Carbon is an important chemical element in all living things lives. It exists in solid, dissolved and gaseous forms on Earth. Carbon continually flows between plants, animals and microbes; minerals in the Earth’s crust; and the atmosphere. This natural process is called the carbon cycle.
Fossil fuels are a type of energy source formed from carbon-containing organic matter buried and compressed underground millions of years ago. These materials include coal, oil and natural gas.
In the past, most of these carbon-containing rocks were found in sedimentary rock layers covering much of Earth’s surface. Over time, the minerals that formed these layers were subjected to geothermal heat, transforming them into fossil fuels.
These fossil fuels are now used worldwide in electricity generation, transportation and manufacturing industries. They are also responsible for most greenhouse gases that trap and release heat into the atmosphere.
Forests provide a home for 80% of all the planet’s land animals and plants. When forests are destroyed, the carbon stored in them is released into the atmosphere as greenhouse gases.
The most significant drivers of deforestation are agriculture, including cattle ranching and logging for timber and other products. These activities account for 80% of tropical deforestation and contribute to global warming.
The deforestation rate has increased in many parts of the world over the last decade due to growing demand for beef and soy, government development policies that encourage forest expansion, and the increasing vulnerability of rainforest ecosystems to drought and fire. While the trend is positive overall, deforestation still severely threatens the planet’s health.
Every 3 to 5 seconds, nerve impulses stimulate the breathing process, or ventilation, which moves air through a series of passages into and out of the lungs.
The lungs also exchange gases with the blood, transporting oxygen and carbon dioxide to and from tissues throughout the body. In addition, the cells utilize oxygen for their specific activities: this is called cellular respiration.
The human respiratory system consists of a complex network of organs and tissues that capture oxygen from the atmosphere and transfer it to the lungs for respiration. The method includes the nose, pharynx, trachea and lungs.
The decomposition of plant material is essential to the environment. Without it, nutrients from dead leaves and stems would remain locked up in the plant cells, slowing growth.
The significant organisms that break down dead organic matter are fungi and bacteria. They extract nitrogen from the material and make proteins they need to grow.
They also remove carbon dioxide and sulfates from the decomposing material, increasing oxygen in the air.
Several factors affect decomposition rates, including the temperature of the soil and water availability. Disturbance also accelerates decomposition by exposing new surfaces and temporarily increasing soil moisture, stimulating respiration from soil biota.
The oceans have a huge carbon sink, taking up more than 40% of the extra CO2 we’ve released since the industrial era. This helps to slow climate change by absorbing excess CO2, which otherwise would increase in the atmosphere.
However, increasing amounts of carbon dioxide in the ocean hurt marine life: it changes the chemistry of seawater and can cause ocean acidification. This can erode the calcium carbonate that makes up mussel shells and coral skeletons, disrupting vital functions like fish breathing.
Scientists have long puzzled over what causes the ocean to absorb so much of our carbon dioxide. A new study suggests that the ozone layer and wind patterns are linked to human-caused changes to the atmosphere.