1.
Satellite imagery
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Satellite imagery consists of images of Earth or other planets collected by satellites. Imaging satellites are operated by governments and businesses around the world, Satellite imaging companies sell images under licence. Images are licensed to governments and businesses such as Apple Maps, the first images from space were taken on sub-orbital flights. The U. S-launched V-2 flight on October 24,1946 took one image every 1.5 seconds. With an apogee of 65 miles, these photos were from five times higher than the previous record, the first satellite photographs of Earth were made on August 14,1959 by the U. S. The first satellite photographs of the Moon might have made on October 6,1959 by the Soviet satellite Luna 3. The Blue Marble photograph was taken from space in 1972, and has very popular in the media. Also in 1972 the United States started the Landsat program, the largest program for acquisition of imagery of Earth from space, Landsat Data Continuity Mission, the most recent Landsat satellite, was launched on 11 February 2013. In 1977, the first real time satellite imagery was acquired by the United Statess KH-11 satellite system, all satellite images produced by NASA are published by NASA Earth Observatory and are freely available to the public. Several other countries have satellite imaging programs, and a collaborative European effort launched the ERS, there are also private companies that provide commercial satellite imagery. Images can be in visible colours and in other spectra, there are also elevation maps, usually made by radar images. Interpretation and analysis of imagery is conducted using specialized remote sensing applications. There are four types of resolution when discussing satellite imagery in remote sensing, spatial, spectral, temporal, and radiometric. GSD is a term containing the optical and systemic noise sources and is useful for comparing how well one sensor can see an object on the ground within a single pixel. For example, the GSD of Landsat is ~30m, which means the smallest unit that maps to a single pixel within an image is ~30m x 30m, the latest commercial satellite has a GSD of 0.41 m. This compares to a 0.3 m resolution obtained by some early military film based Reconnaissance satellite such as Corona, the resolution of satellite images varies depending on the instrument used and the altitude of the satellites orbit. For example, the Landsat archive offers repeated imagery at 30 meter resolution for the planet, Landsat 7 has an average return period of 16 days. For many smaller areas, images with resolution as high as 41 cm can be available, Satellite imagery is sometimes supplemented with aerial photography, which has higher resolution, but is more expensive per square meter
2.
NASA
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President Dwight D. Eisenhower established NASA in 1958 with a distinctly civilian orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29,1958, disestablishing NASAs predecessor, the new agency became operational on October 1,1958. Since that time, most US space exploration efforts have led by NASA, including the Apollo Moon landing missions, the Skylab space station. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle, the agency is also responsible for the Launch Services Program which provides oversight of launch operations and countdown management for unmanned NASA launches. NASA shares data with various national and international such as from the Greenhouse Gases Observing Satellite. Since 2011, NASA has been criticized for low cost efficiency, from 1946, the National Advisory Committee for Aeronautics had been experimenting with rocket planes such as the supersonic Bell X-1. In the early 1950s, there was challenge to launch a satellite for the International Geophysical Year. An effort for this was the American Project Vanguard, after the Soviet launch of the worlds first artificial satellite on October 4,1957, the attention of the United States turned toward its own fledgling space efforts. This led to an agreement that a new federal agency based on NACA was needed to conduct all non-military activity in space. The Advanced Research Projects Agency was created in February 1958 to develop technology for military application. On July 29,1958, Eisenhower signed the National Aeronautics and Space Act, a NASA seal was approved by President Eisenhower in 1959. Elements of the Army Ballistic Missile Agency and the United States Naval Research Laboratory were incorporated into NASA, earlier research efforts within the US Air Force and many of ARPAs early space programs were also transferred to NASA. In December 1958, NASA gained control of the Jet Propulsion Laboratory, NASA has conducted many manned and unmanned spaceflight programs throughout its history. Some missions include both manned and unmanned aspects, such as the Galileo probe, which was deployed by astronauts in Earth orbit before being sent unmanned to Jupiter, the experimental rocket-powered aircraft programs started by NACA were extended by NASA as support for manned spaceflight. This was followed by a space capsule program, and in turn by a two-man capsule program. This goal was met in 1969 by the Apollo program, however, reduction of the perceived threat and changing political priorities almost immediately caused the termination of most of these plans. NASA turned its attention to an Apollo-derived temporary space laboratory, to date, NASA has launched a total of 166 manned space missions on rockets, and thirteen X-15 rocket flights above the USAF definition of spaceflight altitude,260,000 feet. The X-15 was an NACA experimental rocket-powered hypersonic research aircraft, developed in conjunction with the US Air Force, the design featured a slender fuselage with fairings along the side containing fuel and early computerized control systems
3.
Moderate-resolution imaging spectroradiometer
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The instruments capture data in 36 spectral bands ranging in wavelength from 0.4 µm to 14.4 µm and at varying spatial resolutions. Together the instruments image the entire Earth every 1 to 2 days, MODIS has used the marine optical buoy for vicarious calibration. MODIS is succeeded by the VIIRS instrument on board the Suomi NPP satellite launched in 2011, the MODIS characterization support team is dedicated to the production of high-quality MODIS calibrated product which is a precursor to every geophysical science product. A detailed description of the MCST mission statement and other details can be found at MCST Web, with its low spatial resolution but high temporal resolution, MODIS data is useful to track changes in the landscape over time. The United States Forest Services Remote Sensing Applications Center analyzes MODIS imagery on a basis to provide information for the management. The following MODIS Level 3 datasets are available from NASA, as processed by the Collection 5 software, most of the data is available in the HDF-EOS format — a variant of Hierarchical Data Format prescribed for the data derived from Earth Observing System missions. Imaging spectroscopy NASA World Wind Official NASA site MODIS bands and spectral ranges MODIS Images of the Day MODIS Image of the Day – Google Gadget referring to MODIS image of the day
4.
Sky
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The sky is everything that lies above the surface of the Earth, including the atmosphere and outer space. In the field of astronomy, the sky is called the celestial sphere. This is viewed from Earths surface as a dome where the Sun, stars, planets. The celestial sphere is divided into regions called constellations. Usually, the sky is used informally as the point of view from the Earths surface, however. In some cases, such as in discussing the weather, the sky refers to only the lower, during daylight, the sky appears to be blue because air scatters blue sunlight more than it scatters red. At night, the sky appears to be a dark surface or region scattered with stars. During the day, the Sun can be seen in the sky obscured by clouds. In the night sky the Moon, planets and stars are visible in the sky, some of the natural phenomena seen in the sky are clouds, rainbows, and aurorae. Lightning and precipitation can also be seen in the sky during storms, birds, insects, aircraft, and kites are often considered to fly in the sky. Due to human activities, smog during the day and light pollution during the night are often seen above large cities. Except for light that directly from the sun, most of the light in the day sky is caused by scattering. The scattering due to molecule sized particles is greater in the forward and backward directions than it is in the lateral direction. Scattering is significant for light at all visible wavelengths but is stronger at the end of the visible spectrum, meaning that the scattered light is bluer than its source. The remaining sunlight, having lost some of its wavelength components. Scattering also occurs more strongly in clouds. Individual water droplets exposed to light will create a set of colored rings. If a cloud is thick enough, scattering from water droplets will wash out the set of colored rings
5.
France
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France, officially the French Republic, is a country with territory in western Europe and several overseas regions and territories. The European, or metropolitan, area of France extends from the Mediterranean Sea to the English Channel and the North Sea, Overseas France include French Guiana on the South American continent and several island territories in the Atlantic, Pacific and Indian oceans. France spans 643,801 square kilometres and had a population of almost 67 million people as of January 2017. It is a unitary republic with the capital in Paris. Other major urban centres include Marseille, Lyon, Lille, Nice, Toulouse, during the Iron Age, what is now metropolitan France was inhabited by the Gauls, a Celtic people. The area was annexed in 51 BC by Rome, which held Gaul until 486, France emerged as a major European power in the Late Middle Ages, with its victory in the Hundred Years War strengthening state-building and political centralisation. During the Renaissance, French culture flourished and a colonial empire was established. The 16th century was dominated by civil wars between Catholics and Protestants. France became Europes dominant cultural, political, and military power under Louis XIV, in the 19th century Napoleon took power and established the First French Empire, whose subsequent Napoleonic Wars shaped the course of continental Europe. Following the collapse of the Empire, France endured a succession of governments culminating with the establishment of the French Third Republic in 1870. Following liberation in 1944, a Fourth Republic was established and later dissolved in the course of the Algerian War, the Fifth Republic, led by Charles de Gaulle, was formed in 1958 and remains to this day. Algeria and nearly all the colonies became independent in the 1960s with minimal controversy and typically retained close economic. France has long been a centre of art, science. It hosts Europes fourth-largest number of cultural UNESCO World Heritage Sites and receives around 83 million foreign tourists annually, France is a developed country with the worlds sixth-largest economy by nominal GDP and ninth-largest by purchasing power parity. In terms of household wealth, it ranks fourth in the world. France performs well in international rankings of education, health care, life expectancy, France remains a great power in the world, being one of the five permanent members of the United Nations Security Council with the power to veto and an official nuclear-weapon state. It is a member state of the European Union and the Eurozone. It is also a member of the Group of 7, North Atlantic Treaty Organization, Organisation for Economic Co-operation and Development, the World Trade Organization, originally applied to the whole Frankish Empire, the name France comes from the Latin Francia, or country of the Franks
6.
Cirrus cloud
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Cirrus is a genus of atmospheric cloud generally characterized by thin, wispy strands, giving the type its name from the Latin word cirrus, meaning a ringlet or curling lock of hair. This cloud can form anywhere between 16,500 and 45,000 feet in the sky, the strands of cloud sometimes appear in tufts of a distinctive form referred to by the common name of mares tails. On planet Earth, cirrus generally appears white or light gray in color and it forms when water vapor undergoes deposition at altitudes above 5,500 m in temperate regions and above 6,400 m in tropical regions. It also forms from the outflow of tropical cyclones or the anvils of cumulonimbus cloud, since cirrus clouds arrive in advance of the frontal system or tropical cyclone, it indicates that weather conditions may soon deteriorate. While it indicates the arrival of precipitation, cirrus clouds only produce fall streaks, jet stream-powered cirrus can grow long enough to stretch across continents while remaining only a few kilometers deep. When visible light interacts with the ice crystals in cirrus cloud, it produces optical phenomena such as sun dogs, Cirrus is known to raise the temperature of the air beneath the main cloud layer by an average of 10 °C. When the individual filaments become so extensive that they are virtually indistinguishable from one another, convection at high altitudes can produce another high-based genus called cirrocumulus, a pattern of small cloud tufts that contain droplets of supercooled water. Cirrus clouds form on planets, including Mars, Jupiter, Saturn, Uranus. They have even seen on Titan, one of Saturns moons. Some of these extraterrestrial cirrus clouds are composed of ammonia or methane ice rather than water ice, the term cirrus is also used for certain interstellar clouds composed of sub-micrometer-sized dust grains. Cirrus cloud ranges in thickness from 100 m to 8,000 m, with an average thickness of 1,500 m. There are, on average,30 ice crystals per liter, but this ranges from one ice crystal per 10,000 liters to 10,000 ice crystals per liter, a difference of eight orders of magnitude. The length of each of these ice crystals is usually 0.25 millimeters long, the ice crystals in contrails are much smaller than those in naturally occurring cirrus cloud, as they are around 0.001 millimeters to 0.1 millimeters in length. Cirrus can vary in temperature from −20 °C to −30 °C, the ice crystals in cirrus clouds have different shapes in addition to different sizes. Some shapes include solid columns, hollow columns, plates, rosettes, the shape of the ice crystals is determined by the air temperature, atmospheric pressure, and ice supersaturation. Cirrus in temperate regions typically have the shapes segregated by type, in the northern Arctic region, cirrus tend to be composed of only the columns, plates, and conglomerations, and these crystals tend to be at least four times larger than the minimum size. In Antarctica, cirrus are usually composed of only the columns, scientists have studied the characteristics of cirrus using several different methods. One, Light Detection and Ranging, gives highly accurate information on the altitude, length
7.
Sun
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The Sun is the star at the center of the Solar System. It is a perfect sphere of hot plasma, with internal convective motion that generates a magnetic field via a dynamo process. It is by far the most important source of energy for life on Earth. Its diameter is about 109 times that of Earth, and its mass is about 330,000 times that of Earth, accounting for about 99. 86% of the total mass of the Solar System. About three quarters of the Suns mass consists of hydrogen, the rest is mostly helium, with smaller quantities of heavier elements, including oxygen, carbon, neon. The Sun is a G-type main-sequence star based on its spectral class and it formed approximately 4.6 billion years ago from the gravitational collapse of matter within a region of a large molecular cloud. Most of this matter gathered in the center, whereas the rest flattened into a disk that became the Solar System. The central mass became so hot and dense that it eventually initiated nuclear fusion in its core and it is thought that almost all stars form by this process. The Sun is roughly middle-aged, it has not changed dramatically for more than four billion years and it is calculated that the Sun will become sufficiently large enough to engulf the current orbits of Mercury, Venus, and probably Earth. The enormous effect of the Sun on Earth has been recognized since prehistoric times, the synodic rotation of Earth and its orbit around the Sun are the basis of the solar calendar, which is the predominant calendar in use today. The English proper name Sun developed from Old English sunne and may be related to south, all Germanic terms for the Sun stem from Proto-Germanic *sunnōn. The English weekday name Sunday stems from Old English and is ultimately a result of a Germanic interpretation of Latin dies solis, the Latin name for the Sun, Sol, is not common in general English language use, the adjectival form is the related word solar. The term sol is used by planetary astronomers to refer to the duration of a solar day on another planet. A mean Earth solar day is approximately 24 hours, whereas a mean Martian sol is 24 hours,39 minutes, and 35.244 seconds. From at least the 4th Dynasty of Ancient Egypt, the Sun was worshipped as the god Ra, portrayed as a falcon-headed divinity surmounted by the solar disk, and surrounded by a serpent. In the New Empire period, the Sun became identified with the dung beetle, in the form of the Sun disc Aten, the Sun had a brief resurgence during the Amarna Period when it again became the preeminent, if not only, divinity for the Pharaoh Akhenaton. The Sun is viewed as a goddess in Germanic paganism, Sól/Sunna, in ancient Roman culture, Sunday was the day of the Sun god. It was adopted as the Sabbath day by Christians who did not have a Jewish background, the symbol of light was a pagan device adopted by Christians, and perhaps the most important one that did not come from Jewish traditions
8.
Climate change
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Climate change is a change in the statistical distribution of weather patterns when that change lasts for an extended period of time. Climate change may refer to a change in weather conditions. Climate change is caused by such as biotic processes, variations in solar radiation received by Earth, plate tectonics. Certain human activities have also identified as significant causes of recent climate change. Scientists actively work to understand past and future climate by using observations, more recent data are provided by the instrumental record. The most general definition of change is a change in the statistical properties of the climate system when considered over long periods of time. Accordingly, fluctuations over periods shorter than a few decades, such as El Niño, the term climate change is often used to refer specifically to anthropogenic climate change. Anthropogenic climate change is caused by activity, as opposed to changes in climate that may have resulted as part of Earths natural processes. In this sense, especially in the context of environmental policy, within scientific journals, global warming refers to surface temperature increases while climate change includes global warming and everything else that increasing greenhouse gas levels affect. A related term is climatic change, in 1966, the World Meteorological Organization proposed the term climatic change to encompass all forms of climatic variability on time-scales longer than 10 years, regardless of cause. Change was a given and climatic was used as an adjective to describe this kind of change, when it was realized that human activities had a potential to drastically alter the climate, the term climate change replaced climatic change as the dominant term to reflect an anthropogenic cause. Climate change was incorporated in the title of the Intergovernmental Panel on Climate Change, Climate change, used as a noun, became an issue rather than the technical description of changing weather. On the broadest scale, the rate at which energy is received from the Sun and this energy is distributed around the globe by winds, ocean currents, and other mechanisms to affect the climates of different regions. Factors that can shape climate are called climate forcings or forcing mechanisms, there are a variety of climate change feedbacks that can either amplify or diminish the initial forcing. Some parts of the system, such as the oceans and ice caps, respond more slowly in reaction to climate forcings. There are also key factors which when exceeded can produce rapid change. Forcing mechanisms can be internal or external. Internal forcing mechanisms are natural processes within the system itself
9.
Amazon rainforest
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The Amazon rainforest, also known in English as Amazonia or the Amazon Jungle, is a moist broadleaf forest in the Amazon biome that covers most of the Amazon basin of South America. This basin encompasses 7,000,000 square kilometres, of which 5,500,000 square kilometres are covered by the rainforest and this region includes territory belonging to nine nations. States or departments in four nations contain Amazonas in their names, the name Amazon is said to arise from a war Francisco de Orellana fought with the Tapuyas and other tribes. The women of the tribe alongside the men, as was their custom. Orellana derived the name Amazonas from the Amazons of Greek mythology, the rainforest likely formed during the Eocene era. It appeared following a reduction of tropical temperatures when the Atlantic Ocean had widened sufficiently to provide a warm. Following the Cretaceous–Paleogene extinction event, the extinction of the dinosaurs, from 66–34 Mya, the rainforest extended as far south as 45°. Climate fluctuations during the last 34 million years have allowed savanna regions to expand into the tropics, during the Oligocene, for example, the rainforest spanned a relatively narrow band. It expanded again during the Middle Miocene, then retracted to a mostly inland formation at the last glacial maximum, however, the rainforest still managed to thrive during these glacial periods, allowing for the survival and evolution of a broad diversity of species. During the mid-Eocene, it is believed that the basin of the Amazon was split along the middle of the continent by the Purus Arch. Water on the eastern side flowed toward the Atlantic, while to the west water flowed toward the Pacific across the Amazonas Basin, as the Andes Mountains rose, however, a large basin was created that enclosed a lake, now known as the Solimões Basin. Within the last 5–10 million years, this accumulating water broke through the Purus Arch, there is evidence that there have been significant changes in Amazon rainforest vegetation over the last 21,000 years through the Last Glacial Maximum and subsequent deglaciation. There is debate, however, over how extensive this reduction was, more than 56% of the dust fertilizing the Amazon rainforest comes from the Bodélé depression in Northern Chad in the Sahara desert. The dust contains phosphorus, important for plant growth, the yearly Sahara dust replaces the equivalent amount of phosphorus washed away yearly in Amazon soil from rains and floods. Up to 50 million tonnes of Sahara dust per year are blown across the Atlantic Ocean, CALIPSO uses a laser range finder to scan the Earths atmosphere for the vertical distribution of dust and other aerosols. CALIPSO regularly tracks the Sahara-Amazon dust plume, CALIPSO has measured variations in the dust amounts transported— an 86 percent drop between the highest amount of dust transported in 2007 and the lowest in 2011. A possibility causing the variation is the Sahel, a strip of land on the southern border of the Sahara. When rain amounts in the Sahel are higher, the volume of dust is lower, the higher rainfall could make more vegetation grow in the Sahel, leaving less sand exposed to winds to blow away
10.
Sahara
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The Sahara is the largest hot desert and the third largest desert in the world after Antarctica and the Arctic. Its area of 9,200,000 square kilometres is comparable to the area of the United States. The desert comprises much of North Africa, excluding the fertile region on the Mediterranean Sea coast, the Atlas Mountains of the Maghreb, and the Nile Valley in Egypt and Sudan. It stretches from the Red Sea in the east and the Mediterranean in the north to the Atlantic Ocean in the west, where the landscape gradually changes from desert to coastal plains. To the south, it is bounded by the Sahel, a belt of tropical savanna around the Niger River valley. The Sahara can be divided into several regions including, the western Sahara, the central Ahaggar Mountains, the Tibesti Mountains, the Aïr Mountains, the Ténéré desert, the name Sahara is derived from ṣaḥārā, the plural of the Arabic word for desert. The Sahara covers large parts of Algeria, Chad, Egypt, Libya, Mali, Mauritania, Morocco, Niger, Western Sahara, Sudan and it covers 9 million square kilometres, amounting to 31% of Africa. If all areas with an annual precipitation of less than 250 mm were included. It is one of three physiographic provinces of the African massive physiographic division. The Sahara is mainly rocky hamada, Ergs form only a minor part, wind or rare rainfall shape the desert features, sand dunes, dune fields, sand seas, stone plateaus, gravel plains, dry valleys, dry lakes, and salt flats. Unusual landforms include the Richat Structure in Mauritania, several deeply dissected mountains, many volcanic, rise from the desert, including the Aïr Mountains, Ahaggar Mountains, Saharan Atlas, Tibesti Mountains, Adrar des Iforas, and the Red Sea hills. The highest peak in the Sahara is Emi Koussi, a volcano in the Tibesti range of northern Chad. The central Sahara is hyperarid, with sparse vegetation, the northern and southern reaches of the desert, along with the highlands, have areas of sparse grassland and desert shrub, with trees and taller shrubs in wadis, where moisture collects. In the central, hyperarid region, there are subdivisions of the great desert, Tanezrouft, the Ténéré, the Libyan Desert, the Eastern Desert. These extremely arid areas often receive no rain for years, the northern limit also corresponds to the 100 mm isohyet of annual precipitation. To the south, the Sahara is bounded by the Sahel, the southern limit of the Sahara is indicated botanically by the southern limit of Cornulaca monacantha, or northern limit of Cenchrus biflorus, a grass typical of the Sahel. According to climatic criteria, the limit of the Sahara corresponds to the 150 mm isohyet of annual precipitation. The Sahara is the worlds largest low-latitude hot desert and this steady descending airflow causes a warming and a drying effect in the upper troposphere
11.
Nature
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Nature, in the broadest sense, is the natural, physical, or material world or universe. Nature can refer to the phenomena of the world. The study of nature is a part of science. Although humans are part of nature, human activity is understood as a separate category from other natural phenomena. The word nature is derived from the Latin word natura, or essential qualities, innate disposition, and in ancient times, literally meant birth. Natura is a Latin translation of the Greek word physis, which related to the intrinsic characteristics that plants, animals. This usage continued during the advent of scientific method in the last several centuries. Within the various uses of the word today, nature often refers to geology, for example, manufactured objects and human interaction generally are not considered part of nature, unless qualified as, for example, human nature or the whole of nature. Depending on the context, the term natural might also be distinguished from the unnatural or the supernatural. Earth is the planet known to support life, and its natural features are the subject of many fields of scientific research. Within the solar system, it is third closest to the sun, it is the largest terrestrial planet and its most prominent climatic features are its two large polar regions, two relatively narrow temperate zones, and a wide equatorial tropical to subtropical region. Precipitation varies widely with location, from several metres of water per year to less than a millimetre,71 percent of the Earths surface is covered by salt-water oceans. The remainder consists of continents and islands, with most of the land in the Northern Hemisphere. Earth has evolved through geological and biological processes that have left traces of the original conditions, the outer surface is divided into several gradually migrating tectonic plates. The interior remains active, with a layer of plastic mantle. This iron core is composed of a solid phase. Convective motion in the core generates electric currents through dynamo action, the atmospheric conditions have been significantly altered from the original conditions by the presence of life-forms, which create an ecological balance that stabilizes the surface conditions. Geology is the science and study of the solid and liquid matter that constitutes the Earth, the geology of an area evolves through time as rock units are deposited and inserted and deformational processes change their shapes and locations
