The NASA Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) focused on factors impacting changes in Arctic climate, atmospheric composition, and radiative characteristics, including mid-latitude pollution, boreal forest fires, aerosol radiative forcing, and chemical processes. ARCTAS had three deployments over Alaska, Western Canada, and California during the boreal spring and summer of 2008. Airborne observations were made of several chemical constituents and aerosol properties. ARCTAS was supported by NASA’s Tropospheric Chemistry and Radiation Science programs.
The High Spectral Resolution Lidar (HSRL) is an airborne lidar system developed at NASA Langley Research Center (LaRC). It utilizes the HSRL technique at 532 nm and the standard backscatter technique at 1064 nm to provide profile measurements of aerosol backscatter, extinction, and depolarization. The profiles of aerosol backscatter and depolarization have a typical vertical resolution of 30 m and a horizontal resolution of about 1 km. For the extinction profiles, the vertical resolution is 300 m with a horizontal resolution of about 6 km. HSRL is typically flown on investigations to validate observations from the CALIPSO spaceborne lidar.
Earth Science > Spectral/engineering > Lidar > Lidar Depolarization Ratio
The Research Scanning Polarimeter (RSP) is an airborne, passive polarimeter developed by SpecTIR Corporation. It measures total radiance and linear polarization across 9 spectral bands in the visible and infrared wavelengths (410-2250 nm). These measurements can be used to derive aerosol and cloud properties. RSP has a time resolution of 0.8 seconds, a field of view of 14 mrad, and a horizontal resolution of about 100 m at an altitude of 5 km.
The Airborne Tunable Laser Absorption Spectrometer (ATLAS) is an in situ airborne spectrometer developed by NASA. ATLAS utilizes second-harmonic absorption spectrometry to measure trace gases in the lower stratosphere such as nitrous oxide, methane, carbon monoxide, and ozone. The laser within ATLAS is tuned to the infrared absorption band of the target gas and is frequency modulated at 2 kHz with the second-harmonic detection occurring at 4 kHz. ATLAS provides measurements at a time resolution of 1 s and has a spatial resolution of about 200 m when deployed on the ER-2 aircraft.
If instrument name or model is not available but documents show that specific chemical compounds or constituents or their properties were observed, can use instrument entry. Examples include: CO, CO2, NO, NO2, N2O, HNO3, HNO4, OH, H2SO4, CH3CN, O3, H2O, halocarbons, VOCs, nitrates, aerosols (including CCN), aerosol optical properties, etc...
Earth Science > >
The Aerosol Mass Spectrometer (AMS) is a spectrometer that measures the chemical composition and properties of sub-micron aerosol particles. AMS has a maximum data collection of 100 Hz and can detect particles with a size range of 40 nm to 1 micron. It operates by switching between mass spectrum (MS) mode and particle time-of-flight (PToF) mode to determine the chemical makeup of aerosol samples. The AMS can be deployed on aircraft, ships, mobile laboratories, or placed directly at a field site.
Earth Science > Atmosphere > Aerosols > Chemical Composition
The Optical Particle Counter is an instrument based on the principle of light scattering from particles. It is a real time instrument that is typically used to measure particles above 0.05 μm in diameter.
If instrument mode or detailed specification information is not available, can use this entry for spectrometers of various types. A spectrometer is an instrument that measures a range of a characteristic for a given substance or wavelength. There are many different types of spectrometers. Some examples are mass spectrometers, spectrophotometers, and magnetic radiation spectrometers.
The Cloud Absorption Radiometer (CAR) is an airborne multi-wavelength scanning radiometer developed by Goddard Space Flight Center (GSFC). CAR provides measurements of scattered radiance and bidirectional reflectance of the surface across 14 spectral bands in the visible and near-infrared wavelengths (0.34-2.30 µm). It also acquires imagery of cloud and Earth surface features. CAR has a scan rate of 1.67 Hz (100 rpm) and has a spatial resolution of 4m at nadir for an altitude of 200m above ground level.
Earth Science > Atmosphere > Clouds > Cloud Radiative Transfer
The Single Particle Soot Photometer (SP2) is a laser-induced photometer manufactured by Droplet Measurement Technologies. SP2 provides measurements of the black carbon (BC) mass content of individual aerosol particles as well as the optical and physical properties of the particles containing BC. SP2 can be utilized on airborne or ground-based platforms and can be deployed with a paired Humidified-Dual SP2 (HD-SP2). It can detect aerosol particles with a diameter size of 200-400 nm and can measure 25,000 particles/second.
Broadband Radiometers (BBR) are modified versions of the Kipp & Zonen CM-22 pyranometers and CG-4 pyrgeometers. They have been modified to be more suitable for airborne platforms through different instrument housing and signal amplification. BBR measures solar irradiance in the 0.2-3.6 μm wavelength range and infrared (IR) irradiance in the 4.5-42 μm range. These measurements can be used to derive net irradiance, radiative forcing, absorption, and albedo. It has a typical sampling rate of 1 Hz and a hemispheric field-of-view.
Earth Science > Atmosphere > Atmospheric Radiation > Solar Irradiance
The Condensation Nuclei Counter (CNC) is optical method for
counting atmospheric aerosol particles.
Earth Science > >
The Airborne Tracking Sun Photometer (ATSP) is an airborne instrument that measures direct solar beam transmission. The ATSP measures solar beam transmission through multiple channels with wavelengths ranging between 354 and 2139 nm. These measurements can be used to derive aerosol optical depth and other aerosol properties. There are multiple versions of this instrument, including one developed by the NASA Ames Research Center.
The Particle Soot Absorption Photometer (PSAP) is an in situ airborne photometer manufactured by Radiance Research. It uses Beer's Law to measure the change in light transmission of aerosol particles. These measurements can be used to derive aerosol absorption and extinction. PSAP operates across three wavelengths (467, 530, and 660 nm) and has a temporal resolution of 1 second. It is typically deployed on aircraft, but it can be deployed on other platforms such as ships and vehicles.
The Tandem Differential Mobility Analyzer (TDMA) is an in situ airborne and ground-based analyzer that measures the physical properties of aerosol particles such as size distribution and concentration. It can measure particles in the size range of 0.013 to 0.75 mm at a size resolution of 0.013 mm at 0.2 mm. The TDMA is sometimes combined with an Aerodynamic Particle Sizer (APS) to allow measurements of particles in the submicron range. A typical measurement sequence of TDMA can take approximately 45 minutes to complete.
Nephelometers are in situ airborne or ground-based optical sensors. They measure the total scattering and backscattering of aerosol particles in the atmosphere. Nephelometers operate across three wavelengths: 450 nm, 550 nm, and 700 nm, and have a typical time resolution of 1 Hz.
Measurements of Atmospheric Carbon Dioxide Over Northwestern North America is a differential, non-dispersive, infrared (NDIR) gas analyzer. The CO2 measurements are based on the difference in absorption of infrared(IR) radiation passing through two gas sampling cells. The reference cell is used for a gas of known CO2 concentration, and the sample cell is used for agas of unknown concentration. Infrared radiation is transmitted through both cell paths, and the output of the analyzer is proportional to the difference in absorption between the two.
The Particle Into Liquid Sampler (PILS) is an in situ aerosol sampler manufactured by Brechtel Manufacturing Inc. PILS can be utilized by both ground-based and airborne platforms to collect continuous measurements of ambient aerosol bulk composition. The particles sampled by PILS are mixed with saturated water vapor to produce droplets that are analyzed by either an ion chromatograph (IC) or a total organic carbon detector (TOC). PILS can measure aerosol particles with a size range of 70 nm to 2.5 μm and has a time resolution of 3 min for airborne measurements and 15 min for ground-based.
Earth Science > Atmosphere > Aerosols > Chemical Composition
The HR-AMS is an upgraded version of Aerodyne’s AMS instrument. HR-AMS has a high spatial resolution and a time-of-flight measurement technique. HR-AMS is a mass spectrometer that measures aerosols in the troposphere.
The GC-MS instrument is a combination of two instruments: a gas chromatograph and a mass spectrometer. It is used on airborne platforms to study atmospheric chemistry, specifically non-methane halocarbons and volatile organic compounds.
If instrument name or model is not available but documents show that specific chemical compounds or constituents or their properties were observed, can use instrument entry. Examples include: CO, CO2, NO, NO2, N2O, HNO3, HNO4, OH, H2SO4, CH3CN, O3, H2O, halocarbons, VOCs, nitrates, aerosols (including CCN), aerosol optical properties, etc...
Earth Science > >
The Georgia Institute of Technology Chemical Ionization Mass Spectrometer (GT-CIMS) is an in situ airborne spectrometer. It uses a lower-pressure flow tube reactor to measure reactive nitrogen species such as nitric acid and peroxyacetyl nitrate (PAN) in the lower atmosphere. GT-CIMS has a typical temporal resolution of 1 second and a detection limit of 10 pptv.
The Thermal-Dissociation Laser Induced Fluorescence (TD-LIF) is an in situ airborne sensor developed at UC Berkeley. It uses a combination of the TD and LIF techniques to measure nitrogen dioxide (NO2), peroxynitrates, nitric acid (HNO3), and other stable organic nitrates in the atmosphere. TD-LIF operates at the 585 nm wavelength and has a typical measurement frequency of 1 Hz.
The Proton Transfer Mass Spectrometer (PTR-MS) is an in situ airborne and ground-based spectrometer designed by the University of Innsbruck in Austria. It measures volatile organic compounds (VOCs) without sample preparation at very low concentrations. PTR-MS uses chemical ionization mass spectroscopy allowing for fast and highly sensitive detection of VOCs. It has a 0.5 to 1 s signal integration time.
Aethalometer is an in situ aerosol instrument manufactured by Magee Scientific that can be deployed on either airborne or ground-based platforms. It samples aerosols through a filter tape and measures the attenuation of transmitted light to determine the concentration of black carbon particles. The Aethalometer operates across seven optical wavelengths (370, 470, 520, 590, 660, 880, and 950 nm) and can provide data at a rate of 1 Hz. It has a measurement range of 0-500 μg per cubic meter and a resolution of 0.1 μg per cubic meter.
If instrument mode or detailed specification information is not available, can use this entry for spectrometers of various types. A spectrometer is an instrument that measures a range of a characteristic for a given substance or wavelength. There are many different types of spectrometers. Some examples are mass spectrometers, spectrophotometers, and magnetic radiation spectrometers.
A TUNABLE DIODE LASER is a solid-state laser in which as lasing is achieved by passing an injection current through the active region of a semiconductor across the p-n junction; tunable meaning it is used with a technique based upon the measurement of light absorption upon irrigating a sample using a tunable laser source.
The Single Particle Soot Photometer (SP2) is a laser-induced photometer manufactured by Droplet Measurement Technologies. SP2 provides measurements of the black carbon (BC) mass content of individual aerosol particles as well as the optical and physical properties of the particles containing BC. SP2 can be utilized on airborne or ground-based platforms and can be deployed with a paired Humidified-Dual SP2 (HD-SP2). It can detect aerosol particles with a diameter size of 200-400 nm and can measure 25,000 particles/second.
The Airborne Tropospheric Hydrogen Oxides Sensor (ATHOS) is an in situ airborne sensor developed by Penn State University. ATHOS uses a laser-induced fluorescence (LIF) technique to measure hydroxide (OH) and hydroperoxyl (HO2) in the atmosphere. ATHOS operates near the 308 nm wavelength, has a pulse repetition frequency of 3 kHz, and has a typical time resolution of 20-30 s. It was designed to be equipped on NASA’s DC-8 aircraft and can collect measurements of OH and HO2 in clear sky and light cloud conditions.
The CalTech Chemical Ionization Mass Spectrometer (CIT-CIMS) is an in situ airborne single mass spectrometer. CIT-CIMS utilizes CF3O-ion chemistry and compact time-of-flight and triple quadrupole spectrometers to measure specific atmospheric trace gases such as nitric acid, hydrogen peroxide, and sulfur dioxide. It was designed with rapid scan capabilities, allowing it to operate at a high temporal resolution (10 Hz) and detect a wide mass range. CIT-CIMS is typically used for airborne observations, but it can be used for ground-based observations as well.
The Differential Absorption Lidar (DIAL) is an airborne lidar system designed at NASA’s Langley Research Center (LaRC). It uses four lasers to detect lidar backscatter to provide profile measurements of ozone and aerosols in the atmosphere. DIAL operates in the ultraviolet (289-300 nm) for ozone measurements and operates in the visible (572-600 nm) and infrared (1064 nm) for aerosols. It has a horizontal spatial resolution of approximately 15 km and has a measurement accuracy of 5 ppbv.
Earth Science > Spectral/engineering > Lidar > Lidar Depolarization Ratio
The Whole Air Sampler (WAS) is an airborne in-situ instrument that collects samples of air for analysis of trace gases, such as nonmethane hydrocarbons (NMHCs), Halocarbons, Alkyl Nitrates, and various sulfur compounds that are present in the troposphere. Air samples collected via the WAS then undergo gas chromatography and mass spectrometry to determine which gasses are present in the sample. The WAS collects samples every minute, which enables scientists to get a clear picture of the chemical composition of the environment as research aircraft pass through.
The Condensation Nuclei Counter (CNC) is optical method for
counting atmospheric aerosol particles.
Earth Science > >
Nephelometers are in situ airborne or ground-based optical sensors. They measure the total scattering and backscattering of aerosol particles in the atmosphere. Nephelometers operate across three wavelengths: 450 nm, 550 nm, and 700 nm, and have a typical time resolution of 1 Hz.
Multi Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) in the atmosphere is a novel measurement technique that represents a significant advance on the well-established zenith scattered sunlight DOAS instruments which are mainly sensitive to stratospheric absorbers. MAX-DOAS instruments are basically a combination of UV/visible spectrometers observing scattered light in different viewing directions. MAX-DOAS utilizes scattered sunlight received from multiple viewing directions. The spatial distribution of various trace gases close to the instrument can be derived by combining several viewing directions. Ground based MAX-DOAS is highly sensitive to absorbers in the lowest few kilometres of the atmosphere and vertical profile information can be retrieved by combining the measurements with Radiative Transfer Model (RTM) calculations.
The AErosol RObotic NETwork (AERONET) is a federated network of ground-based remote sensing aerosol sensors established by NASA and the PHOtométrie pour le Traitement Opérationnel de Normalisation Satellitaire (PHOTONS) in 1993. Each AERONET site consists of a CIMEL Electronique sunphotometer that provides measurements of sun irradiance and sky radiances. These measurements can be used to retrieve aerosol properties such as aerosol optical depth and extinction. The sunphotometers operate across nine wavelengths (340, 380, 440, 500, 675, 870, 937, 1020, and 1640 nm) and provide aerosol measurements approximately every 15 min. AERONET sites are located across the world, making it possible to map around 90% of the Earth’s surface.
Lidar is a surveying method that measures distance to a target by illuminating the target with laser light and measuring the reflected light with a sensor. Differences in laser return times and wavelengths can then be used to make digital 3-D representations of the target.
Earth Science > >
Multi Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) in the atmosphere is a novel measurement technique that represents a significant advance on the well-established zenith scattered sunlight DOAS instruments which are mainly sensitive to stratospheric absorbers. MAX-DOAS instruments are basically a combination of UV/visible spectrometers observing scattered light in different viewing directions. MAX-DOAS utilizes scattered sunlight received from multiple viewing directions. The spatial distribution of various trace gases close to the instrument can be derived by combining several viewing directions. Ground based MAX-DOAS is highly sensitive to absorbers in the lowest few kilometres of the atmosphere and vertical profile information can be retrieved by combining the measurements with Radiative Transfer Model (RTM) calculations.
The AErosol RObotic NETwork (AERONET) is a federated network of ground-based remote sensing aerosol sensors established by NASA and the PHOtométrie pour le Traitement Opérationnel de Normalisation Satellitaire (PHOTONS) in 1993. Each AERONET site consists of a CIMEL Electronique sunphotometer that provides measurements of sun irradiance and sky radiances. These measurements can be used to retrieve aerosol properties such as aerosol optical depth and extinction. The sunphotometers operate across nine wavelengths (340, 380, 440, 500, 675, 870, 937, 1020, and 1640 nm) and provide aerosol measurements approximately every 15 min. AERONET sites are located across the world, making it possible to map around 90% of the Earth’s surface.
Measurements of Atmospheric Carbon Dioxide Over Northwestern North America is a differential, non-dispersive, infrared (NDIR) gas analyzer. The CO2 measurements are based on the difference in absorption of infrared(IR) radiation passing through two gas sampling cells. The reference cell is used for a gas of known CO2 concentration, and the sample cell is used for agas of unknown concentration. Infrared radiation is transmitted through both cell paths, and the output of the analyzer is proportional to the difference in absorption between the two.
The Particle Into Liquid Sampler (PILS) is an in situ aerosol sampler manufactured by Brechtel Manufacturing Inc. PILS can be utilized by both ground-based and airborne platforms to collect continuous measurements of ambient aerosol bulk composition. The particles sampled by PILS are mixed with saturated water vapor to produce droplets that are analyzed by either an ion chromatograph (IC) or a total organic carbon detector (TOC). PILS can measure aerosol particles with a size range of 70 nm to 2.5 μm and has a time resolution of 3 min for airborne measurements and 15 min for ground-based.
Earth Science > Atmosphere > Aerosols > Chemical Composition
The HR-AMS is an upgraded version of Aerodyne’s AMS instrument. HR-AMS has a high spatial resolution and a time-of-flight measurement technique. HR-AMS is a mass spectrometer that measures aerosols in the troposphere.
The GC-MS instrument is a combination of two instruments: a gas chromatograph and a mass spectrometer. It is used on airborne platforms to study atmospheric chemistry, specifically non-methane halocarbons and volatile organic compounds.
If instrument name or model is not available but documents show that specific chemical compounds or constituents or their properties were observed, can use instrument entry. Examples include: CO, CO2, NO, NO2, N2O, HNO3, HNO4, OH, H2SO4, CH3CN, O3, H2O, halocarbons, VOCs, nitrates, aerosols (including CCN), aerosol optical properties, etc...
Earth Science > >
The Georgia Institute of Technology Chemical Ionization Mass Spectrometer (GT-CIMS) is an in situ airborne spectrometer. It uses a lower-pressure flow tube reactor to measure reactive nitrogen species such as nitric acid and peroxyacetyl nitrate (PAN) in the lower atmosphere. GT-CIMS has a typical temporal resolution of 1 second and a detection limit of 10 pptv.
The Thermal-Dissociation Laser Induced Fluorescence (TD-LIF) is an in situ airborne sensor developed at UC Berkeley. It uses a combination of the TD and LIF techniques to measure nitrogen dioxide (NO2), peroxynitrates, nitric acid (HNO3), and other stable organic nitrates in the atmosphere. TD-LIF operates at the 585 nm wavelength and has a typical measurement frequency of 1 Hz.
The Proton Transfer Mass Spectrometer (PTR-MS) is an in situ airborne and ground-based spectrometer designed by the University of Innsbruck in Austria. It measures volatile organic compounds (VOCs) without sample preparation at very low concentrations. PTR-MS uses chemical ionization mass spectroscopy allowing for fast and highly sensitive detection of VOCs. It has a 0.5 to 1 s signal integration time.
Aethalometer is an in situ aerosol instrument manufactured by Magee Scientific that can be deployed on either airborne or ground-based platforms. It samples aerosols through a filter tape and measures the attenuation of transmitted light to determine the concentration of black carbon particles. The Aethalometer operates across seven optical wavelengths (370, 470, 520, 590, 660, 880, and 950 nm) and can provide data at a rate of 1 Hz. It has a measurement range of 0-500 μg per cubic meter and a resolution of 0.1 μg per cubic meter.
If instrument mode or detailed specification information is not available, can use this entry for spectrometers of various types. A spectrometer is an instrument that measures a range of a characteristic for a given substance or wavelength. There are many different types of spectrometers. Some examples are mass spectrometers, spectrophotometers, and magnetic radiation spectrometers.
A TUNABLE DIODE LASER is a solid-state laser in which as lasing is achieved by passing an injection current through the active region of a semiconductor across the p-n junction; tunable meaning it is used with a technique based upon the measurement of light absorption upon irrigating a sample using a tunable laser source.
The Airborne Tropospheric Hydrogen Oxides Sensor (ATHOS) is an in situ airborne sensor developed by Penn State University. ATHOS uses a laser-induced fluorescence (LIF) technique to measure hydroxide (OH) and hydroperoxyl (HO2) in the atmosphere. ATHOS operates near the 308 nm wavelength, has a pulse repetition frequency of 3 kHz, and has a typical time resolution of 20-30 s. It was designed to be equipped on NASA’s DC-8 aircraft and can collect measurements of OH and HO2 in clear sky and light cloud conditions.
The CalTech Chemical Ionization Mass Spectrometer (CIT-CIMS) is an in situ airborne single mass spectrometer. CIT-CIMS utilizes CF3O-ion chemistry and compact time-of-flight and triple quadrupole spectrometers to measure specific atmospheric trace gases such as nitric acid, hydrogen peroxide, and sulfur dioxide. It was designed with rapid scan capabilities, allowing it to operate at a high temporal resolution (10 Hz) and detect a wide mass range. CIT-CIMS is typically used for airborne observations, but it can be used for ground-based observations as well.
The Differential Absorption Lidar (DIAL) is an airborne lidar system designed at NASA’s Langley Research Center (LaRC). It uses four lasers to detect lidar backscatter to provide profile measurements of ozone and aerosols in the atmosphere. DIAL operates in the ultraviolet (289-300 nm) for ozone measurements and operates in the visible (572-600 nm) and infrared (1064 nm) for aerosols. It has a horizontal spatial resolution of approximately 15 km and has a measurement accuracy of 5 ppbv.
Earth Science > Spectral/engineering > Lidar > Lidar Depolarization Ratio
The Whole Air Sampler (WAS) is an airborne in-situ instrument that collects samples of air for analysis of trace gases, such as nonmethane hydrocarbons (NMHCs), Halocarbons, Alkyl Nitrates, and various sulfur compounds that are present in the troposphere. Air samples collected via the WAS then undergo gas chromatography and mass spectrometry to determine which gasses are present in the sample. The WAS collects samples every minute, which enables scientists to get a clear picture of the chemical composition of the environment as research aircraft pass through.
The Condensation Nuclei Counter (CNC) is optical method for
counting atmospheric aerosol particles.
Earth Science > >
Nephelometers are in situ airborne or ground-based optical sensors. They measure the total scattering and backscattering of aerosol particles in the atmosphere. Nephelometers operate across three wavelengths: 450 nm, 550 nm, and 700 nm, and have a typical time resolution of 1 Hz.
