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1

The hydrological impact of tropical cyclones on soil moisture using a sensor based hybrid deep learning model

Srivastava Gautam, Kavitha V., Vimaladevi M., Parthiban N.

Acta Geophysica

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2022

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Vol. 70, no 6

2933--2951

EN

Tropical cyclones that originate from the Indian Ocean affect the Indian Sub-Continent. Heavy rainfall and flooding occur because of these cyclones. South Odisha was affected by Cyclonic Storm Daye in September 2018 and Cyclonic Storm Titli was occurred in August affecting Andhra Pradesh and Odisha as well. The Eastern portion of India was affected by the Cyclonic Storm Fani in April 2019. In May 2020, West Bengal was affected by the Amphan which is a Super Cyclonic Storm and in the same year Tamil Nadu was affected by the very severe Cyclonic Storm Nivar in November 2020. These are just a few of the notable cyclonic events in the Indian Sub-Continent. These cyclonic events cause a dramatic change in a very short time from dry soil to exceptional flooding. In this proposed work, we are attempting to create an observations-driven prediction model to quantify the soil moisture variations daily, predict county-based meteorology and evaluate the cause of cyclones and heavy rainfall in certain areas of India. In our work, we applied a deep learning-based methodology to predict soil moisture. For the prediction model, we fused Feed Forward Neural Networks with the Gated Recurrent Unit (GRU) model and present the prediction results. We have used climatic as well as environmental data published by the Indian Meteorological Department (IMD) Warning from 2011. The collected data is time-series data. Comparisons and the relationship that exists between soil moisture and meteorological data are made and analyzed. The soil moisture of the South Indian states Karnataka, Andhra Pradesh and Tamil Nadu are predicted from weather data using a hybrid deep learning model. The evaluations of the proposed work using Mean Absolute Error (MAE), Mean Squared Error (MSE), Root Mean Squared Error (RMSE) and R-squared (R2 ) against Non-hybrid Neural Network models such as Artificial Neural Networks (ANN), Convolutional Neural Networks, and Gated Recurrent Unit (GRU) models is analyzes where our model has given better results.

2

The response of cyclonic eddies to typhoons based on satellite remote sensing data for 2001-2014 from the South China Sea

Yu Fangjie, Yang Qiongqiong, Chen Ge, Li Qiuxiang

Oceanologia

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2019

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No. 61 (2)

265--275

EN

Eddies are known to be affected by typhoons, and in recent years, the general three-dimensional structure, as well as features of the spatial and temporal distributions of eddies have been determined. However, the type of eddy that is most likely to be affected by a typhoon remains unclear. In this paper, quantitative and qualitative methods were used to study the eddies that are most sensitive to upper-ocean tropical cyclones (TCs) from the perspective of eddy characteristics, and the quantitative results showed that not all eddies were enhanced under the influence of typhoons. Enhancement of the eddy amplitude (Amp), radius (Rad), area (A), or eddy kinetic energy (EKE) accounted for 92.3% of the total eddy within the radius of the typhoon. Qualitative analyses showed the following: First, eddies located on different sides of the typhoon tracks were differently affected, as eddies on the left side were more intensely affected by the typhoon than eddies on the right side, and second, eddies with short lifespans or small radii were more susceptible to the TCs.

3

Tropical cyclones avoidance in ocean navigation - safety of navigation and some economical aspects

Szymański M., Wiśniewski B.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2018

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Vol. 12, no. 1

57--68

EN

Based upon the true voyages various methods of avoidance maneuver determination in ship - cyclone encounter situations were presented. The goal was to find the economically optimal solution (minimum fuel consumption, maintaining the voyage schedule) while at the same time not to exceed an acceptable weather risk level.

4

A South Pacific Cyclone-caused GPS positioning errorand Its impact on remote oceanic island communities

Filić M., Filjar R.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2018

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Vol. 12, no. 4

663--670

EN

Satellite navigation gains importance in sustainable development of modern civilisation. With the increasing number of GNSS-based technology and socio-economic systems and services, satellite navigation has become an essential component of national infrastructure. This calls for novel requirements on GNSS positioning perfomance, and increasing need for resilient GNSS development. Here we examined the impact of rapidly developing tropical cyclone on GPS positioning performance degradation, and the resulting impact on oceanic non-navigation and navigation GPS applications. We presented the methodology for indirect simulation-based GPS positioning performance evaluation through utilisation of experimental GPS observations, GNSS Software-Defined Radio (SDR) receiver, and a statistical analysis and framework we developed in the R environment for scientific computing. We identified alteration of GPS positioning error components time series statistical properties, and discuss the potential impact on GPS-based services essential for remote oceanic island communities. Manuscript concludes with the summary of findings, proposal for recommendations on improved GNSS resilience, and an outline for future research.

5

Elements of Tropical Cyclones Avoidance Procedure

Wiśniewski B., Kaczmarek P.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2012

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Vol. 6, no. 1

119--122

EN

The updated version of the Cyclone II program was used for analyzing hundreds of cases where ships were facing dozens of developed cyclones. The program generates directions for navigators that are recommended for consideration before making decisions on passing around or avoiding tropical cyclones. Three specific situations were defined where a vessel may enter the area affected by a tropical cyclone, and its commander must consider three recommendations for safe passing of the cyclone: – vessel – cyclone encounter, where if on opposite course, the most effective is course alteration; – when the ship overtakes the cyclone, speed reduction is the most effective action; – when the vessel and the cyclone are on crossing routes (30 ÷ 90°), a slight decrease in speed or a slight course alteration or both actions can be effective.

6

Dynamiczne programowanie trasy statku z uwzględnieniem omijania cyklonów tropikalnych

Medyna P., Wiśniewski B., Chomski J.

Zeszyty Naukowe / Akademia Morska w Szczecinie

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2006

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nr 11 (83)

211-222

PL

Zaprezentowano obliczenia wyboru najkorzystniejszej trasy statku na oceanie z uwzględnieniem omijania cyklonów tropikalnych na Północnym Atlantyku. Testowania wykonano dla podróży statku m/v "Daszyński" w rzeczywistych warunkach pogodowych od 26.09.2004 r. do 6.10.2004 r., gdy na Atlantyku Północnym wystąpiły cyklony "Jeanne" i "Lisa". Zastosowano program obliczeniowy wykorzystujący algorytmy ewolucyjne.

EN

The most beneficial ship's route calculations on the ocean are presented, taking into consideration tropical cyclone avoidance. Tests were made for the m/v "Daszynski" voyage using real weather data during 26.IX.04 - 06.X.04, when the North Atlantic was haunted by the tropical cyclons "Jeanne" and "Lisa". A computational program based on evolutional algorithms was used.