COASTAL ENVIRONMENTS OF THE WESTERN KARA AND EASTERN BARENTS SEAS

Satellite images from the Kara Sea show that, until July, fast-ice ext ends along the coast and fills the estuaries of the Ob' and Yenisey ri vers. It is separated from offshore drift-ice by a region of open wate r, comprising a flaw lead/polynya. By August, much of the fast and dri ft-ice has melted and retreated from the southwestern Kara Sea, leavin g behind a persistent patch of sea-ice east of Novaya Zemlya. Because both the Ob' and Yenisey rivers discharge water throughout the winter, the fast-ice is likely to incorporate river-borne contaminants by bot tom adfreezing. During peak river discharge in June, the fast-ice rema ins in place, and is potentially influenced by the river outflow throu ghout the length of the estuary. Breakup and melting of the fast-ice i n July could release contaminants to the surface waters. By late July and August, when the fast-ice has disappeared, the river discharge is observed primarily along the shore in a zone that extends offshore mor e than 100 km. In fall, newly-forming ice may incorporate contaminants from the river plume, while in late winter, convection penetrating to the sea floor may allow resuspended sediments to be entrained in ice forming in the flaw lead/polynya. Drift-ice formed in this region coul d then advect contaminants offshore. The potential for exchange of wat er, ice and contaminants with the Barents Sea through Karskiye Vorota, south of Novaya Zemlya, is discussed in the context of the temperatur e and turbidity distribution observed in the satellite images.