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Atmospheric and Oceanic Science Letters 2025年第1期18卷 24-31页

作者： Tiantian Tang Jiaying He Huihang Sun Jingjia Luo Institute for climate and Application research(ICAR)/Key Laboratory of Meteorological Disaster Nanjing University of Information Science and TechnologyNanjingChina

A remarkable marine heatwave,known as the“Blob”,occurred in the Northeast Pacific Ocean from late 2013 to early 2016,which displayed strong warm anomalies extending from the surface to a depth of 300 *** study employed two assimilation schemes based on the global climate Forecast System of Nanjing University of Information Science(NUIST-CFS 1.0)to investigate the impact of ocean data assimilation on the seasonal prediction of this extreme marine *** sea surface temperature(SST)nudging scheme assimilates SST only,while the deterministic ensemble Kalman filter(EnKF)scheme assimilates observations from the surface to the deep *** latter notably improves the forecasting skill for subsurface temperature anomalies,especially at the depth of 100-300 m(the lower layer),outperforming the SST nudging *** excels in predicting both horizontal and vertical heat transport in the lower layer,contributing to improved forecasts of the lower-layer warming during the *** improvements stem from the assimilation of subsurface observational data,which are important in predicting the upper-ocean *** results suggest that assimilating ocean data with the EnKF scheme significantly enhances the accuracy in predicting subsurface temperature anomalies during the Blob and offers better understanding of its underlying mechanisms.

关键词： Seasonal forecast Ocean data assimilation Marine heatwave Subsurface temperature

Risk,Rationality,and Resilience

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International Journal of Disaster Risk Science 2010年第1期1卷 10-16页

作者： Carlo Jaeger potsdam Institute for climate impact research(PIK) 14473 PotsdamGermany

Improving our ability to cope with large risks is one of the key challenges for humankind in this century. This article outlines a research program in this perspective. Starting with a concrete example of a relatively small disaster, it questions simplistic ideas of rationality. It then proposes a fresh look at the concepts of probability and utility in the context of socioecological systems. This leads first to an emphasis on the problem of equilibrium selection, and then to a distinction between three kinds of resilience that matter both for theory and practice of risk management. They can be investigated by paying attention to the transitions into and out of actual disasters.

关键词： Resilience management. disaster

Avoiding the Avoidable:Towards a European Heat Waves Risk Governance

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International Journal of Disaster Risk Science 2011年第1期2卷 1-14页

作者： Wiebke Lass Armin Haas Jochen Hinkel Carlo Jaeger potsdam Institute for climate impact research(PIK) D-14412 PotsdamGermany

The death toll of recent heat waves in developed countries has been remarkably high, contradicting the common assumption that high levels of economic and technological development automatically lead to lower vulnerability to weather extremes. Future climate change may further increase this vulnerability. In this article we examine some recent evidence of heat wave-related mortality and we conclude that while economic wealth and technological capacity might be a necessary condition for adequately coping with adverse climate change effects, they are not sufficient. Questions of awareness, preparedness, organizational issues, and actor networks have to be addressed in a proactive and focused manner in order to avoid future heat wave damages. We propose some practical consequences for heat wave adaptation measures by adopting a risk governance framework that can be universally applied, as it is sufficiently flexible to deal with the multi-level and often fragmented reality of existing coping measures.

关键词： weather wave consequences

A threefold approach to rescue the 2030 Agenda from failing

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National Science Review 2023年第7期10卷 13-15页

作者： Prajal Pradhan Bauhaus Earth GmbH potsdam Institute for climate impact research (PIK) Member of the Leibniz Association

Countries are not on track to meet the2030 Agenda for Sustainable Development [1] that calls for transformative changes to shift the world onto a sustainable and resilient *** 2030Agenda comprises 17 Sustainable Development Goals (SDGs) and 169 targets to be achieved by 2030,balancing the three sustainability dimensions—social,economic,and *** far,SDGs have had a limited transforma-tive impact [2] because of their selective implementation without considering their complex *** interact positively (***) or negatively(***-offs) depending on contextand location-specific *** to meet SDGs will negatively affect the lives of billions of people and worsen socioeconomic and environmental crises.

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Sensitivity of the Indian Monsoon to Human Activities

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Advances in Atmospheric Sciences 2008年第6期25卷 932-945页

作者： B. KNOPF K. ZICKFELD M. FLECHSIG V. PETOUKHOV potsdam Institute for climate impact research (PIK) School of Earth and Ocean Sciences University of Victoria

In this paper the authors perform an extensive sensitivity analysis of the Indian summer monsoon rainfall to changes in parameters and boundary conditions which are influenced by human activities. For this study the authors use a box model of the Indian monsoon which reproduces key features of the observed monsoon dynamics such as the annual course of precipitation and the transitions between winter and summer regimes. Because of its transparency and computational efficiency, this model is highly suitable for exploring the effects of anthropogenic perturbations such as emissions of greenhouse gases and sulfur dioxide, and land cover changes, on the Indian monsoon. Results of a systematic sensitivity analysis indicate that changes in those parameters which are related to emissions of greenhouse gases lead to an increase in Indian summer rainfall. In contrast, all parameters related to higher atmospheric aerosol concentrations lead to a decrease in Indian rainfall. Similarly, changes in parameters which can be related to forest conversion or desertifieation, act to decrease the summer precipitation. The results indicate that the sign of precipitation changes over India will be dependent on the direction and relative magnitude of different human perturbations.

关键词： Indian monsoon sensitivity analysis global change anthropogenic climate change

Impulsive control of chaotic systems and its applications in synchronization

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Chinese Physics B 2011年第5期20卷 184-190页

作者：吴波刘洋卢剑权 College of Mathematics Physics and Information EngineeringZhejiang Normal University Department of Mathematics Southeast University potsdam Institute for climate impact research TelegraphenbergD-14415 PotsdamGermany

In this paper, some novel sufficient conditions for asymptotic stability of impulsive control systems are presented by comparison systems. The results are used to obtain the conditions under which the chaotic systems can be asymptotically controlled to the origin via impulsive control. Compared with some existing results, our results are more relaxed in the sense that the Lyapunov function is required to be nonincreasing only along a subsequence of switchings. Moreover, a larger upper bound of impulsive intervals for stabilization and synchronization is obtained.

关键词： comparison systems impulsive control chaotic systems synchronization

Nonsingularity of Grain-like cascade FSRs via semi-tensor product

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Science China(Information Sciences) 2018年第1期61卷 58-69页

作者： Jianquan LU Meilin LI Yang LIU Daniel W.C.HO Jrgen KURTHS School of Mathematics Southeast University College of Mathematics Physics and Information Engineering Zhejiang Normal University Department of Mathematics City University of Hong Kong potsdam Institute for climate impact research

In this paper, Grain-like cascade feedback shift registers(FSRs) are regarded as two Boolean networks(BNs), and the semi-tensor product(STP) of the matrices is used to convert the Grain-like cascade FSRs into an equivalent linear equation. Based on the STP, a novel method is proposed herein to investigate the nonsingularity of Grain-like cascade FSRs. First, we investigate the property of the state transition matrix of Grain-like cascade FSRs. We then propose their sufficient and necessary nonsingularity condition. Next,we regard the Grain-like cascade FSRs as Boolean control networks(BCNs) and further provide a sufficient condition of their nonsingularity. Finally, two examples are provided to illustrate the results obtained in this paper.

关键词： Grain-like cascade FSRs Boolean control networks Boolean networks semi-tensor product nonsingularity

Rate-dependent tipping-delay phenomenon in a thermoacoustic system with colored noise

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Science China(Technological Sciences) 2020年第11期63卷 2315-2327页

作者： ZHANG XiaoYu XU Yong LIU Qi KURTHS Jurgen Department of Applied Mathematics Northwestern Polytechnical UniversityXi’an 710072China MIIT Key Laboratory of Dynamics and Control of Complex Systems Northwestern Polytechnical UniversityXi’an 710072China potsdam Institute for climate impact research Potsdam 14412Germany

Tipping is a phenomenon in multistable systems where small changes in inputs cause huge changes in *** the parameter varies within a certain time scale,the rate will affect the tipping *** behaviors are undesirable in thermoacoustic systems,which are widely used in aviation,power generation and other ***,this paper aims at considering the tipping behaviors of the thermoacoustic system with the time-varying parameters and the combined excitations of additive and multiplicative colored *** dynamical behaviors for the proposed thermoacoustic model are implemented through the reduced Fokker-Planck-Kolmogorov equation derived by a standard stochastic averaging ***,the tipping problems of the rate-dependent thermoacoustic systems with random fluctuations are studied by virtue of the obtained probability density *** results show that the rate delays the value of the tipping parameter compared to the one with the quasi-steady assumption,which is called as a rate-dependent tipping-delay ***,the influences of the initial values,the rate,the changing time of the parameters,and the correlation time of the noises on the rate-dependent tipping-delay phenomenon are analyzed in *** results are of great significance for research in related fields such as aviation and land gas turbines.

关键词： thermoacoustic system colored noise rate-dependent tipping-delay phenomenon stochastic averaging method

ResoNet:Robust and Explainable ENSO Forecasts with Hybrid Convolution and Transformer Networks

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Advances in Atmospheric Sciences 2024年第7期41卷 1289-1298页

作者： Pumeng LYU Tao TANG Fenghua LING Jing-Jia LUO Niklas BOERS Wanli OUYANG Lei BAI Shanghai Artificial Intelligence Laboratory Shanghai 200072China Zhejiang Meteorological Observatory Hangzhou 310002China Institute for climate and Application research(ICAR) Nanjing University of Information Science and TechnologyNanjing 210044China Technical University of Munich Potsdam Institute for Climate Impact ResearchPotsdam 14473Germany

Recent studies have shown that deep learning(DL)models can skillfully forecast El Niño–Southern Oscillation(ENSO)events more than 1.5 years in ***,concerns regarding the reliability of predictions made by DL methods persist,including potential overfitting issues and lack of ***,we propose ResoNet,a DL model that combines CNN(convolutional neural network)and transformer *** hybrid architecture enables our model to adequately capture local sea surface temperature anomalies as well as long-range inter-basin interactions across *** show that ResoNet can robustly predict ENSO at lead times of 19 months,thus outperforming existing approaches in terms of the forecast *** to an explainability method applied to ResoNet predictions of El Niño and La Niña from 1-to 18-month leads,we find that it predicts the Niño-3.4 index based on multiple physically reasonable mechanisms,such as the recharge oscillator concept,seasonal footprint mechanism,and Indian Ocean capacitor ***,we demonstrate for the first time that the asymmetry between El Niño and La Niña development can be captured by *** results could help to alleviate skepticism about applying DL models for ENSO prediction and encourage more attempts to discover and predict climate phenomena using AI methods.

关键词： deep learning ENSO CNN transformer

Probabilistic description of extreme oscillations and reliability analysis in rolling motion under stochastic excitation

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Science China(Technological Sciences) 2023年第9期66卷 2586-2596页

作者： ZHAO Dan LI YongGe XU Yong LIU Qi KURTHS Jürgen School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an 710072China MOE Key Laboratory for Complexity Science in Aerospace Northwestern Polytechnical UniversityXi’an 710072China potsdam Institute for climate impact research Potsdam 14412Germany Department of Physics Humboldt University BerlinBerlin 12489Germany

Large-amplitude rolling motions, also regarded as extreme oscillations, are a great threat to marine navigation, which may lead to capsizing in ship motion. Therefore, it is important to quantify extreme oscillations, assess reliability of ship systems, and establish a suitable indicator to characterize extreme oscillations in ship systems. In this work, extreme events are investigated in a ship model considering a complex ocean environment, described by a single-degree-of-freedom nonlinear system with stochastic harmonic excitation and colored Gaussian noise. The stationary probability density function(PDF) of the system is derived through a probabilistic decomposition-synthesis method. Based on this, we infer the classical damage rate of the system. Furthermore, a new indicator, independent of the PDF, is proposed to quantify the damage related only to the fourth-order moment of the system and the threshold for extreme events. It is more universal and easier to determine as compared with the classical damage rate. A large damping ratio, a large noise intensity, or a short correlation time can reduce the damage rate and the value of the *** findings provide new insights and theoretical guidance to avoid extreme oscillations and assess the reliability of practical ship movements.

关键词： rolling motion colored noise extreme oscillations reliability probabilistic decomposition-synthesis method

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