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Aeroecology
Aeroecology is the discipline for studying how airborne life forms utilize and interact with other biotic and abiotic components of the atmosphere. The aerosphere is viewed as habitat and the way that organisms respond to and take advantage of the dynamic aeroscape has relevance to the ecology, evolution, and conservation of many of the world's bird, bat, insect, and plant species. The interactions and properties in the aerosphere, the zone that is closest to the Earth's surface, provide selective pressures that influence the size and shape of organisms, their behavioral, sensory, metabolic, and respiratory functions. In contrast to organisms that spend their entire lives on land or in water, organisms that use the aerosphere are almost immediately affected by changing conditions such as winds, air density, oxygen concentrations, precipitation, air temperature, sunlight, polarized light, moonlight, and geomagnetic and gravitational forces. Aeroecology has relied upon traditional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Kunz
Thomas H. Kunz (June 11, 1938 – April 13, 2020) was an American biologist specializing in the study of bats. He was credited with coining the study of aeroecology; additionally, he wrote several fundamental textbooks and publications on bat ecology. Early life Kunz grew up in Missouri. He credited his interest in biology to his fifth-grade teacher, who was passionate about silkworms. Education Kunz received a Bachelor of Arts in biology in 1961 and Master of Arts in education in 1962 from the University of Central Missouri. He went on to receive another Master of Arts from Drake University in biology in 1968, and gained his Doctor of Philosophy from the University of Kansas in systematics and ecology in 1971. Career Kunz taught high school in Kansas after receiving his MA in education. Kunz states that his first experience working with bats was before he attended Drake University. While caving, he and a friend encountered a Animal migration tracking, banded bat. He called in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aerosphere
An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A stellar atmosphere is the outer region of a star, which includes the layers above the opaque photosphere; stars of low temperature might have outer atmospheres containing compound molecules. The atmosphere of Earth is composed of nitrogen (78%), oxygen (21%), argon (0.9%), carbon dioxide (0.04%) and trace gases. Most organisms use oxygen for respiration; lightning and bacteria perform nitrogen fixation to produce ammonia that is used to make nucleotides and amino acids; plants, algae, and cyanobacteria use carbon dioxide for photosynthesis. The layered composition of the atmosphere minimises the harmful effects of sunlight, ultraviolet radiation, the solar wind, and cosmic rays to protect organisms from genetic damage. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neotropical
The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropical terrestrial ecoregions of the Americas and the entire South American temperate zone. Definition In biogeography, the Neotropic or Neotropical realm is one of the eight terrestrial realms. This realm includes South America, Central America, the Caribbean islands, and southern North America. In Mexico, the Yucatán Peninsula and southern lowlands, and most of the east and west coastlines, including the southern tip of the Baja California Peninsula are Neotropical. In the United States southern Florida and coastal Central Florida are considered Neotropical. The realm also includes temperate southern South America. In contrast, the Neotropical Floristic Kingdom excludes southernmost South America, which instead is placed in the Antarctic kingdom. The Neotropic is delimited by similarities in fauna or flora. Its fauna and flora are distinct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Environment
The natural environment or natural world encompasses all life, living and non-living things occurring nature, naturally, meaning in this case not Artificiality, artificial. The term is most often applied to the Earth or some parts of Earth. This environment encompasses the interaction of all living species, climate, weather and natural resources that affect human survival and economic activity. The concept of the ''natural environment'' can be distinguished as components: * Complete ecological units that function as natural systems without massive civilized human intervention, including all vegetation, microorganisms, soil, Rock (geology), rocks, Atmosphere of Earth, atmosphere, and natural phenomenon, natural phenomena that occur within their boundaries and their nature. * Universal natural resources and physical phenomena that lack clear-cut boundaries, such as air, water, and climate, as well as energy, radiation, electric charge, and magnetism, not originating from civilize ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dual Polarization
Weather radar, also called weather surveillance radar (WSR) and Doppler weather radar, is a type of radar used to locate precipitation (meteorology), precipitation, calculate its motion, and estimate its type (rain, snow, hail etc.). Modern weather radars are mostly pulse-Doppler radars, capable of detecting the motion of rain droplets in addition to the intensity of the precipitation. Both types of data can be analyzed to determine the structure of storms and their potential to cause severe weather. During Radar in World War II, World War II, radar operators discovered that weather was causing echoes on their screen, masking potential enemy targets. Techniques were developed to filter them, but scientists began to study the phenomenon. Soon after the war, military surplus, surplus radars were used to detect precipitation. Since then, weather radar has evolved on its own and is now used by national weather services, research departments in universities, and in television station ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Relative Velocity
The relative velocity \vec_ (also \vec_ or \vec_) is the velocity of an object or observer B in the rest frame of another object or observer A. Classical mechanics In one dimension (non-relativistic) We begin with relative motion in the classical, (or non- relativistic, or the Newtonian approximation) that all speeds are much less than the speed of light. This limit is associated with the Galilean transformation. The figure shows a man on top of a train, at the back edge. At 1:00 pm he begins to walk forward at a walking speed of 10 km/h (kilometers per hour). The train is moving at 40 km/h. The figure depicts the man and train at two different times: first, when the journey began, and also one hour later at 2:00 pm. The figure suggests that the man is 50 km from the starting point after having traveled (by walking and by train) for one hour. This, by definition, is 50 km/h, which suggests that the prescription for calculating relative velocity in thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Doppler Shift
The Doppler effect or Doppler shift (or simply Doppler, when in context) is the change in frequency of a wave in relation to an observer who is moving relative to the wave source. It is named after the Austrian physicist Christian Doppler, who described the phenomenon in 1842. A common example of Doppler shift is the change of pitch heard when a vehicle sounding a horn approaches and recedes from an observer. Compared to the emitted frequency, the received frequency is higher during the approach, identical at the instant of passing by, and lower during the recession. The reason for the Doppler effect is that when the source of the waves is moving towards the observer, each successive wave crest is emitted from a position closer to the observer than the crest of the previous wave. Therefore, each wave takes slightly less time to reach the observer than the previous wave. Hence, the time between the arrivals of successive wave crests at the observer is reduced, causing an increa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar Cross-section
Radar cross-section (RCS), also called radar signature, is a measure of how detectable an object is by radar. A larger RCS indicates that an object is more easily detected. An object reflects a limited amount of radar energy back to the source. The factors that influence this include: *the material with which the target is made; *the size of the target relative to the wavelength of the illuminating radar signal; *the absolute size of the target; *the incident angle (angle at which the radar beam hits a particular portion of the target, which depends upon the shape of the target and its orientation to the radar source); *the reflected angle (angle at which the reflected beam leaves the part of the target hit; it depends upon incident angle); *the polarization of the transmitted and the received radiation with respect to the orientation of the target. While important in detecting targets, strength of emitter and distance are not factors that affect the calculation of an RCS becaus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reflectance
The reflectance of the surface of a material is its effectiveness in reflecting radiant energy. It is the fraction of incident electromagnetic power that is reflected at the boundary. Reflectance is a component of the response of the electronic structure of the material to the electromagnetic field of light, and is in general a function of the frequency, or wavelength, of the light, its polarization, and the angle of incidence. The dependence of reflectance on the wavelength is called a ''reflectance spectrum'' or ''spectral reflectance curve''. Mathematical definitions Hemispherical reflectance The ''hemispherical reflectance'' of a surface, denoted , is defined as R = \frac, where is the radiant flux ''reflected'' by that surface and is the radiant flux ''received'' by that surface. Spectral hemispherical reflectance The ''spectral hemispherical reflectance in frequency'' and ''spectral hemispherical reflectance in wavelength'' of a surface, denoted and respectively, are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clemson University
Clemson University () is a public land-grant research university in Clemson, South Carolina. Founded in 1889, Clemson is the second-largest university in the student population in South Carolina. For the fall 2019 semester, the university enrolled a total of 20,195 undergraduate students and 5,627 graduate students, and the student/faculty ratio was 18:1. Clemson's 1,400-acre campus is in the foothills of the Blue Ridge Mountains. The campus now borders Lake Hartwell, which was formed by the dam completed in 1962. The university manages the nearby 17,500-acre Clemson Experimental Forest that is used for research, education, and recreation. Clemson University consists of seven colleges: Agriculture, Forestry and Life Sciences; Architecture, Arts and Humanities; The Wilbur O. and Ann Powers College of Business; Behavioral, Social and Health Sciences; Education; Engineering, Computing and Applied Sciences; and Science. '' U.S. News & World Report'' ranks Clemson University 77th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WSR-57
WSR-57 radars were the USA's main weather surveillance radar for over 35 years. The National Weather Service operated a network of this model radar across the country, watching for severe weather. History The WSR-57 (Weather Surveillance Radar - 1957) was the first 'modern' weather radar. Initially commissioned at the Miami Hurricane Forecast Center, the WSR-57 was installed in other parts of the CONUS (continental United States). The WSR-57 was the first generation of radars designed expressly for a national warning network. The WSR-57 was designed in 1957 by Dewey Soltow using World War II technology. It gave only coarse reflectivity data and no velocity data, which made it extremely difficult to predict tornadoes. Weather systems were traced across the radar screen using grease pencils. Forecasters had to manually turn a crank to adjust the radar's scan elevation, and needed considerable skill to judge the intensity of storms based on green blotches on the radar scope. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Density
The density of air or atmospheric density, denoted '' ρ'', is the mass per unit volume of Earth's atmosphere. Air density, like air pressure, decreases with increasing altitude. It also changes with variation in atmospheric pressure, temperature and humidity. At 101.325 kPa (abs) and 20 °C (68 °F), air has a density of approximately , according to the International Standard Atmosphere (ISA). At 101.325kPa (abs) and , air has a density of approximately , which is about that of water, according to the International Standard Atmosphere (ISA). Pure liquid water is . Air density is a property used in many branches of science, engineering, and industry, including aeronautics;Olson, Wayne M. (2000) AFFTC-TIH-99-01, Aircraft Performance FlightICAO, Manual of the ICAO Standard Atmosphere (extended to 80 kilometres (262 500 feet)), Doc 7488-CD, Third Edition, 1993, .Grigorie, T.L., Dinca, L., Corcau J-I. and Grigorie, O. (2010) Aircrafts' Altitude Measurement Using Pressure Information:Ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
