Estimation of freshwater discharge from the Kamchatka Peninsula to its surrounding oceans

Abstract

Study Region: Kamchatka Peninsula, Russian Federation. Study Focus: The strength of an overturning process of North Pacific sea water originating in the Sea of Okhotsk is determined by the sea water salinity in the area. Recent observations show that the overturning process is important to the entire North Pacific and is statistically related to the precipitation over the Kamchatka Peninsula (KP). This study uses estimations based on specific discharge and the Soil and Water Assessment Tool (SWAT) to verify and further explore the connection between the terrestrial freshwater discharge from KP and the overturning process. New Hydrological Insights for the Region: Previously inaccessible observed discharge data from 11 major rivers on the KP were obtained and analyzed for the first time. Based on the data we estimate annual discharge from the entire KP using the specific discharge and regression analysis, and we then simulate monthly discharge from the western KP using the SWAT model. Our result shows a significant negative correlation (r2 = 0.36, p < 0.01) between the interannual variation of sea water salinity in the overturning process area, and the variation of annual freshwater discharge from the western KP, therefore successfully verifies that freshwater discharge from the western KP is a critical factor that affects the strength of the overturning process.

Keywords

• Freshwater discharge
• Kamchatka Peninsula
• Sea of Okhotsk
• Dense shelf water
• SWAT model