Juraj Kardos, Andreas Waechter, Olaf Schenk, Terence O'Kane, Patrick Gagliardini, Susanne Gerber
Summary: Regression learning is a long-standing problem in statistics, machine learning, and deep learning. This study proposes a simplification of this problem by incorporating the physical principle of entropy maximization, leading to a computationally cheap and robust algorithm called SPARTAn. SPARTAn outperforms existing learning tools in terms of predictive power, sparsity, and interpretability, and reveals the important role of ocean temperature variability in interannual climate predictions.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Editorial Material
Meteorology & Atmospheric Sciences
Christian L. E. Franzke, June-Yi Lee, Terence O'Kane, William Merryfield, Xuebin Zhang
ASIA-PACIFIC JOURNAL OF ATMOSPHERIC SCIENCES
(2023)
Article
Meteorology & Atmospheric Sciences
V. Kitsios, J. S. Frederiksen, T. J. O'Kane
Summary: Ocean circulation dynamics is a complex system with various interactions between different scales and components, which can be effectively represented and simulated using numerical models. The accuracy of these simulations depends on proper parameterizations, especially for the subgrid interactions. In this study, parameterizations for different classes of subgrid interactions are developed and validated in idealized Antarctic Circumpolar Current flows.
JOURNAL OF ADVANCES IN MODELING EARTH SYSTEMS
(2023)
Article
Environmental Sciences
Jorgen S. Frederiksen, Terence J. O'Kane
Summary: A realizable EDMAC is proposed for the interaction of two-dimensional turbulence and transient waves, guaranteeing computational efficiency and realizability in the presence of transient waves. The important contributions made by Jack Herring in laying the foundations of statistical dynamical closure theories of fluid turbulence are briefly reviewed, and related developments and impacts are discussed. The relationships between theoretical approaches in statistical classical and quantum field theories are outlined, and the advancements in fluid turbulence theory are compared to those in strong interaction quantum field theory.
Article
Environmental Sciences
Vassili Kitsios, Terence John O'Kane, David Newth
Summary: Machine learning techniques can simulate climate model outputs at a fraction of the computational cost, facilitating rapid and efficient assessment of future climate responses to a wide range of carbon emissions scenarios and decarbonisation trajectories.
COMMUNICATIONS EARTH & ENVIRONMENT
(2023)
Article
Geography, Physical
Serena Schroeter, Terence J. O'Kane, Paul A. Sandery
Summary: Across the long-term satellite record of about 43 years, there has been a small overall increase in Antarctic sea ice extent due to opposing regional sea ice concentration anomalies. The long-term trend pattern is mainly influenced by the earliest years of the satellite record, while compensating regional anomalies diminish over time. Recent trends show a reversal of the regional pattern of sea ice behavior, with some regions abruptly shifting in line with recent anomalous sea ice behavior, while other regions exhibit a steady change predating these anomalies. The shifting trend patterns in many regions coincide with enhanced north-south flow and the increasingly wave-3-like structure of the Southern Annular Mode.
Article
Physics, Fluids & Plasmas
Jorgen S. Frederiksen, Terence J. O'Kane
Summary: This study formulates abridged statistical dynamical closures for the interaction of two-dimensional inhomogeneous turbulent flows with topography and Rossby waves. The closures are based on the Quasi-diagonal Direct Interaction Approximation (QDIA) theory and have been shown to be efficient and accurate in predicting statistical properties. A new closure model, Eddy Damped Markovian Inhomogeneous Closure (EDMIC), which generalizes the Eddy Dampened Quasi Normal Markovian (EDQNM) to inhomogeneous flows, is also proposed.
Article
Meteorology & Atmospheric Sciences
Mark A. Collier, Terence J. O'Kane, Vassili Kitsios, Paul A. Sandery
Summary: The CAFE-60 system, developed by the CSIRO Climate Science Centre, provides ensemble forecasts of the near-term climate. It meets the requirements to become a World Meteorological Organization Global Data Producing Centre and has provided output in the UK Met Office international data exchange.
JOURNAL OF SOUTHERN HEMISPHERE EARTH SYSTEMS SCIENCE
(2022)
Review
Meteorology & Atmospheric Sciences
Wei Zhang, Yu Sun, Yapeng Wu, Junyu Dong, Xiaojiang Song, Zhiyi Gao, Renbo Pang, Boyu Guoan
Summary: This study employed a spatiotemporal deep-learning method to correct biases in numerical ocean wave forecasts. By using a correction model driven by both wave and wind fields and a novel pixel-switch loss function, the corrected results performed well in different seasons and improved the accuracy of the original forecasts.