Q:

What is an isostatic adjustment?

A:

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.

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.


Is this answer helpful?

Similar Questions

  • Q:

    What is an ocean current?

    A:

    An ocean current is "any more or less permanent or continuous, directed movement of ocean water that flows in one of the Earth's oceans," according to ScienceDaily.com. Currents are created by a variety of forces.

    Full Answer >
    Filed Under:
  • Q:

    How old is the Earth?

    A:

    According to scientists, the earth is about 4.5 billion years old. However, because of the constant upheavals in climate, plate tectonics, asteroid strikes and other events, most of the evidence of the earth's beginnings are lost.

    Full Answer >
    Filed Under:
  • Q:

    What is an ocean ecosystem?

    A:

    Ocean ecosystems or marine ecosystems are made up of a community of living and nonliving things found in a localized area in any ocean. In an ecosystem, the plant life and animal life support one another and are each dependent on the other for the success of the ecosystem.

    Full Answer >
    Filed Under:
  • 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:

Explore