Earths Water The water on earth is spread
- Slides: 104
Earth’s Water
The water on earth is spread through the lithosphere, hydrosphere and the atmosphere layers.
The lithosphere is the solid, rocky crust covering the entire planet.
Water is a major factor in weathering and erosion of rocks and the rock cycle.
erosion
The hydrosphere is composed of all of the water on or near the earth. This includes the ocean, rivers, lakes, and even the moisture in the air.
97% of the earth's water is in the ocean.
The atmosphere contains water in the form of water vapor and precipitation.
OCEANS
Most of the earth is covered by ocean.
Oceans give us food and help keep the air temperature steady.
Arctic Ocean Pacific Ocean Atlantic Ocean Southern Ocean Pacific Ocean Indian Ocean
On the ocean bed there are mountains, valleys and even volcanoes.
Food provided by the ocean is fish, shellfish, and seaweed.
Kelp, a kind of seaweed, provides algin, which is used as a thickening in ice cream, salad dressing and cosmetics.
FYI There are estimated to be between 500, 000 and 5, 000 marine species not yet discovered.
It is important to us that the oceans stay healthy.
They drive our climate and weather.
Oceans provide a livelihood for many millions of people worldwide through fishing, energy and mineral resources, shipping, and leisure activities
Oceans pose threats through floods, tsunamis, storms, sea level change and coastal erosion.
More than half the world’s population lives near the sea.
Most waste eventually ends up in the oceans, with the result that marine pollution is a global problem - every part of every ocean is now affected.
Oceans play a big part in maintaining a healthy environment.
One of their jobs is to soak 2. up CO
The oceans absorb about 1/4 of the 2 CO we create when we burn fossil fuels.
If not for the oceans, we'd be in even worse trouble 2 with too much CO.
The oceans also soak up heat and distribute it more evenly around the Earth.
The top few meters of the ocean stores as much heat as Earth's entire atmosphere.
That means that as the planet warms, it's the ocean that gets most of the extra energy.
But if the ocean gets too warm, then the plants and animals that live in it must adapt--or die.
Algae and plankton are at the bottom of the food chain. Plankton includes many different kinds of tiny animals, plants or bacteria that just float and drift in the ocean.
Other tiny animals such as krill (sort of like little shrimp) eat the plankton.
Fish and even whales and seals feed on the krill.
In some parts of the ocean, krill populations have dropped by over 80 percent.
Krill like to breed in really cold water and as the ocean warms, their breeding slows down.
Scarcity of krill causes a decrease in food for all the ocean’s animals.
Another problem is the ocean is becoming more acidic.
What does this mean? Liquids are either acid or alkaline.
Normally, ocean water is less acidic than fresh water.
Unfortunately, as the ocean absorbs more and more carbon dioxide from the atmosphere, it becomes more acidic.
The alkalinity of the ocean is very important in maintaining the balance needed for animals to make protective shells.
If the water is too acidic, the animals may not be able to make strong shells.
Corals could also be affected, since their skeletons are made of the same shell-like material.
Coral reefs are an essential part of ocean ecosystems and are home to over 25% of all known species of marine life.
75% of the world’s coral reefs are already at risk.
Unless things change, more than 90% of coral reefs will at risk by 2030 and all the world’s reefs will be threatened by 2050.
Scientists have determined the main causes of threats to the oceans include climate change, overfishing, pollution and habitat loss.
Other factors include an increase in areas of low oxygen levels (42 areas in 1950 -783 sites today) and even dead zones, which areas with no oxygen in the water.
It is estimated that about two million tons of plastic enter the ocean each year from rivers.
More than half of this plastic is less dense than the water, meaning that it will not sink.
The Great Pacific Garbage Patch (GPGP) is the largest of the five offshore plastic accumulation zones in the world’s oceans.
It is located halfway between Hawaii and California.
The GPGP covers an estimated surface area of 1. 6 million square kilometers, an area twice the size of Texas or three times the size of France.
Large pieces of plastic deteriorate into small pieces called microplastics, usually as a result of sun exposure, waves, marine life and temperature changes.
These small pieces are very difficult to remove and are often mistaken for food by marine animals.
Besides the risk of eating bits of plastic, animals can become entangled in such items as fishing nets and 6 -pack soda rings.
Microplastics also pose a risk to humans.
Chemicals enter the body of the animal feeding on the plastic, and as the feeder becomes prey, the chemicals will pass to the predator making their way up the food web that includes humans.
Taking Water for Granted
Today nearly 1 billion people in the world don't have access to clean water.
Water scarcity is either the lack of enough water or lack of access to safe water.
That is approximately 1/3 of the world’s population or basically 1 in every eight people in the world.
31/2 million people die each year from water-related disease.
Every day 4, 500 children under the age of 5 years old die because of a sickness related to unclean water.
1 out of 6 people in the world has no access to clean water within a mile of their home.
Sometimes there is water, but not enough money to get it.
Other times, it is an area that lacks enough water for its population.
In a day, Europeans use about 50 gallons of water. American use 100 gallons.
Those living in sub. Saharan Africa use 2 -5 gallons per day.
Many people don’t realize how much water is needed to manufacture things we use.
It takes 10 gallons of water to make a single slice of bread, 713 gallons to produce a cotton t-shirt, 1, 000 gallons to make 1 gallon of milk, and 634 gallons to produce 1 burger.
Surface Tension