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Advanced very-high-resolution radiometer

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74-563: The Advanced Very-High-Resolution Radiometer (AVHRR) instrument is a space-borne sensor that measures the reflectance of the Earth in five spectral bands that are relatively wide by today's standards. AVHRR instruments are or have been carried by the National Oceanic and Atmospheric Administration (NOAA) family of polar orbiting platforms ( POES ) and European MetOp satellites. The instrument scans several channels; two are centered on

148-443: A radiative transfer model that will convert observed MODIS scenes into those that a perfectly calibrated AVHRR would see. For MODIS/AVHRR SNO occurrences, it was determined that the ratio of AVHRR to MODIS radiances in both Ch1 and Ch2 are modeled well by a second-order polynomial of the radio of MODIS reflectances in channels 17 and 18. Channels 17 and 18 are located in a spectral region (0.94mm) sensitive to atmospheric water vapor,

222-405: A European MetImage instrument. [Television and Infrared Observation Satellite] National Oceanic and Atmospheric Administration The National Oceanic and Atmospheric Administration (abbreviated as NOAA / ˈ n oʊ . ə / NOH -ə ) is an American scientific and regulatory agency charged with forecasting weather , monitoring oceanic and atmospheric conditions, charting

296-469: A Libyan Desert target and Dome-C in Antarctica [Heidinger et al., 2010]. Ultimately, each individual calibration event available (MODIS/AVHRR SNO, Dome C, Libyan Desert, or AVHRR/AVHRR SNO) is used to provide a calibration slope time series for a given AVHRR sensor. Heidinger et al. [2010] use a second-order polynomial from a least-squares fit to determine the time series. The first step involves using

370-427: A climate point of view is the need for record continuity spanning 30+ years of three generations of AVHRR instruments as well as more contemporary sensors such as MODIS and VIIRS . Several artifacts may exist in the nominal AVHRR calibration, and even in updated calibrations, that cause a discontinuity in the long-term radiance record constructed from multiple satellites [Cao et al., 2008]. Brest and Rossow [1992], and

444-417: A daily basis. They issue more than 734,000 weather and 850,000 river forecasts, and more than 45,000 severe weather warnings annually. NOAA data is also relevant to the issues of climate change and ozone depletion . The NWS operates NEXRAD , a nationwide network of Doppler weather radars which can detect precipitation and their velocities. Many of their products are broadcast on NOAA Weather Radio ,

518-477: A filter to the original sensor observations and ultimately aggregated to produce a global, cloud free surface reflectance. After filtering, the global maps are segregated into monthly mean SURFACE, two bi-weekly SURFACE, and a mean TOTAL reflectance maps. The monthly mean SURFACE reflectance maps are used to detect long-term trends in calibration. The bi-weekly SURFACE maps are compared to each other and are used to detect short-term changes in calibration. Finally,

592-503: A function of solar zenith angle; calibrated NOAA-9 near-nadir reflectances are used to generate the curves that can then derive the calibrations for other AHVRRs in orbit (e.g. NOAA-11, -12, and -14). It was found that the ratio of calibration coefficients derived by Loeb [1997] and Rao and Chen [1995] are independent of solar zenith angle, thus implying that the NOAA-9-derived calibration curves provide an accurate relation between

666-502: A national drought early warning information system. The NOAA Commissioned Officer Corps is a uniformed service of men and women who operate NOAA ships and aircraft , and serve in scientific and administrative posts. Since 2001, the organization has hosted the senior staff and recent chair, Susan Solomon , of the Intergovernmental Panel on Climate Change 's working group on climate science. Hurricane Dorian

740-517: A network of radio transmitters that broadcasts weather forecasts, severe weather statements, watches and warnings 24 hours a day. The National Ocean Service (NOS) focuses on ensuring that ocean and coastal areas are safe, healthy, and productive. NOS scientists, natural resource managers, and specialists serve America by ensuring safe and efficient marine transportation, promoting innovative solutions to protect coastal communities, and conserving marine and coastal places. The National Ocean Service

814-553: A new agency to serve a national need for "better protection of life and property from natural hazards... for a better understanding of the total environment... [and] for exploration and development leading to the intelligent use of our marine resources". NOAA is a part of the Department of Commerce rather than the Department of Interior , because of a feud between President Nixon and his interior secretary, Wally Hickel , over

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888-522: A quantity that affects the accurate calibration of AVHRR Ch. 2. Using the Ch17 to Ch 18 ratio, an accurate guess at the total precipitable water (TPW) is obtained to further increase the accuracy of MODIS to AVHRR SNO calibrations. The Libyan Desert and Dome-C calibration sites are used when MODIS/AVHRR SNOs do not occur. Here, the AVHRR to MODIS ratio of reflectances is modeled as a third-order polynomial using

962-646: A research grants program through the Climate Program Office, and 13 cooperative institutes with academia. Through NOAA and its academic partners, thousands of scientists, engineers, technicians, and graduate students participate in furthering our knowledge of natural phenomena that affect the lives of us all. The Air Resources Laboratory (ARL) is one of the laboratories in the Office of Oceanic and Atmospheric Research. It studies processes and develops models relating to climate and air quality, including

1036-548: Is a modification of the flag of one of its predecessor organizations, the United States Coast and Geodetic Survey . The Coast and Geodetic Survey's flag, authorized in 1899 and in use until 1970, was blue, with a white circle centered in it and a red triangle centered within the circle. It symbolized the use of triangulation in surveying , and was flown by ships of the Survey. When NOAA was established in 1970 and

1110-890: 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

1184-610: Is composed of eight program offices: the Center for Operational Oceanographic Products and Services, the Office for Coastal Management, the National Centers for Coastal Ocean Science, the Office of Coast Survey , the Office of National Geodetic Survey , the Office of National Marine Sanctuaries , the Office of Ocean and Coastal Resource Management, and the Office of Response and Restoration . There are two NOS programs,

1258-716: Is home to over 40 NOAA sub-agencies and offices, including the National Weather Service . Richard (Rick) W. Spinrad is the 11th and current Under Secretary for Oceans and Atmosphere and NOAA Administrator. He was nominated by President Biden, and his nomination was confirmed by the US Senate on June 17, 2021, by voice vote. He was sworn in on June 23, 2021. From February 25, 2019, to January 20, 2021, Neil Jacobs , Assistant Secretary of Commerce for Environmental Observation and Prediction, served as acting Under Secretary of Commerce for Oceans and Atmosphere at

1332-598: Is led by a NOAA Corps two-star Rear Admiral , who also commands the NOAA Corps. The National Geodetic Survey (NGS) is a major surveying organization in the United States. The National Integrated Drought Information System is a program within NOAA with an interagency mandate to coordinate and integrate drought research, building upon existing federal, tribal, state, and local partnerships in support of creating

1406-547: Is part of NOAA's Office of Oceanic and Atmospheric Research, located in Miami , Florida . AOML's research spans hurricanes, coastal ecosystems, oceans, and human health, climate studies, global carbon systems, and ocean observations. AOML's organizational structure consists of an Office of the Director and three scientific research divisions, Physical Oceanography, Ocean Chemistry and Ecosystems, and Hurricane Research. The Office of

1480-470: Is that they lack the capability to perform accurate, onboard calibrations once on orbit [NOAA KLM]. Thus, post-launch on-orbit calibration activities (known as vicarious calibration methods) must be performed to update and ensure the accuracy of retrieved radiances and the subsequent products derived from these values [Xiong et al., 2010]. Numerous studies have been performed to update the calibration coefficients and provide more accurate retrievals versus using

1554-527: Is the annual update charts of the ongoing impact of changing conditions on the environment and community by NOAA. In 2019, it was compiled by 81 scientists from 12 nations. The Office of Marine and Aviation Operations is responsible for the fleet of NOAA ships, aircraft, and diving operations. It is the largest research fleet in the Federal government. Its personnel is made up of federal civil service employees and NOAA Corps Commissioned Officers . The office

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1628-651: The Birmingham, Alabama office of the National Weather Service issued a tweet that appeared to contradict Trump, saying that Alabama "will NOT see any impacts from Dorian". On September 6, NOAA published a statement from an unidentified spokesperson supporting Trump's September 1 claim. The statement also labelled the Birmingham, Alabama branch of the National Weather Service's contradiction of Trump as incorrect. The New York Times reported that

1702-824: The Landsat satellite system. Since May 1998, NESDIS has operated the Defense Meteorological Satellite Program (DMSP) satellites on behalf of the Air Force Weather Agency . New generations of satellites are developed to succeed the current polar orbiting and geosynchronous satellites, the Joint Polar Satellite System , and GOES-R , which launched in November 2016. NESDIS runs the Office of Projects, Planning, and Analysis (OPPA) formerly

1776-925: The Mussel Watch Contaminant Monitoring Program and the NOAA Integrated Ocean Observing System (IOOS). There are two staff offices, the International Program Office and the Management and Budget Office. The National Environmental Satellite, Data, and Information Service (NESDIS) was created by NOAA to operate and manage the US environmental satellite programs, and manage NWS data and those of other government agencies and departments. NESDIS's National Centers for Environmental Information (NCEI) archives data collected by

1850-571: The NOAA Commissioned Corps . Project 2025 has proposed to get rid of the Office of Oceanic and Atmospheric Research , which would "dismantle" NOAA's research division. Since 1993, NOAA's administrative headquarters has been located at the Silver Spring Metro Center office complex in downtown Silver Spring, Maryland . The consolidated 1.2 million SF, four-building campus was constructed in 1993 and

1924-723: The National Oceanic and Atmospheric Administration Fisheries Office of Law Enforcement in Silver Spring, Maryland , which is the primary site of marine resource law enforcement. NOAA's research, conducted through the Office of Oceanic and Atmospheric Research (OAR), is the driving force behind NOAA environmental products and services that protect life and property and promote economic growth. Research, conducted in OAR laboratories and by extramural programs, focuses on enhancing our understanding of environmental phenomena such as tornadoes, hurricanes, climate variability, solar flares, changes in

1998-608: The National Weather Service (NWS), the Office of Oceanic and Atmospheric Research (OAR) and the Office of Marine and Aviation Operations (OMAO). NOAA has more than a dozen staff offices, including the Office of the Federal Coordinator for Meteorology, the NOAA Central Library , the Office of Program Planning and Integration (PPI). The National Weather Service (NWS) is tasked with providing "weather, hydrologic and climate forecasts and warnings for

2072-742: The Visible Infrared Imaging Radiometer Suite , carried on the Joint Polar Satellite System spacecraft. NOAA has at least two polar-orbiting meteorological satellites in orbit at all times, with one satellite crossing the equator in the early morning and early evening and the other crossing the equator in the afternoon and late evening. The primary sensor on board both satellites is the AVHRR instrument. Morning-satellite data are most commonly used for land studies, while data from both satellites are used for atmosphere and ocean studies. Together they provide twice-daily global coverage, and ensure that data for any region of

2146-473: The nadir . Data from AVHRR (in its three evolutions) has been collected continuously since 1981. The primary purpose of these instruments is to monitor clouds and to measure the thermal emission of the Earth. These sensors have proven useful for a number of other applications, however, including the surveillance of land surfaces, ocean state, aerosols, etc. AVHRR data are particularly relevant to study climate change and environmental degradation because of

2220-409: The Birmingham, Alabama National Weather Service's contradiction of Trump. The second order came on September 4 after Trump displayed an August 29 map that was altered with a black marker to show that Hurricane Dorian may hit Alabama. On September 9, speaking at an Alabama National Weather Service (NWS) meeting the Director of the National Weather Service gave a speech supporting Birmingham NWS and said

2294-472: The Coast and Geodetic Survey's assets became a part of NOAA, NOAA based its own flag on that of the Coast and Geodetic Survey. The NOAA flag is, in essence, the Coast and Geodetic Survey flag, with the NOAA logo—a circle divided by the silhouette of a seabird into an upper dark blue and a lower light blue section, but with the "NOAA" legend omitted—centered within the red triangle. NOAA ships in commission display

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2368-680: The Director oversees the Laboratory's scientific programs, as well as its financial, administrative, computer, outreach/education, and facility management services. Research programs are augmented by the Cooperative Institute for Marine and Atmospheric Studies (CIMAS), a joint enterprise with the University of Miami's Rosenstiel School of Marine and Atmospheric Science. CIMAS enables AOML and university scientists to collaborate on research areas of mutual interest and facilitates

2442-557: The EUMETSAT Polar System (EPS) run by EUMETSAT , which will be succeeded by MetOp-SG . Remote sensing applications of the AVHRR sensor are based on validation (matchup) techniques of co-located ground observations and satellite observations. Alternatively, radiative transfer calculations are performed. There are specialized codes which allow simulation of the AVHRR observable brightness temperatures and radiances in near infrared and infrared channels. Prior to launch,

2516-483: The MODIS era is through direct AVHRR/AVHRR SNOs. Here, the counts from AVHRRs are plotted and a regression forced through the origin calculated. This regression is used to transfer the accurate calibration of one AVHRRs reflectances to the counts of an un-calibrated AVHRR and produce appropriate calibration slopes. These AVHRR/AVHRR SNOs do not provide an absolute calibration point themselves; rather they act as anchors for

2590-399: The MODIS observation is used to determine the sensor degradation and adjust the calibration accordingly. Methods for extending the calibration and record continuity also make use of similar calibration activities [Heidinger et al., 2010]. In the discussion thus far, methods have been posed that can calibrate individual or are limited to a few AVHRR sensors. However, one major challenge from

2664-579: The NOAA September 6 statement was prompted by a threat from U.S. Commerce Secretary Wilbur Ross to fire high-level NOAA staff unless they supported Trump's claim. The Department of Commerce described this report as "false". Meanwhile, The Washington Post reported that NOAA had twice ordered National Weather Service employees not to provide "any opinion" on Hurricane Dorian and to "only stick with official National Hurricane Center forecasts". The first order came after Trump's September 1 comments and

2738-553: The NOAA flag; those with only one mast fly it immediately beneath the ship's commissioning pennant or the personal flag of a civilian official or flag officer if one is aboard the ship, while multimasted vessels fly it at the masthead of the forwardmost mast. NOAA ships fly the same ensign as United States Navy ships but fly the NOAA flag as a distinguishing mark to differentiate themselves from Navy ships. Former: Moderate-resolution imaging spectroradiometer The Moderate Resolution Imaging Spectroradiometer ( MODIS )

2812-821: The NOAA, U.S. Navy , U.S. Air Force , the Federal Aviation Administration , and meteorological services around the world. It comprises the Center for Weather and Climate, previously NOAA's National Climatic Data Center , the National Coastal Data Development Center (NCDDC), the National Oceanographic Data Center (NODC), and the National Geophysical Data Center (NGDC)). In 1960, TIROS-1 , NASA's first owned and operated geostationary satellite,

2886-705: The Nixon Administration's Vietnam War policy. Nixon did not like Hickel's letter urging Nixon to listen to the Vietnam War demonstrators, and punished Hickel by not putting NOAA in the Interior Department. In 2007, NOAA celebrated 200 years of service in its role as successor to the U.S. Survey of the Coast . NOAA was officially formed in 1970. In 2021, NOAA had 11,833 civilian employees. Its research and operations are further supported by 321 uniformed service members, who make up

2960-772: The Office of Systems Development, the Office of Satellite Ground Systems (formerly the Office of Satellite Operations) the Office of Satellite and Project Operations, the Center for Satellite Applications and Research (STAR)], the Joint Polar Satellite System Program Office the GOES-R Program Office, the International & Interagency Affairs Office, the Office of Space Commerce and the Office of System Architecture and Advanced Planning. The National Marine Fisheries Service (NMFS), also known as NOAA Fisheries,

3034-712: The Republican conference that my friends don't want to fund programs that are not properly authorized," said Lucas. "NOAA is very important, so we need to get it authorized." NOAA works toward its mission through six major line offices: the National Environmental Satellite, Data, and Information Service (NESDIS), the National Marine Fisheries Service (NMFS), the National Ocean Service (NOS),

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3108-456: The TOTAL maps are used to detect and assess bias in the processing methodology. The target histograms are also examined, as changes in mode reflectances and in population are likely the result of changes in calibration. Long-term record continuity is achieved by the normalization between two sensors. First, observations from the operational time period overlap of two sensors are processed. Next,

3182-708: The US Department of Commerce and as NOAA's interim administrator. Jacobs succeeded Timothy Gallaudet , who succeeded Benjamin Friedman. The three served in series as NOAA's interim administrator throughout the first Trump Administration . In October 2017, Barry Lee Myers , CEO of AccuWeather , was proposed to be the agency's administrator by the Trump Administration. After two years in the nomination process, on November 21, 2019, Myers withdrew his name from consideration due to health concerns. NOAA

3256-434: The United States, its territories, adjacent waters and ocean areas, for the protection of life and property and the enhancement of the national economy", according to NOAA. This is done through a collection of national and regional centers, 13 river forecast centers (RFCs), and more than 120 local weather forecast offices (WFOs). They are charged with issuing weather and river forecasts , advisories, watches, and warnings on

3330-664: The absolute calibration of the AHVRR record makes use of the contemporary MODIS sensor onboard NASA's TERRA and AQUA satellites. The MODIS instrument has high calibration accuracy and can track its own radiometric changes due to the inclusion of an onboard calibration system for the VIS/NIR spectral region [MCST]. The following method utilizes the high accuracy of MODIS to absolutely calibrate AVHRRs via simultaneous nadir overpasses (SNOs) of both MODIS/AVHRR and AVHRR/AVHRR satellite pairs as well as MODIS-characterized surface reflectances for

3404-492: The calibration slope is made. An iterative method is then used to achieve the optimal slope values for Ch. 1 with slope corrections adjusting for uncertainties in ocean reflectance, water vapor, ozone, and noise. Ch. 2 is then subsequently calibrated under the condition that the stratus cloud optical thickness in both channels must be the same (spectrally uniform in the visible) if their calibrations are correct [Iwabuchi, 2003]. A more contemporary calibration method for AVHRR uses

3478-480: The comparatively long records of data already accumulated (over 20 years). The main difficulty associated with these investigations is to properly deal with the many limitations of these instruments, especially in the early period (sensor calibration, orbital drift, limited spectral and directional sampling, etc.). The AVHRR instrument also flies on the MetOp series of satellites. The three MetOp satellites are part of

3552-490: The detection and mapping of wildland fires in the United States. The United States Forest Service 's Remote Sensing Applications Center analyzes MODIS imagery on a continuous basis to provide information for the management and suppression of wildfires. MODIS utilizes four on-board calibrators in addition to the space view in order to provide in-flight calibration: solar diffuser (SD), solar diffuser stability monitor (SDSM), spectral radiometric calibration assembly (SRCA), and

3626-436: The earth are no more than six hours old. The swath width, the width of the area on the Earth's surface that the satellite can "see", is approximately 2,500 kilometers (~1,540 mi). The satellites orbit between 833 or 870 kilometers (+/− 19 kilometers, 516–541 miles) above the surface of the Earth. The highest ground resolution that can be obtained from the current AVHRR instruments is 1.1-kilometer (0.68 mi) per pixel at

3700-462: The highly accurate prelaunch calibration will degrade during launch and transit to orbit as well as during the operational life of the instrument [Molling et al., 2010]. Halthore et al. [2008] note that sensor degradation is mainly caused by thermal cycling, outgassing in the filters, damage from higher energy radiation (such as ultraviolet (UV)), and condensation of outgassed gases onto sensitive surfaces. One major design constraint of AVHRR instruments

3774-474: 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 MODIS characterization support team (MCST). With its high temporal resolution although low spatial resolution, MODIS data are useful to track changes in

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3848-465: The landscape over time. Examples of such applications are the monitoring of vegetation health by means of time-series analyses with vegetation indices, long term land cover changes (e.g. to monitor deforestation rates), global snow cover trends, water inundation from pluvial, riverine, or sea level rise flooding in coastal areas, change of water levels of major lakes such as the Aral Sea , and

3922-554: The natural logarithm of TWP from the NCEP reanalysis. Using these two methods, monthly calibration slopes are generated with a linear fit forced through the origin of the adjusted MODIS reflectances versus AVHRR counts. To extend the MODIS reference back for AVHRRs prior to the MODIS era (pre-2000), Heidinger et al. [2010] use the stable Earth targets of Dome C in Antarctica and the Libyan Desert. MODIS mean nadir reflectances over

3996-550: The on-orbit calibration capabilities of the VIS/IR channels of MODIS . Vermote and Saleous [2006] present a methodology that uses MODIS to characterize the BRDF of an invariant desert site. Due to differences in the spectral bands used for the instruments' channels, spectral translation equations were derived to accurately transfer the calibration accounting for these differences. Finally, the ratio of AVHRR observed to that modeled from

4070-432: The ozone, air pollution transport and dispersion , El Niño / La Niña events, fisheries productivity, ocean currents, deep sea thermal vents, and coastal ecosystem health. NOAA research also develops innovative technologies and observing systems. The NOAA Research network consists of seven internal research laboratories, extramural research at 30 Sea Grant university and research programs, six undersea research centers,

4144-792: The participation of students and visiting scientists. AOML is a member of a unique community of marine research and educational institutions located on Virginia Key in Miami, Florida. In 1977, the Pacific Marine Environmental Laboratory (PMEL) deployed the first successful moored equatorial current meter – the beginning of the Tropical Atmosphere Ocean , TAO, array. In 1984, the Tropical Ocean-Global Atmosphere program (TOGA) program began. The Arctic Report Card

4218-526: The pre-launch calibration. Rao and Chen [1995] use the Libyan Desert as a radiometrically stable calibration target to derive relative annual degradation rates for Channels 1 and 2 for AVHRR sensors on board the NOAA -7, -9, and -11 satellites. Additionally, with an aircraft field campaign over the White Sands desert site in New Mexico, USA [See Smith et al., 1988], an absolute calibration for NOAA-9

4292-478: The red (0.6 micrometres) and near- infrared (0.9 micrometres) regions, a third one is located around 3.5 micrometres, and another two the thermal radiation emitted by the planet, around 11 and 12 micrometres. The first AVHRR instrument was a four-channel radiometer . The last version, AVHRR/3, first carried on NOAA-15 launched in May 1998, acquires data in six channels. The AVHRR has been succeeded by

4366-473: The relative calibration between AVHRRs that can be used to transfer the ultimate MODIS calibration. Operational experience with the MODIS sensor onboard NASA's Terra and Aqua led to the development of AVHRR's follow-on, VIIRS . VIIRS is currently operating on board the Suomi NPP and NOAA-20 satellites. Whereas EUMETSAT MetOp satellites with AVHRR instruments will be succeeded by MetOp-SG satellites with

4440-482: The same calendar month [Rao and Chen, 1995], and any sensor degradation is corrected for by adjusting the slope (as a function of days after launch) between the albedo and digital count signal recorded [Rao and Chen, 1999]. In another similar method using surface targets, Loeb [1997] uses spatiotemporal uniform ice surfaces in Greenland and Antarctica to produce second-order polynomial reflectance calibration curves as

4514-508: The seas , conducting deep-sea exploration , and managing fishing and protection of marine mammals and endangered species in the US exclusive economic zone . The agency is part of the United States Department of Commerce and is headquartered in Silver Spring, Maryland . NOAA traces its history back to multiple agencies, some of which are among the earliest in the federal government: The most direct predecessor of NOAA

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4588-500: The solar zenith angle and observed reflectance over Greenland and Antarctica. Iwabuchi [2003] employed a method to calibrate NOAA-11 and -14 that uses clear-sky ocean and stratus cloud reflectance observations in a region of the NW Pacific Ocean and radiative transfer calculations of a theoretical molecular atmosphere to calibrate AVHRR Ch. 1. Using a month of clear-sky observations over the ocean, an initial minimum guess to

4662-454: The target are determined and are plotted versus the solar zenith angle. The counts for AVHRR observations at a given solar zenith angle and corresponding MODIS reflectance, corrected for TWP, are then used to determine what AVHRR value would be provided it had the MODIS calibration. The calibration slope is now calculated. One final method used by Heidinger et al. [2010] for extending the MODIS calibration back to AVHRRs that operated outside of

4736-405: The team "stopped public panic" and "ensured public safety". He said that when Birmingham issued their instructions they were not aware that the calls they were receiving were a result of Trump's tweet. The acting chief scientist and assistant administrator for the ocean and atmospheric research said he is "pursuing the potential violations" of the agency's scientific integrity policy. The NOAA flag

4810-521: The transport, dispersion , transformation and removal of pollutants from the ambient atmosphere. The emphasis of the ARL's work is on data interpretation, technology development and transfer. The specific goal of ARL research is to improve and eventually to institutionalize prediction of trends, dispersion of air pollutant plumes , air quality , atmospheric deposition, and related variables. The Atlantic Oceanographic and Meteorological Laboratory (AOML),

4884-428: The two global SURFACE maps are compared via a scatter plot. Additionally, observations are corrected for changes in solar zenith angle caused by orbital drift. Ultimately, a line is fit to determine the overall long-term drift in calibration, and, after a sensor is corrected for drift, normalization is performed on observations that occur during the same operational period [Brest et al., 1997]. Another recent method for

4958-536: The updated methodology [Brest et al., 1997], put forth a robust method for calibration monitoring of individual sensors and normalization of all sensors to a common standard. The International Satellite Cloud Climatology Project (ISCCP) method begins with the detection of clouds and corrections for ozone, Rayleigh scatter, and seasonal variations in irradiance to produce surface reflectances. Monthly histograms of surface reflectance are then produced for various surface types, and various histogram limits are then applied as

5032-447: The visible channels (Ch. 1 and 2) of AVHRR sensors are calibrated by the instrument manufacturer, ITT, Aerospace/Communications Division, and are traceable to NIST standards. The calibration relationship between electronic digital count response (C) of the sensor and the albedo (A) of the calibration target are linearly regressed: where S and I are the slope and intercept (respectively) of the calibration regression [NOAA KLM]. However,

5106-630: Was an extremely powerful and destructive tropical cyclone that devastated the northwestern Bahamas and caused significant damage to the Southeastern United States and Atlantic Canada in September 2019. By September 1, NOAA had issued a statement saying that the "current forecast path of Dorian does not include Alabama". However, on that date, President Donald Trump tweeted that Alabama, among other states, "will most likely be hit (much) harder than anticipated". Shortly thereafter,

5180-747: Was created by an executive order in 1970 and has never been established in law, despite its critical role. In January 2023, The Washington Post reported that Congressman Frank Lucas , the new chair of the House Science, Space and Technology Committee, had released draft legislation to make NOAA an independent agency, rather than it being part of the Commerce Department. Lucas' push was in response to Republican leaders who had signaled plans to slash funding for agencies and programs that continued to receive annual appropriations, but had not been reauthorized by Congress. "It's been made quite clear in

5254-451: Was initiated in 1871 with a primary goal of the research, protection, management, and restoration of commercial and recreational fisheries and their habitat, and protected species. The NMFS operates twelve headquarters offices, five regional offices, six fisheries science centers, and more than 20 laboratories throughout the United States and U.S. territories, which are the sites of research and management of marine resources. The NMFS operates

5328-401: Was launched. Since 1966, NESDIS has managed polar orbiting satellites (POES). Since 1974, it has operated geosynchronous satellites (GOES). In 1979, NOAA's first polar-orbiting environmental satellite was launched. Current operational satellites include NOAA-15 , NOAA-18 , NOAA-19 , GOES 13 , GOES 14 , GOES 15 , Jason-2 and DSCOVR . In 1983, NOAA assumed operational responsibility for

5402-658: Was the Environmental Science Services Administration (ESSA), into which several existing scientific agencies such as the United States Coast and Geodetic Survey , the Weather Bureau and the uniformed Corps were absorbed in 1965. NOAA was established within the Department of Commerce via the Reorganization Plan No. 4, and formed on October 3, 1970, after U.S. President Richard Nixon proposed creating

5476-471: Was transferred from a well calibrated spectrometer on board a U-2 aircraft flying at an altitude of ~18 km in a congruent path with the NOAA-9 satellite above. After being corrected for the relative degradation, the absolute calibration of NOAA-9 is then passed onto NOAA −7 and −11 via a linear relationship using Libyan Desert observations that are restricted to similar viewing geometries as well as dates in

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