Sea level the warmer water expands. For at least the last 100 years, sea level has been rising at an average rate of about per year. Most of this rise can be attributed to the increase in temperature of the sea and the resulting slight thermal expansion of the upper of sea water. Additional contributions, as much as one-quarter of the total, come from water sources on land, such as melting snow and glaciers and extraction of groundwater for irrigation and other agricultural and human uses. Pilots can estimate height above sea level with an altimeter set to a defined barometric pressure.
Eustatic sea level molecular motion, thus water molecules will occupy a lesser space. • Thermal expansion may also be influenced by ocean salinity. As continental ice accumulates, the ocean water freezes onto land but the salt it carried will mostly remain in the ocean. Thus, as ice sheets increase, ocean salinity also increases (and vice-versa). An increase in salinity will increase the density of the ocean basin. Melting of ice sheets and a decrease of ocean salinity will effectively decrease the density of the water. Eustatic sea level The eustatic sea level is the distance from the center of the earth to the