Q:

What is an isostatic adjustment?

A:

Quick Answer

Isostatic adjustment is a corrective factor that scientists use to account for the fact that the basins in the ocean have increased in size since the last cycle of glaciers came to an end. This is not the result of glaciers melting, but instead the recovery of the Earth's surface from the once heavy, thick ice sheets that covered the majority of Europe and North America.

Know More

Full Answer

The sheets that lay on the Earth's surface were several kilometers thick, and that significant weight caused major shifts in the planet's structure. As a result, part of the Earth's mantle is still emerging from beneath the oceans into land areas that previously featured glaciers, with the effect that the Earth has some land surfaces that are rising and some ocean depths still falling in relationship to the Earth's center.

This means that glacial isostatic adjustment, or GIA, is leading to a shift in sea level change of -0.3 millimeters per year. This is a minuscule correction magnitude, but the uncertainty involved is a minimum of 50 percent. In general, the ocean is actually gaining room over time, and the purpose of the isostatic adjustment is to make sea level reflect oceanographic phenomena only.

Learn more about Earth Science

Related Questions

  • Q:

    Why is the ocean salty?

    A:

    As rain is formed in the atmosphere, it absorbs carbon dioxide, making it slightly acidic when it falls on the land. This rain physically and chemically erodes the rock and carries various minerals and salts as it runs off into the ocean.

    Full Answer >
    Filed Under:
  • Q:

    Why is there unequal heating of land and water?

    A:

    Water and land heat unequally due to the fact that they produce different heating capacities. Heat capacity is defined as the amount of heat, measured in calories, required to change the temperature of a substance by one degree Celsius. Water has a higher heating capacity than land.

    Full Answer >
    Filed Under:
  • Q:

    What causes global winds?

    A:

    Global winds refer to the pattern of air movement all around the globe, and they result from the fact that the Earth receives unequal heating from the sun. Not only does the tilt of the Earth's axis mean that different parts of the planet receive disparate amounts of sunlight, but the oceans and lands also heat at different rates. The imbalance in temperature makes heat move toward the poles, both in the wind and in ocean currents. When horizontal variances in air pressure take place as a result, wind occurs.

    Full Answer >
    Filed Under:
  • Q:

    Why is ocean water salty?

    A:

    Ocean water is salty primarily due to the large amounts of chloride and sodium on land which are dissolved by rainfall and carried to the sea by rivers and streams. Hydrothermal vents and underwater volcanoes located on the seabed also contribute dissolved salts to the ocean.

    Full Answer >
    Filed Under:

Explore