That's because oxygen wants to react; it can form compounds with nearly every other element on the periodic table. So how did Earth end up with an atmosphere made up of roughly 21 percent of the stuff? The answer is tiny organisms known as cyanobacteria, or blue-green algae. These microbes conduct photosynthesis:
|The Origin of Oxygen in Earth's Atmosphere - Scientific American||Humans first witnessed Earth as a complete orb floating in the inky blackness of space in December when Apollo 8 carried astronauts around the Moon.|
|Great Earth Environments |||For example, rock layers show the sequence of geological events, and the presence and amount of radioactive elements in rocks make it possible to determine their ages.|
|Earth & Environment | Science News||By Early Modern Englishmany nouns were capitalized, and the earth became and often remained the Earth, particularly when referenced along with other heavenly bodies. More recently, the name is sometimes simply given as Earth, by analogy with the names of the other planets.|
Lake A lake from Latin lacus is a terrain featurea body of water that is localized to the bottom of basin. A body of water is considered a lake when it is inland, is not part of an oceanand is larger and deeper than a pond.
Natural lakes on Earth are generally found in mountainous areas, rift zonesand areas with ongoing or recent glaciation. Other lakes are found in endorheic basins or along the courses of mature rivers.
In some parts of the world, there are many lakes because of chaotic drainage patterns left over from the last Ice Age. All lakes are temporary over geologic time scales, as they will slowly fill in with sediments or spill out of the basin containing them.
Pond A pond is Earth environments i 2 body of standing watereither natural or man-made, that is usually smaller than a lake. A wide variety of man-made bodies of water are classified as ponds, including water gardens designed for aesthetic ornamentation, fish ponds designed for commercial fish breeding, and solar ponds designed to store thermal energy.
Ponds and lakes are distinguished from streams by their current speed. While currents in streams are easily observed, ponds and lakes possess thermally driven micro-currents and moderate wind driven currents.
These features distinguish a pond from many other aquatic terrain features, such as stream pools and tide pools. Human impact on water[ edit ] Humans impact the water in different ways such as modifying rivers through dams and stream channelizationurbanizationand deforestation.
These impact lake levels, groundwater conditions, water pollution, thermal pollution, and marine pollution. Humans modify rivers by using direct channel manipulation.
Dams are good for humans, some communities need the reservoirs to survive. However, reservoirs and dams may negatively impact the environment and wildlife.
Dams stops fish migration and the moving of organisms down stream. Urbanization effects the environment because of deforestation and changing lake levels, groundwater conditions, etc. Deforestation and urbanization go hand in hand.
Deforestation may cause flooding, declining stream flow, and changes in riverside vegetation. The changing vegetation occurs because when trees cannot get adequate water they start to deteriorate, leading to a decreased food supply for the wildlife in an area.
A view of Earth's troposphere from an airplane. Lightning is an atmospheric discharge of electricity accompanied by thunderwhich occurs during thunderstorms and certain other natural conditions.
The thin layer of gases that envelops the Earth is held in place by the planet's gravity. The remaining gases are often referred to as trace gases,  among which are the greenhouse gases such as water vapor, carbon dioxide, methane, nitrous oxide, and ozone.
Filtered air includes trace amounts of many other chemical compounds. Air also contains a variable amount of water vapor and suspensions of water droplets and ice crystals seen as clouds. Many natural substances may be present in tiny amounts in an unfiltered air sample, including dustpollen and sporessea sprayvolcanic ashand meteoroids.
Various industrial pollutants also may be present, such as chlorine elementary or in compoundsfluorine compounds, elemental mercuryand sulphur compounds such as sulphur dioxide [SO2].
The ozone layer of the Earth's atmosphere plays an important role in depleting the amount of ultraviolet UV radiation that reaches the surface. The atmosphere also retains heat during the night, thereby reducing the daily temperature extremes.
Layers of the Atmosphere[ edit ] Principal layers[ edit ] Earth's atmosphere can be divided into five main layers. These layers are mainly determined by whether temperature increases or decreases with altitude.
From highest to lowest, these layers are: The outermost layer of Earth's atmosphere extends from the exobase upward, mainly composed of hydrogen and helium.
The top of the thermosphere is the bottom of the exosphere, called the exobase. It is the layer where most meteors burn up upon entering the atmosphere. The troposphere is mostly heated by transfer of energy from the surface, so on average the lowest part of the troposphere is warmest and temperature decreases with altitude.
The tropopause is the boundary between the troposphere and stratosphere. Other layers Within the five principal layers determined by temperature are several layers determined by other properties. The ozone layer is contained within the stratosphere.
It forms the inner edge of the magnetosphere.The discovery of seven Earth-sized planets in the TRAPPIST-1 system have lit a new fire in the search for life.
This is the resource page for all images, videos, . Oct 22, · The Earth & Environment page features the latest news in climate, earth, agriculture, ecosystems, toxicology, pollution, sustainability, oceans and more.
Stage 2 THE EARTH'S ENVIRONMENT. OUTCOMES. GE examines features and characteristics of places and environments; GE describes the ways people, places and environments interact animals and people and learn about the ways people value environments, including Aboriginal and Torres Strait Islander Peoples.
Students identify sustainable. Welcome to the family, welcome to Great Earth Environments! Meet the Business Owner. Neil S. Business Owner Neil Spain is the owner/operator of Great Earth Environments with over 30 years experience in home design and construction.
Pacific Christian College psychology major and Golden West college certificate in environment.4/4(5). See what's new in Google Earth Pro by reading the release notes below. Earth version Here are highlights of the fixes, changes and improvements we've made for this release of Google.
Earth & Environment. The "third rock from the Sun"—Earth. With an orbit neither too close nor too far from the Sun, it occupies a unique position in the Solar System.