a graphic means of quantitative comparison by rectangles with lengths proportional to the measure of the data or things being compared. (source #5)

The earth-atmosphere energy balance is the balance between incoming energy from the Sun and outgoing energy from the Earth. Energy released from the Sun is emitted as shortwave light and ultraviolet energy. When it reaches the Earth, some is reflected back to space by clouds, some is absorbed by the atmosphere, and some is absorbed at the Earth's surface. (source #6)

The biosphere encompasses all life on Earth and extends from root systems to mountaintops and all depths of the ocean. It is critical for maintaining species diversity, regulating climate, and providing numerous ecosystem functions. (source #8)

The cryosphere encompasses the frozen parts of Earth, including glaciers and ice sheets, sea ice, and any other frozen body of water. The cryosphere plays a critical role in regulating climate and sea levels. (source #8)

The Geosphere is associated with solid portions of the Earth. It includes the continental and oceanic crust and all other layers of the Earth's interior. This includes all rocks, sediments and soils, surface landforms and the processes that shape the Earth's surface.(source #12)

The Hydrosphere is associated with water in the liquid state, which covers about 70% of the Earth's surface. Most liquid water is found in the oceans. Our Hydrosphere gives Earth a distinct appearance as a blue marble and separates us from other planets in the solar system. (source #12)

magma, molten or partially molten rock from which igneous rocks form. It usually consists of silicate liquid, although carbonate and sulfide melts occur as well. Magma migrates either at depth or to Earth’s surface and is ejected as lava. Several interrelated physical properties determine the characteristics of magma, including chemical composition, viscosity, dissolved gases, and temperature. (source # 7)

As these organisms die, certain microbes such as detritivores are able to participate in the decomposition of organic nitrogen into ammonia (ammonification), providing a constant supply of ammonia to be used in the process of nitrification. (source #7)

Nitrates and ammonia resulting from nitrogen fixation are assimilated into the specific tissue compounds of algae and higher plants. Animals then ingest these algae and plants, converting them into their own body compounds. (source #7)

reduction of nitrates or nitrites commonly by bacteria (as in soil) that usually results in the escape of nitrogen into the air. (source #5)