Indian Ocean
A Survey of Event Causality Identification: Principles, Taxonomy, Challenges, and Assessment
Cheng, Qing, Zeng, Zefan, Hu, Xingchen, Si, Yuehang, Liu, Zhong
Event Causality Identification (ECI) has become a crucial task in Natural Language Processing (NLP), aimed at automatically extracting causalities from textual data. In this survey, we systematically address the foundational principles, technical frameworks, and challenges of ECI, offering a comprehensive taxonomy to categorize and clarify current research methodologies, as well as a quantitative assessment of existing models. We first establish a conceptual framework for ECI, outlining key definitions, problem formulations, and evaluation standards. Our taxonomy classifies ECI methods according to the two primary tasks of sentence-level (SECI) and document-level (DECI) event causality identification. For SECI, we examine feature pattern-based matching, deep semantic encoding, causal knowledge pre-training and prompt-based fine-tuning, and external knowledge enhancement methods. For DECI, we highlight approaches focused on event graph reasoning and prompt-based techniques to address the complexity of cross-sentence causal inference. Additionally, we analyze the strengths, limitations, and open challenges of each approach. We further conduct an extensive quantitative evaluation of various ECI methods on two benchmark datasets. Finally, we explore future research directions, highlighting promising pathways to overcome current limitations and broaden ECI applications.
Regional Ocean Forecasting with Hierarchical Graph Neural Networks
Holmberg, Daniel, Clementi, Emanuela, Roos, Teemu
Accurate ocean forecasting systems are vital for understanding marine dynamics, which play a crucial role in environmental management and climate adaptation strategies. Traditional numerical solvers, while effective, are computationally expensive and time-consuming. Recent advancements in machine learning have revolutionized weather forecasting, offering fast and energy-efficient alternatives. Building on these advancements, we introduce SeaCast, a neural network designed for high-resolution, medium-range ocean forecasting. SeaCast employs a graph-based framework to effectively handle the complex geometry of ocean grids and integrates external forcing data tailored to the regional ocean context. Our approach is validated through experiments at a high spatial resolution using the operational numerical model of the Mediterranean Sea provided by the Copernicus Marine Service, along with both numerical and data-driven atmospheric forcings.
Advancing Marine Heatwave Forecasts: An Integrated Deep Learning Approach
Ning, Ding, Vetrova, Varvara, Koh, Yun Sing, Bryan, Karin R.
Marine heatwaves (MHWs), an extreme climate phenomenon, pose significant challenges to marine ecosystems and industries, with their frequency and intensity increasing due to climate change. This study introduces an integrated deep learning approach to forecast short-to-long-term MHWs on a global scale. The approach combines graph representation for modeling spatial properties in climate data, imbalanced regression to handle skewed data distributions, and temporal diffusion to enhance forecast accuracy across various lead times. To the best of our knowledge, this is the first study that synthesizes three spatiotemporal anomaly methodologies to predict MHWs. Additionally, we introduce a method for constructing graphs that avoids isolated nodes and provide a new publicly available sea surface temperature anomaly graph dataset. We examine the trade-offs in the selection of loss functions and evaluation metrics for MHWs. We analyze spatial patterns in global MHW predictability by focusing on historical hotspots, and our approach demonstrates better performance compared to traditional numerical models in regions such as the middle south Pacific, equatorial Atlantic near Africa, south Atlantic, and high-latitude Indian Ocean. We highlight the potential of temporal diffusion to replace the conventional sliding window approach for long-term forecasts, achieving improved prediction up to six months in advance. These insights not only establish benchmarks for machine learning applications in MHW forecasting but also enhance understanding of general climate forecasting methodologies.
FengWu-W2S: A deep learning model for seamless weather-to-subseasonal forecast of global atmosphere
Ling, Fenghua, Chen, Kang, Wu, Jiye, Han, Tao, Luo, Jing-Jia, Ouyang, Wanli, Bai, Lei
Seamless forecasting that produces warning information at continuum timescales based on only one system is a long-standing pursuit for weather-climate service. While the rapid advancement of deep learning has induced revolutionary changes in classical forecasting field, current efforts are still focused on building separate AI models for weather and climate forecasts. To explore the seamless forecasting ability based on one AI model, we propose FengWu-Weather to Subseasonal (FengWu-W2S), which builds on the FengWu global weather forecast model and incorporates an ocean-atmosphere-land coupling structure along with a diverse perturbation strategy. FengWu-W2S can generate 6-hourly atmosphere forecasts extending up to 42 days through an autoregressive and seamless manner. Our hindcast results demonstrate that FengWu-W2S reliably predicts atmospheric conditions out to 3-6 weeks ahead, enhancing predictive capabilities for global surface air temperature, precipitation, geopotential height and intraseasonal signals such as the Madden-Julian Oscillation (MJO) and North Atlantic Oscillation (NAO). Moreover, our ablation experiments on forecast error growth from daily to seasonal timescales reveal potential pathways for developing AI-based integrated system for seamless weather-climate forecasting in the future.
Identifying Key Drivers of Heatwaves: A Novel Spatio-Temporal Framework for Extreme Event Detection
Pérez-Aracil, J., Peláez-Rodríguez, C., McAdam, Ronan, Squintu, Antonello, Marina, Cosmin M., Lorente-Ramos, Eugenio, Luther, Niklas, Torralba, Veronica, Scoccimarro, Enrico, Cavicchia, Leone, Giuliani, Matteo, Zorita, Eduardo, Hansen, Felicitas, Barriopedro, David, Garcia-Herrera, Ricardo, Gutiérrez, Pedro A., Luterbacher, Jürg, Xoplaki, Elena, Castelletti, Andrea, Salcedo-Sanz, S.
Heatwaves (HWs) are extreme atmospheric events that produce significant societal and environmental impacts. Predicting these extreme events remains challenging, as their complex interactions with large-scale atmospheric and climatic variables are difficult to capture with traditional statistical and dynamical models. This work presents a general method for driver identification in extreme climate events. A novel framework (STCO-FS) is proposed to identify key immediate (short-term) HW drivers by combining clustering algorithms with an ensemble evolutionary algorithm. The framework analyzes spatio-temporal data, reduces dimensionality by grouping similar geographical nodes for each variable, and develops driver selection in spatial and temporal domains, identifying the best time lags between predictive variables and HW occurrences. The proposed method has been applied to analyze HWs in the Adda river basin in Italy. The approach effectively identifies significant variables influencing HWs in this region. This research can potentially enhance our understanding of HW drivers and predictability.
Jal Anveshak: Prediction of fishing zones using fine-tuned LlaMa 2
Mejari, Arnav, Vaghulade, Maitreya, Chitaliya, Paarshva, Telang, Arya, D'mello, Lynette
In recent years, the global and Indian government efforts in monitoring and collecting data related to the fisheries industry have witnessed significant advancements. Despite this wealth of data, there exists an untapped potential for leveraging artificial intelligence based technological systems to benefit Indian fishermen in coastal areas. To fill this void in the Indian technology ecosystem, the authors introduce Jal Anveshak. This is an application framework written in Dart and Flutter that uses a Llama 2 based Large Language Model fine-tuned on pre-processed and augmented government data related to fishing yield and availability. Its main purpose is to help Indian fishermen safely get the maximum yield of fish from coastal areas and to resolve their fishing related queries in multilingual and multimodal ways.
Houthis launch missile, drone attacks on US warships off Yemen's coast
US warships came under sustained missile and drone attack from Houthi fighters as they sailed off the coast of Yemen, the Pentagon has confirmed, with the armed group claiming it attacked the US aircraft carrier Abraham Lincoln and two US destroyers. Pentagon spokesperson Air Force Major General Patrick Ryder said on Tuesday that the United States military's Central Command (CENTCOM) forces "successfully repelled multiple Iranian backed Houthi attacks during a transit of the Bab al-Mandeb strait", which connects the Red Sea to the Gulf of Aden. Ryder told reporters at a news conference that two US-guided missile destroyers – the USS Stockdale and USS Spruance – were attacked by at least eight one-way attack drones, five antiship ballistic missiles and three antiship cruise missiles. All the Houthi drones and missiles "were successfully engaged and defeated", and neither of the US Navy ships were damaged or personnel hurt, he said. Ryder added that he was not aware of any attacks against the aircraft carrier USS Abraham Lincoln.
Sunken WWII US destroyer, known as 'Dancing Mouse,' discovered 80 years after battle with Japanese
The wreckage of the USS Edsall, an American warship that was sunk during a battle with Japanese forces in World War II, has been discovered more than 80 years after it was lost at the bottom of the sea, U.S. and Australian officials announced Monday. The final resting place of the USS Edsall, a Clemson-class destroyer, was discovered late last year at the bottom of the Indian Ocean, according to the U.S. Navy and Royal Australian Navy. "Working in collaboration with the U.S. Navy, the Royal Australian Navy used advanced robotic and autonomous systems, normally used for hydrographic survey capabilities, to locate USS Edsall on the sea-bed," Chief of Royal Australian Navy, Vice Admiral Mark Hammond, said in a statement. The warship was sunk on March 1, 1942, three months after the attack on Pearl Harbor, during an encounter with Japanese battleships and dive bombers. The USS Edsall was a Clemson-class destroyer, measuring 314 feet in length and capable of 35 knots.
Mauritius election: Amid wiretapping scandal, what's at stake?
Some one million eligible voters in the Indian Ocean Mauritius will head out to vote on Sunday amid an explosive scandal that has implicated government figures in a covert wiretapping operation. Since independence from Britain in 1968, the southeast African country has maintained a strong, vibrant parliamentary democracy. This will be its 12th national election. Elections are usually deemed free and fair and turnout is normally high, at close to 80 percent. This time, however, the unusual drama caused by the leaked recordings has sparked national agitation and dominated the campaign season.
Discovering Latent Structural Causal Models from Spatio-Temporal Data
Wang, Kun, Varambally, Sumanth, Watson-Parris, Duncan, Ma, Yi-An, Yu, Rose
Many important phenomena in scientific fields such as climate, neuroscience, and epidemiology are naturally represented as spatiotemporal gridded data with complex interactions. For example, in climate science, researchers aim to uncover how large-scale events, such as the North Atlantic Oscillation (NAO) and the Antarctic Oscillation (AAO), influence other global processes. Inferring causal relationships from these data is a challenging problem compounded by the high dimensionality of such data and the correlations between spatially proximate points. We present SPACY (SPAtiotemporal Causal discoverY), a novel framework based on variational inference, designed to explicitly model latent time-series and their causal relationships from spatially confined modes in the data. Our method uses an end-to-end training process that maximizes an evidence-lower bound (ELBO) for the data likelihood. Theoretically, we show that, under some conditions, the latent variables are identifiable up to transformation by an invertible matrix. Empirically, we show that SPACY outperforms state-of-the-art baselines on synthetic data, remains scalable for large grids, and identifies key known phenomena from real-world climate data.