Iwo-jima is a small isolated volcanic island located in the Pacific Ocean. Due to the continuous upheaval of the island, foreshore area of this island has been increasing since 1911. Investigation is made to clarify the variation of the foreshore area of this island by analyzing the various field data obtained during the past three years. Analyses reveal that the foreshore area is currently increasing at an approximate rate of 180,000 square meters per year due to the unusual upheaval of the island exceeding 45 centimeters per year although seasonal variation of the foreshore area reaches 300,000 square meters.
SEASONAL VARIATION OF SWIMMING LAYER OF YELLOWFIN TUNA BY AREA OF DIFFERENT CURRENTS IN MID-WESTERN AND SOUTHWESTERN PARTS OF THE PACIFIC OCEAN