A Stochastic Harmonic Oscillator Temperature Model for the Valuation of Weather Derivatives

Stochastic processes are employed in this paper to capture the evolution of daily mean temperatures, with the goal of pricing temperature-based weather options. A stochastic harmonic oscillator model is proposed for the temperature dynamics and results of numerical simulations and parameter estimation are presented. The temperature model is used to price a one-month call option and a sensitivity analysis is undertaken to examine how call option prices are affected when the model parameters are varied.

VULNERABILITY ANALYSIS OF YELLOWFIN TUNA (THUNNUS ALBACARES) BASED ON THE SEA SURFACE TEMPERATURE DYNAMICS

The vulnerability of fisheries to climatic variability can be measured through the capacity of species to adapt to environmental change. It was also analyzed based on the analysis of fish production and susceptibility. Yellowfin tuna is one of the main commodities in the Palabuhanratu fishing port of Indonesia. The condition of yellowfin tuna fisheries needs to be studied due to the vulnerability of existing fishing activities and climate change parameters. This research was conducted at the Palabuhanratu fishing port, Sukabumi, West Java, Indonesia. Productivity and susceptibility analysis was used to determine the value of species vulnerability to fishing activities and based on the climatic variability. This study aims to analyze the vulnerability level of capture fisheries, especially for yellowfin tuna, to the Sea Surface Temperature dynamics through the analysis of productivity and susceptibility. The research will support capture fisheries management based on vulnerability analysis by providing a novel integrated analysis between productivity, susceptibility, and oceanographic data. The result of the productivity score was 2.11, and the susceptibility score was 2.17. It means that yellowfin tuna landed at the Palabuhanratu fishing port was threatened by vulnerability, but yellowfin tuna can recover and survive properly against fishing activities. The vulnerability score of yellowfin tuna was 1.6, which was classified as low vulnerability. The relationship between climate change parameters, namely sea surface temperature, and yellowfin tuna parameter, has a low-medium correlation and has an inverse relationship. Sea surface temperature can affect the development of larvae and eggs and the availability of yellowfin tuna food. By knowing the vulnerability of the yellowfin tuna fishery, sustainable fisheries management can be carried out both based on the regulation of the fishing season and the level of utilization.

Modelling temperature dynamics in sewer systems – comparing mechanistic and conceptual modelling approaches

The vast majority of the energy consumed for urban water services is used to heat tap water. Heat recovery from wastewater is consequently an area of rapidly growing concern, both in research and by commercial interest, promoting the path towards a circular economy. To facilitate a system-wide evaluation of heat recovery from wastewater, this paper compares two one-dimensional models (mechanistic and conceptual) that can describe wastewater temperature dynamics in sewer pipe systems. The models are applied to successfully predict downstream wastewater temperature for sewer stretches in two Swedish cities (Linköping & Malmö). The root mean squared errors for the mechanistic model (Linköping Dataset1 – 0.33 °C; Linköping Dataset2 – 0.28 °C; Malmö – 0.40 °C) and the conceptual model (Linköping Dataset1 – 0.32 °C; Linköping Dataset2 – 0.20 °C; Malmö – 0.44 °C) indicate that both models have similar predictive capabilities, encouraging the use of conceptual models to reduce data requirements and model calibration efforts. Both models are freely distributed and can be easily integrated with wastewater generation and treatment models to facilitate system-wide wastewater temperature dynamics analysis.