Carbon cycles between Earth, atmosphere and oceans, affecting our climate
What Goes Around Comes Around
We live in time when preserving environment is getting important. If we are not going to see after environment there will be nothing for our children and generations to come. One of the biggest problems of humankind is insufficient care for nature. This can be seen through disappearing of tropical forest which represents Earths lungs where 40% of atmosphere oxygen through photosynthesis is produced.
People especially those from third world countries are not conscious enough or they do not care about what is happening with our forests. Kids and youngsters are those who are most sensitive to problems and to solve them and that is why so important to bring them to the problems so they will realize them. They should recognize the problematic of modern world and society that appears through excessive wood cutting and exploitation of natural resources as also extinction of various animal and plant species.
Children are our greatest hope and that is why our tomorrow should be built through them.
Carbon is the fourth most abundant element in the universe and the building block of life on Earth.
Carbon moves throughout the Earth — between the atmosphere, the oceans, sedimentary rock, soil and plants and animals — in what scientists call the carbon cycle.
To predict the behavior of Earth’s climate system in the future, we must be able to understand the functioning of the carbon system and predict the evolution of atmospheric carbon dioxide.
In its pure form carbon exists as diamond or graphite, the lead in pencils. Bound to oxygen, hydrogen and other carbon atoms, carbon forms essential compounds: sugars and fats that provide energy for plants and animals; petroleum, coal and natural gas that power human activity; and carbon dioxide and methane, atmospheric gases that trap heat from the sun and warm the Earth.
Plants, algae and some bacteria take up carbon dioxide from the atmosphere or oceans and convert it into sugars (carbon bound to other carbon, hydrogen and oxygen atoms), a process called photosynthesis. Animals eat sugar, a source of energy, and exhale carbon dioxide (carbon bound to two oxygen atoms) — respiration.
Animals and plants die and are buried in the earth, but their carbon compounds remain intact, a source of energy for microbes that feast on their remains and produce carbon dioxide and methane (carbon bound to four hydrogen atoms), some of which remains in the soil, some of which is released into the atmosphere.
Sometimes, plant and animal remains are buried in the earth or sink to the ocean floor and are protected from microbes. Over hundreds of millions of years animal remains are compressed deeper and deeper into the earth. Tissue and bone are destroyed but the carbon still remains, having formed compounds called hydrocarbons, long chains of carbon atoms bound to each other and to hydrogen atoms. Hydrocarbons are the main component of coal and petroleum — fossil fuels.
Humans use fossil fuels to produce heat and electricity, and in doing so the hydrocarbons in fossil fuels are converted into carbon dioxide and released into the atmosphere. Atmospheric carbon dissolves into the oceans or is taken up by plants and the cycle continues.
Rock in the Earth’s crust is composed of carbon, formed over millions of years when carbon binds to minerals. Carbon dioxide dissolved in the ocean forms bicarbonate, which combines with calcium to form limestone.
Weathering and erosion wash carbon compounds from rock in the Earth’s crust into the ocean. Carbon is also pulled beneath Earth’s crust — a process called subduction — and volcanoes, hot springs and geysers spew carbon dioxide and methane back into the atmosphere.
The geological components of the carbon cycle — weathering, erosion, subduction, the formation of fossil fuels — occur over millions of years. The biological components of the carbon cycle — photosynthesis, respiration, decomposition by microbes — occur over days to thousands of years.
On average, the amount of carbon that moves through biological components each year is 1,000 times greater than the amount of carbon that moves through geological components each year.
The problem now is that the carbon cycle is lopsided. It took hundreds of millions of years to sequester carbon deep in the earth and under the ocean floor, and humans have released much of that carbon into the atmosphere during the last century.
Humans are also destroying forests, releasing more carbon dioxide into the atmosphere and reducing the number of plants that absorb it from the atmosphere.
The atmosphere is overflowing with carbon, largely carbon dioxide. Some is absorbed by the oceans, some is absorbed by plants and soil, though how this happens is not well understood.