The Earth System Is Changing
Earth is a dynamic place. Materials move around the Earth system in many different ways. Rocks form and reform through the rock cycle. Water flows through the water cycle. Elements move between living and nonliving parts of the Earth system through biogeochemical cycles like the carbon cycle and nitrogen cycle. Motions of the ocean and the atmosphere have an impact on the Earth system too.
But recently scientists have been noticing other changes in the Earth system that are due to global warming as well as changes in the way land is used and pollution. These changes are changing the regular patterns of the system.
According to recent research, as temperature continues to warm the cryosphere will continue to lose ice, the atmosphere and its weather patterns will change, and the biosphere will loose some plants and animal species while others move into new areas.
Scientists are also studying how the parts of the Earth system affect each other and how they impact climate. The Earth reacts when aspects of the system are changed because of warming. Some reactions shrink the amount of warming while other reactions lead to even more warming. These reactions are called feedbacks.
- Reactions of the Earth system that shrink the impacts of a change are called negative feedbacks. For example, as warming causes more evaporation, this creates more clouds in the atmosphere, potentially blocking more solar energy from entering the Earth system and reducing the amount of warming.
- Reactions that exaggerate the impacts are called positive feedbacks. For example, as global warming makes sea ice melt in the Arctic, less sunlight is reflected back out to space and more is absorbed, causing more warming.
Understanding the negative and positive feedbacks of the Earth system is an area of active research in climate science. Bringing new information about feedbacks into climate models will allow us to better predict how climate will continue to change in the future.