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MODIS
The Moderate Resolution Imaging Spectroradiometer (MODIS) is a satellite-based sensor used for earth and climate measurements. There are two MODIS sensors in Earth orbit: one on board the Terra (EOS AM) satellite, launched by NASA in 1999; and one on board the Aqua (EOS PM) satellite, launched in 2002. MODIS has now been replaced by the VIIRS, which first launched in 2011 aboard the Suomi NPP satellite. The MODIS instruments were built by Santa Barbara Remote Sensing. They capture data in 36 spectral bands ranging in wavelength from 0.4 μm to 14.4 μm and at varying spatial resolutions (2 bands at 250 m, 5 bands at 500 m and 29 bands at 1 km). Together the instruments image the entire Earth every 1 to 2 days. They are designed to provide measurements in large-scale global dynamics including changes in Earth's cloud cover, radiation budget and processes occurring in the oceans, on land, and in the lower atmosphere. Support and calibration is provided by the MO ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modis Image Of California Wildfires Taken On October 22, 2007
The Moderate Resolution Imaging Spectroradiometer (MODIS) is a satellite-based sensor used for earth and climate measurements. There are two MODIS sensors in Earth orbit: one on board the Terra (EOS AM) satellite, launched by NASA in 1999; and one on board the Aqua (EOS PM) satellite, launched in 2002. MODIS has now been replaced by the VIIRS, which first launched in 2011 aboard the Suomi NPP satellite. The MODIS instruments were built by Santa Barbara Remote Sensing. They capture data in 36 spectral bands ranging in wavelength from 0.4 μm to 14.4 μm and at varying spatial resolutions (2 bands at 250 m, 5 bands at 500 m and 29 bands at 1 km). Together the instruments image the entire Earth every 1 to 2 days. They are designed to provide measurements in large-scale global dynamics including changes in Earth's cloud cover, radiation budget and processes occurring in the oceans, on land, and in the lower atmosphere. Support and calibration is provided by the MOD ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MODIS ATM Solar Irradiance
The Moderate Resolution Imaging Spectroradiometer (MODIS) is a satellite-based sensor used for earth and climate measurements. There are two MODIS sensors in Earth orbit: one on board the Terra (EOS AM) satellite, launched by NASA in 1999; and one on board the Aqua (EOS PM) satellite, launched in 2002. MODIS has now been replaced by the VIIRS, which first launched in 2011 aboard the Suomi NPP satellite. The MODIS instruments were built by Santa Barbara Remote Sensing. They capture data in 36 spectral bands ranging in wavelength from 0.4 μm to 14.4 μm and at varying spatial resolutions (2 bands at 250 m, 5 bands at 500 m and 29 bands at 1 km). Together the instruments image the entire Earth every 1 to 2 days. They are designed to provide measurements in large-scale global dynamics including changes in Earth's cloud cover, radiation budget and processes occurring in the oceans, on land, and in the lower atmosphere. Support and calibration is provided by the MOD ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ocean Color
Ocean color is the branch of ocean optics that specifically studies the color of the water and information that can be gained from looking at variations in color. The color of the ocean, while mainly blue, actually varies from blue to green or even yellow, brown or red in some cases. This field of study developed alongside water remote sensing, so it is focused mainly on how color is measured by instruments (like the sensors on satellites and airplanes). Most of the ocean is blue in color, but in some places the ocean is blue-green, green, or even yellow to brown. Blue ocean color is a result of several factors. First, water preferentially absorbs red light, which means that blue light remains and is reflected back out of the water. Red light is most easily absorbed and thus does not reach great depths, usually to less than 50 meters (164 ft.). Blue light, in comparison, can penetrate up to 200 meters (656 ft.). Second, water molecules and very tiny particles in ocean w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth Observing System
The Earth Observing System (EOS) is a program of NASA comprising a series of artificial satellite missions and scientific instruments in Earth orbit designed for long-term global observations of the land surface, biosphere, atmosphere, and oceans. Since the early 1970s, NASA has been developing its Earth Observing System, launching a series of LANDSAT satellites in the decade. Some of the first included Passive-Microwave imaging in 1972 through the Nimbus 5 Satellite. Following the launch of various satellite missions, the conception of the program began in the late 80s and expanded rapidly through the 90s. Since the inception of the program, it has continued to develop to what we can collect in data today, including; land, sea, radiation and atmosphere. Collected in a system known as EOSDIS, NASA uses this data in order to study the progression and changes in the biosphere of Earth. The main focus of this data collection surrounds climatic science. The program is the centrepiece o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wildland Fires
A wildfire, forest fire, bushfire, wildland fire or rural fire is an unplanned, uncontrolled and unpredictable fire in an area of Combustibility and flammability, combustible vegetation. Depending on the type of vegetation present, a wildfire may be more specifically identified as a bushfire(bushfires in Australia, in Australia), desert fire, grass fire, hill fire, peat fire, prairie fire, vegetation fire, or veld fire. Fire ecology, Some natural forest ecosystems depend on wildfire. Wildfires are distinct from beneficial human usage of wildland fire, called controlled burn, controlled burning, although controlled burns can turn into wildfires. Fossil charcoal indicates that wildfires began soon after the appearance of terrestrial plants approximately 419 million years ago during the Silurian period. Earth's carbon-rich vegetation, seasonally dry climates, atmospheric oxygen, and widespread lightning and volcanic ignitions create favorable conditions for fires. The occurre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albedo
Albedo (; ) is the measure of the diffuse reflection of sunlight, solar radiation out of the total solar radiation and measured on a scale from 0, corresponding to a black body that absorbs all incident radiation, to 1, corresponding to a body that reflects all incident radiation. Surface albedo is defined as the ratio of Radiosity (radiometry), radiosity ''J''e to the irradiance ''E''e (flux per unit area) received by a surface. The proportion reflected is not only determined by properties of the surface itself, but also by the spectral and angular distribution of solar radiation reaching the Earth's surface. These factors vary with atmospheric composition, geographic location, and time (see position of the Sun). While bi-hemispherical reflectance is calculated for a single angle of incidence (i.e., for a given position of the Sun), albedo is the directional integration of reflectance over all solar angles in a given period. The temporal resolution may range from seconds (as ob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenology
Phenology is the study of periodic events in biological life cycles and how these are influenced by seasonality, seasonal and interannual variations in climate, as well as environmental factor, habitat factors (such as elevation). Examples include the date of emergence of leaves and flowers, the first flight of butterflies, the first appearance of bird migration, migratory birds, the date of leaf colouring and fall in deciduous trees, the dates of egg-laying of birds and amphibia, or the timing of the developmental cycles of temperate-zone honey bee colonies. In the scientific literature on ecology, the term is used more generally to indicate the time frame for any seasonal biological phenomena, including the dates of last appearance (e.g., the seasonal phenology of a species may be from April through September). Because many such phenomena are very sensitive to small variations in climate, especially to temperature, phenological records can be a useful proxy (climate), proxy for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terra (satellite)
Terra (EOS AM-1) is a multi-national, NASA scientific research satellite in a Sun-synchronous orbit around the Earth that takes simultaneous measurements of Earth's atmosphere, land, and water to understand how Earth is changing and to identify the consequences for life on Earth. It is the flagship of the Earth Observing System (EOS) and the first satellite of the system which was followed by Aqua (launched in 2002) and Aura (launched in 2004). Terra was launched in 1999. The name "Terra" comes from the Latin word for Earth. A naming contest was held by NASA among U.S. high school students. The winning essay was submitted by Sasha Jones of Brentwood, Missouri. The identifier "AM-1" refers to its orbit, passing over the equator in the morning. Launch The satellite was launched from Vandenberg Air Force Base on December 18th, 1999, aboard an Atlas IIAS vehicle and began collecting data on February 24th, 2000. It was placed into a near-polar, sun-synchronous orbit at a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aqua (satellite)
Aqua (EOS PM-1) is a NASA scientific research satellite in orbit around the Earth, studying the precipitation, evaporation, and cycling of water. It is the second major component of the Earth Observing System (EOS) preceded by Terra (launched 1999) and followed by Aura (launched 2004). The name "Aqua" comes from the Latin word for water. The satellite was launched from Vandenberg Air Force Base on May 4, 2002, aboard a Delta II rocket. Aqua operated in a sun-synchronous orbit as the third in the satellite formation called the " A Train" with several other satellites (OCO-2, the Japanese GCOM W1, PARASOL, CALIPSO, CloudSat, and Aura) for most of its first 20 years; but in January 2022 Aqua left the A-Train (as CloudSat, CALIPSO and PARASOL had already done) when, due to its fuel limitations, it transitioned to a free-drift mode, wherein its equatorial crossing time is slowly drifting to later times, from its tightly controlled orbit. Mission Aqua is one of NASA's missions for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VIIRS
The Visible Infrared Imaging Radiometer Suite (VIIRS) is a sensor designed and manufactured by the Raytheon Company on board the polar-orbiting Suomi National Polar-orbiting Partnership (Suomi NPP), NOAA-20, and NOAA-21 weather satellites. VIIRS is one of five key instruments onboard Suomi NPP, launched on October 28, 2011. VIIRS is a whiskbroom scanner radiometer that collects imagery and radiometric measurements of the land, atmosphere, cryosphere, and oceans in the Visible spectrum, visible and infrared bands of the electromagnetic spectrum. VIIRS is capable of generating two data processing streams that result in two different sets of land products, with global coverage every 14 hours. One is produced by NOAA, and provides operational data for use by the National Weather Service. These are known as environmental data records (EDRs). The other stream is from NASA, and is intended to contribute to the larger scientific community. These are known as Earth System Data Records (E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cloud Cover
Cloud cover (also known as cloudiness, cloudage, or cloud amount) refers to the fraction of the sky obscured by clouds on average when observed from a particular location. Okta is the usual unit for measurement of the cloud cover. The cloud cover is correlated to the sunshine duration as the least cloudy locales are the sunniest ones while the cloudiest areas are the least sunny places, as clouds can block sunlight, especially on sunrise and sunset where sunlight is already limited. The global cloud cover averages around 0.68 when analyzing clouds with optical depth larger than 0.1. This value is lower (0.56) when considering clouds with an optical depth larger than 2, and higher when counting subvisible cirrus clouds. Particularly over the oceans cloud cover is persistent with an average 72% of cloud cover. Role in the climate system Clouds play multiple critical roles in the climate system and diurnal cycle. In particular, being bright objects in the visible part o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bidirectional Reflectance Distribution Function
The bidirectional reflectance distribution function (BRDF; f_(\omega_,\, \omega_) ) is a function of four real variables that defines how light is reflected at an opaque surface. It is employed in the optics of real-world light, in computer graphics algorithms, and in computer vision algorithms. The function takes an incoming light direction, \omega_, and outgoing direction, \omega_ (taken in a coordinate system where the surface normal \mathbf n lies along the ''z''-axis), and returns the ratio of reflected radiance exiting along \omega_ to the irradiance incident on the surface from direction \omega_. Each direction \omega is itself parameterized by azimuth angle \phi and zenith angle \theta, therefore the BRDF as a whole is a function of 4 variables. The BRDF has units sr−1, with steradians (sr) being a unit of solid angle. Definition The BRDF was first defined by Fred Nicodemus around 1965. The definition is: f_(\omega_,\, \omega_) \,=\, \frac \,=\, \frac\frac wher ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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