Method for predicting depth distribution of predetermined water temperature zone, method and system for delivering fishing ground prediction information of migratory fish

A fishing ground prediction information delivery system for migratory fish, comprising:

• means for acquiring observation data on water temperature, salinity and water depth measured at a plurality of observation spots in a target sea area, past data on water temperature, salinity and water depth at a large number of spots in the target sea area, and an absolute dynamic topography η1 at each of a plurality of observation spots in a target sea area and an absolute dynamic topography η2 at each of the large number of spots in the target sea area which were measured by satellite;
• means for determining a depth h from a sea surface to a water zone of a predetermined water temperature at each observation spot and respective densities ρ1 and ρ2 of upper and lower layers above and below the water zone, based on the observation data, calculating a relative density coefficient ε=(ρ2−ρ1)/ρ2 and ε×h, determining a slope α and a intercept β from the linear regression equation, η1=α(ε×h)+β, based on an ordinate axis which represents η1 and an abscissa axis which represents ε×h, calculating a relative density coefficient ε′ based on the past data, and calculating a depth h′ of a water zone of a predetermined water temperature at each of the large number of spots, based on an equation, η2=α(ε′×h′)++β;
• means for carrying out imaging of a depth distribution of a predetermined water temperature in the entire target sea area, based on the depth h and h′ of the predetermined water temperature at the large number of spots;
• and
• means for delivering the resulting image, as a fishing ground prediction for migratory fish which migrate in the predetermined water temperature, to a fishing ground site.

A fishery prediction information delivery system for migratory fish, comprising a receiver section, a central processing unit, and a transmitter section, wherein

• said receiver section is configured to acquire means for acquiring observation data on water temperature, salinity and water depth measured at a plurality of observation spots in a target sea area, past data on water temperature, salinity and water depth at a large number of spots in the target sea area, and an absolute dynamic topography η1 at each of the plurality of observation spots in a target sea area and an absolute dynamic topography η2 at each of the large number of spots in the target sea area which were measured by satellite,
• said central processing unit includes observation spot data calculating means for determining a depth h from a sea surface to a water zone of a predetermined water temperature at each observation spot and respective densities ρ1 and ρ2 of upper and lower layers above and below the water zone, based on the observation data, and calculating a relative density coefficient ε=(ρ2−ρ1)/ρ2 and ε×h, scatter diagram processing means for preparing a scatter diagram for every observation spot, based on an ordinate axis which represents η1 and an abscissa axis which represents ε×h, and determining the slope α and the intercept β from the linear regression equation, η1=α(ε×h)+β, multi-spot data calculating means for calculating a relative density coefficient ε′ based on the past data and calculating a depth h′ of a predetermined water temperature at each of the large number of spots, based on an equation, η2=α(ε′×h′)+β, and
• said transmitter section is configured to deliver, as a fishing ground prediction for migratory fish which migrate in a predetermined water temperature, a depth distribution of the predetermined water temperature in the entire target sea area, based on the depth h and h′ of the predetermined water temperature at the large number of spots, to a fishing ground site.