Density of water increases as temperature decreases
Temperature (degrees Kelvin)
Water masses of lower density floaton top of those with higher density
Density of water increases as amount of dissolved salts increases (salinity)
major surface currents (wind-driven)
Many large rivers drain freshwater into the Arctic Ocean
high latitude precipitation has been increasing
Retreat of North American (Laurentide) ice sheet
Northern Hemisphere Polar Ice
NASA/CSA Resources - Composite radar image draped on visible image
Image source: NASA Jet Propulsion Lab