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A hybrid A.I. algorithm (data-driven and physically-informed) to estimate river discharges observed by the altimetry satellite SWOT (launch 2021).

For more than a decade, the climate has attracted stochastic dynamists with its unpredictable and complex phenomena. Our attention was attracted by the results of studies on the possibility of oceanic thermohaline circulation failure. We set the task to analyze the stability of the circulation current on-state and to predetermine what extreme events can unbalance it leading to attenuation. We also suggested possible scenarios for the resuscitation of the circulation in the event of its fading.

We used regional climate networks (RCNs) to identify heat waves and droughts in Germany. RCNs provide information for whole areas and provide many details of extreme events. The RCNs were constructed on the grid of the E-Obs data set. Time series correlation was used to construct the networks. Network metrics were compared to standard extreme indices. The results show that RCNs have skill to identify severe and moderate extremes. In average years, distributions resemble Poisson distributions.

In non-equilibrium statistical mechanics, which describes forced-dissipative systems, as air-sea interaction, there is no universal probability density function (pdf). Some such systems have recently been demonstrated to exhibit a symmetry called a fluctuation theorem (FT), which strongly constrains the shape of the pdf. Using satellite data, the mechanical power-input to the ocean by air-sea interaction is questioned to follow or not a FT. A FT is found to apply over specific ocean regions.

Earthquakes have triggered numerous landslides, and much progress has been made in their study. But so far, the dynamics behavior of slope disasters is still lack of understanding, such as “Is there a definite energy and spacial distribution of earthquake-induced landslides? Do giant landslides and small landslides follow different formation mechanisms?”. In this study, we attempts to answer these questions from the point of view of the Self-Organized Critical (SOC) theory.

The paper proposed a theoretical basis that use Gaussian elimination method and special cases of two-variables functions to detect the maxima points by Potential Field Data. Thence, a built computer program to test on models.The obtained results shown that this new approach has more maxima points than the traditional approach. Moreover, the application of new approach to gravitational data in the East Vietnam Sea demonstrated that existent a gravity trench undetectable in the traditional method.

The North Atlantic Oscillation (NAO) phenomenon has a significant impact on the global climate. In this paper, we perform the identification of optimal precursors for NAO to investigate the predictability problem of NAO events. We select proper simulation duration and find out the structure of OPRs for two types of NAO events. Besides, the method applied in this work can be generalized to numerical models that do not have an adjoint model, and its efficiency has been further enhanced.

Turbulent mixing in the ocean interior is mainly contributed by internal wave breaking. Here, the spatially inhomogeneous and seasonally variable diapycnal diffusivities in the upper Philippine Sea were estimated from ARGO float data. The driving processes mainly included the near-inertial waves and internal tides. The mesoscale environment in the Philippine Sea played a significant role in regulating the intensity and shaping the spatial inhomogeneity of the internal tidal mixing.

Earthquake precursor and earthquake monitoring are always important in the earthquake research field, even if there is still debatable about the existence of earthquake precursor. The existence of precursory signal is confirmed by our results. We then attempt to capture and quantitative precursors before rock fracture, by which we establish a link between the rock experiments and natural earthquakes. We try to make a different type of analysis by comparing their similar characteristics.

The influence of quadric shear basic Zonal flows and beta on the downstream development of unstable chaotic baroclinic waves is studied from the two-layer model in wide channel controlled by quasi geostrophic potential vorticity equation. Through the obtained Lorentz equation, we focused on the influence of the quadric shear zonal flow on the downstream development of baroclinic waves, the quadric shear zonal flow has great influence on the stability in space.

Long-lived eddies are an important part of the ocean circulation. Here a dataset for studying eddies in the Gulf of Mexico is created through the analysis of trajectories of drifting instruments. The method involves the identification of quasi-periodic signals, characteristic of particles trapped in eddies, from the displacement records, followed by the creation of a measure of statistical significance. It is expected that this dataset will be of use to other authors studying this region.

We propose an enhanced correlation identification (ECI) algorithm to attenuate the background noise. The cross-correlation matching method is helpful for the extraction of useful components of the raw SSIP data and suppression of background noise. Experiments on both synthetic and real SSIP data show that the ECI algorithm is proposed to preserves the valid information of the raw SSIP data to display the actual location and shape of adjacent high resistivity anomalies.