Search results
Results from the WOW.Com Content Network
The opposite of transgression is regression where the sea level falls relative to the land and exposes the former sea bottom. During the Pleistocene Ice Age, so much water was removed from the oceans and stored on land as year-round glaciers that the ocean regressed 120 m, exposing the Bering land bridge between Alaska and Asia.
As the balance shifts between the global cryosphere and hydrosphere, more of the planet's water in ice sheets means less in the oceans. At the height of the last ice age , around 18,000 years ago, the global sea level was 120 to 130 m (390-425 ft) lower than today.
Water carried into the mantle eventually returns to the surface in eruptions at mid-ocean ridges and hotspots. [131]: 646 Estimates of the amount of water in the mantle range from 1 ⁄ 4 to 4 times the water in the ocean. [131]: 630–634 The deep carbon cycle is the movement of carbon through the Earth's mantle and core.
The effects of climate change on the water cycle have important negative effects on the availability of freshwater resources, as well as other water reservoirs such as oceans, ice sheets, the atmosphere and soil moisture. The water cycle is essential to life on Earth and plays a large role in the global climate system and ocean circulation.
The typical tidal range in the open ocean is about 1 metre (3 feet) – mapped in blue and green at right. Mean ranges near coasts vary from near zero to 11.7 metres (38.4 feet), [ 4 ] with the range depending on the volume of water adjacent to the coast, and the geography of the basin the water sits in. Larger bodies of water have higher ...
Ocean stratification is the natural separation of an ocean's water into horizontal layers by density. This is generally stable stratification , because warm water floats on top of cold water, and heating is mostly from the sun, which reinforces that arrangement.
The main factors affecting sea level are the amount and volume of available water and the shape and volume of the ocean basins. The primary influences on water volume are the temperature of the seawater, which affects density, and the amounts of water retained in other reservoirs like rivers, aquifers, lakes, glaciers, polar ice caps and sea ice.
The eustatic sea level (from Greek εὖ eû, "good" and στάσις stásis, "standing") is the distance from the center of the Earth to the sea surface. [1] [2] An increase of the eustatic sea level can be generated by decreasing glaciation, increasing spreading rates of the mid-ocean ridges or increasing the number of mid-oceanic ridges.