The Aura Validation Experiment (AVE) was a NASA field investigation aimed at collecting measurements to validate Aura satellite observations. Based in Houston, Texas, AVE involved two deployments during the fall of 2004 and the summer of 2005. NASA’s WB-57 aircraft, equipped with various in situ and remote sensors, measured atmospheric trace gases and aerosols. AVE was funded by NASA’s Radiation Sciences and Atmospheric Composition programs.
AVE-Houston, AVE-Houston 2, AVE-WIIF
2004-10-22 — 2005-07-07
Houston, Texas, Southern United States, Gulf of Mexico
Generic-Atmospheric State (Gen-AtmsState) refers to non-specific instruments on a platform that measure atmospheric state parameters. These are typically in situ sensors that measure temperature, pressure, humidity, and wind speed and direction. Types of atmospheric state instruments include thermometers, hygrometers, barometers, and anemometers.
Earth Science > Atmosphere > Atmospheric Water Vapor
Earth Science > Atmosphere > Atmospheric Pressure
Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Indicators > Humidity
Earth Science > Atmosphere > Atmospheric Temperature > Surface Temperature > Air Temperature
Argus is a two-channel, tunable diode laser instrument developed at NASA Ames Research Center. It collects in situ measurements of atmospheric carbon monoxide (CO), nitrous oxide (N2O), and methane (CH4) using second harmonic spectroscopy. Argus operates in the mid-infrared range (3.3 and 4.7 micrometers) and has an accuracy of about 3% at data rates of 0.1 to 0.5 Hz. Its lightweight, compact design makes it ideal for small-payload platforms such as balloons and uncrewed aerial vehicles (UAVs).
The NOAA CH4 is an in situ airborne near-infrared tunable diode laser (TDL) absorption spectrometer. The laser is tuned to the methane (CH4) absorption line at 1.653 μm and measures the intensity of transmitted radiation. The CH4 concentration is then determined using the Beer-Lambert law. NOAA CH4 scans continuously across the CH4 absorption at a rate of 0.25 to 0.5 kHz and has a typical integration time of 2 seconds.
The NOAA Chemical Ionization Mass Spectrometer (NOAA-CIMS) is an in situ airborne spectrometer developed by NOAA. It was designed to provide high-precision measurements of reactive nitrogen and halogen species, including nitric acid, nitric oxide, and bromine chloride, in the upper atmosphere. It can also measure ozone and water vapor concentrations. NOAA-CIMS has a detection limit of 30 pptv and a temporal resolution of 1 second.
Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Indicators > Water Vapor
The JPL Laser Hygrometer (JLH) is an in situ airborne hygrometer developed at the Jet Propulsion Laboratory (JPL). It uses a tunable diode laser operating at 1.37 μm to measure atmospheric water vapor in the upper troposphere and lower stratosphere. JLH has a minimum spatial resolution of 25 meters and a detection range of 1 to 500 ppmv. It typically samples at 1 Hz and provides measurements with a precision of 0.05 ppmv.
Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Indicators > Water Vapor
Earth Science > Atmosphere > Atmospheric Water Vapor
The Charged-couple device (CCD) Actinic Flux Spectroradiometer (CAFS) is an in situ airborne spectroradiometer developed by the Atmospheric Radiation Investigations and Measurements (ARIM) laboratory at NCAR. CAFS measures spectrally resolved ultraviolet and visible actinic flux from 280 to 650 nm. These measurements can be used to derive photolysis frequencies for several chemical compounds, including ozone, nitrogen dioxide, formaldehyde, and nitrate. CAFS has a temporal resolution of 1 Hz and a wavelength resolution of about 1.8 nm at 297 nm.
The NOAA Pressure and Temperature (NOAA PT) is an in situ airborne probe that measures atmospheric pressure and temperature. It comprises a digital pressure-temperature transducer and slow- and fast-responding temperature probes. NOAA PT provides measurements of static and ram pressure and upper-air temperature every second. It has an accuracy of 0.5 degrees for temperature and 0.5 mbar for pressure.
Earth Science > Atmosphere > Atmospheric Pressure
Earth Science > Atmosphere > Atmospheric Temperature
Earth Science > Atmosphere > Atmospheric Temperature > Upper Air Temperature
The Cloud Physics Lidar (CPL) is an airborne lidar system designed to provide multi-wavelength measurements of cirrus and sub-visual cirrus clouds, as well as aerosols. It measures lidar backscatter at three wavelengths: 355 nm, 532 nm, and 1064 nm. These measurements can be used to determine cloud optical depth, particle size distribution, extinction profiles, aerosol layers, and other properties. CPL has a vertical resolution of 30 m and a typical horizontal resolution of 200 m. It has a measurement sampling rate of 1 Hz.
The NOAA Dual-Beam UV-Absorption Ozone Photometer (NOAA-O3) is an in situ optical balloon-borne and airborne instrument that measures ozone concentrations in the troposphere and lower stratosphere. It operates at 254 nm, enabling calculation of ozone number density from the precise ozone absorption cross section at that wavelength. It has a sampling rate of 2 Hz and a horizontal resolution of 100 to 200 meters during typical research flights.
Earth Science > Atmosphere > Air Quality > Tropospheric Ozone
The Single Particle Soot Photometer (SP2) is an in situ laser-induced photometer developed by Droplet Measurement Technologies. SP2 measures the black carbon (BC) mass in individual aerosol particles and their optical and physical properties. The device detects aerosol particles with diameters of 200-400 nm and can analyze up to 25,000 particles per second. It operates at a sampling rate of 1 Hz and uses a wavelength of 1.06 μm. It can be used on airborne or ground-based platforms and paired with a Humidified-Dual SP2 (HD-SP2).
The Scanning High-resolution Interferometer Sounder (S-HIS) is an airborne cross-track scanning interferometer developed by the Space Science and Engineering Center at the University of Wisconsin-Madison. It measures emitted thermal radiation between 3.3 and 18 microns with high spectral resolution. These measurements are used to derive atmospheric profiles of temperature and water vapor under clear-sky conditions. S-HIS has a spatial resolution of 2 km and a swath width of 40 km at an altitude of 20 km at nadir. It operates at a sampling frequency of 0.5 seconds and has an absolute radiance accuracy of 0.2 K.
Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Profiles
Earth Science > Atmosphere > Atmospheric Temperature
Earth Science > Atmosphere > Atmospheric Water Vapor
The NOAA Frost Point Hygrometer (FPH) is a balloon-borne sensor that collects profiles of atmospheric water vapor. It uses the chilled-mirror principle to determine the frost or dew point temperature up to 28 km in the atmosphere. FPH measures with a vertical resolution of 5-10 m and a temporal resolution of 1-2 seconds.
Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Profiles
Earth Science > Atmosphere > Atmospheric Water Vapor
Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Indicators > Dew Point Temperature
Ozonesondes are in situ balloon-borne instruments that measure ozone concentration profiles. An ozonesonde consists of an electrochemical ozone sensor connected to a meteorological radiosonde, which collects ozone, temperature, pressure, and humidity measurements as it ascends through the atmosphere. It provides ozone profile measurements at a resolution of 100 to 150 m. Ozonesondes typically operate at a measurement rate of 0.1 Hz and can collect profiles up to around 35 km.
Earth Science > Atmosphere > Atmospheric Water Vapor
Earth Science > Atmosphere > Atmospheric Pressure
Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Profiles
Earth Science > Atmosphere > Atmospheric Temperature > Upper Air Temperature > Vertical Profiles
The NOAA Pressure and Temperature (NOAA PT) is an in situ airborne probe that measures atmospheric pressure and temperature. It comprises a digital pressure-temperature transducer and slow- and fast-responding temperature probes. NOAA PT provides measurements of static and ram pressure and upper-air temperature every second. It has an accuracy of 0.5 degrees for temperature and 0.5 mbar for pressure.
Earth Science > Atmosphere > Atmospheric Pressure
Earth Science > Atmosphere > Atmospheric Temperature
Earth Science > Atmosphere > Atmospheric Temperature > Upper Air Temperature
The Harvard Hydroxyl Experiment (HOx) is an in situ laser-induced fluorescence (LIF) sensor developed by Harvard University. It uses LIF at 309 nm to measure the hydroxyl radical (OH). The OH is then excited to its first electronic state using a tunable ultraviolet laser near 282 nm. The hydroperoxyl radical (HO2) is measured as OH after chemical titration with nitric oxide. HOx has a short integration time of less than 20 seconds.
The High-Sensitivity Fast-Response CO2 Analyzer (Harvard CO2) is an in situ airborne spectrometer operated by Harvard University. It measures carbon dioxide (CO2) concentrations using a modified nondispersive infrared analyzer. CO2 mixing ratios are determined by measuring absorption at 4.26 μm. Harvard CO2 has a sampling rate of 0.5 Hz and a precision of 0.05 ppm. Harvard CO2 is typically deployed on high-altitude aircraft such as the ER-2, but it has also been used for balloon-borne measurements.
The Integrated Cavity Output Spectrometer (ICOS) is an airborne in situ spectrometer developed by Harvard University. It is a mid-infrared (6.7 μm) spectrometer that measures the primary isotopologues of water vapor in the upper troposphere and lower stratosphere. It has been integrated onto NASA’s WB-57 aircraft for field investigations of water vapor. It has an average data acquisition rate of 1 Hz and a measurement precision of 0.14 ppbv for water vapor in 4-second averages.
Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Indicators > Water Vapor
Earth Science > Atmosphere > Atmospheric Water Vapor
The PAN and Trace Hydrohalocarbon ExpeRiment (PANTHER) is an in situ airborne analyzer that uses electron capture detection and gas chromatography to measure trace gases, including methane, peroxyacyl nitrate (PAN), and carbon monoxide. PANTHER has a sampling frequency of 60 to 120 seconds and an accuracy of about 2% for most species, except PAN, which is 10%. The development of PANTHER was funded by NASA’s Instrument Incubator Program and NOAA’s Climate and Global Change Program.
The NOAA Dual-Beam UV-Absorption Ozone Photometer (NOAA-O3) is an in situ optical balloon-borne and airborne instrument that measures ozone concentrations in the troposphere and lower stratosphere. It operates at 254 nm, enabling calculation of ozone number density from the precise ozone absorption cross section at that wavelength. It has a sampling rate of 2 Hz and a horizontal resolution of 100 to 200 meters during typical research flights.
Earth Science > Atmosphere > Air Quality > Tropospheric Ozone
The Airborne Compact Atmospheric Mapper (ACAM) is a remote-sensing airborne spectrometer developed at NASA's Goddard Space Flight Center (GSFC). It uses two thermally stabilized spectrometers to measure nitrogen dioxide, sulfur dioxide, ozone, formaldehyde, and aerosols across the ultraviolet, visible, and near-infrared spectra (310-900 nm). ACAM typically operates at a spatial resolution of 30 meters and a temporal resolution of 2 Hz. ACAM data can be used for calibration and validation of observations from the Aura satellite.
The Nucleation-mode Aerosol Size Spectrometer (NMASS) is an airborne, in situ spectrometer that measures particle size distribution and cloud condensation nuclei (CCN). NMASS includes five parallel condensation nucleus counters (CNCs) that sample particles from 3 to 60 nm in diameter. It can be mounted on various aircraft and is ideal for sampling cirrus clouds in the upper atmosphere. NMASS provides rapid measurements with a temporal resolution of 10 Hz.
Harvard Water Vapor (HWV) is an in situ airborne hygrometer developed at Harvard University that measures water vapor mixing ratios in the upper troposphere and lower stratosphere. HWV includes two instruments that use different methods to detect water vapor: the Lyman-α photo-fragment fluorescence instrument (LyA) and a tunable diode laser direct absorption instrument (HHH - Harvard Herriott Hygrometer). By combining both instruments, HWV can identify and reduce systematic errors during flight. It provides measurements of water vapor mixing ratio from 1 to 1000 ppmv at 1 Hz, with an accuracy of 5%.
Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Indicators > Water Vapor
Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Profiles > Water Vapor Mixing Ratio Profiles
Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Indicators
Earth Science > Atmosphere > Atmospheric Water Vapor
The JPL Laser Hygrometer (JLH) is an in situ airborne hygrometer developed at the Jet Propulsion Laboratory (JPL). It uses a tunable diode laser operating at 1.37 μm to measure atmospheric water vapor in the upper troposphere and lower stratosphere. JLH has a minimum spatial resolution of 25 meters and a detection range of 1 to 500 ppmv. It typically samples at 1 Hz and provides measurements with a precision of 0.05 ppmv.
Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Indicators > Water Vapor
Earth Science > Atmosphere > Atmospheric Water Vapor
The Cloud Spectrometer and Impactor (CSI) is an in situ airborne probe that measures total condensed water (TCW) content in clouds. It combines a counterflow virtual impactor (CVI) with a lightweight cloud droplet probe. It measures cloud particles from 2 to 50 μm and has a typical sampling frequency of 1 second.
The Scanning High-resolution Interferometer Sounder (S-HIS) is an airborne cross-track scanning interferometer developed by the Space Science and Engineering Center at the University of Wisconsin-Madison. It measures emitted thermal radiation between 3.3 and 18 microns with high spectral resolution. These measurements are used to derive atmospheric profiles of temperature and water vapor under clear-sky conditions. S-HIS has a spatial resolution of 2 km and a swath width of 40 km at an altitude of 20 km at nadir. It operates at a sampling frequency of 0.5 seconds and has an absolute radiance accuracy of 0.2 K.
Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Profiles
Earth Science > Atmosphere > Atmospheric Temperature
Earth Science > Atmosphere > Atmospheric Water Vapor
The Meteorological Measurement System (MMS) is an in situ airborne instrument that measures atmospheric state parameters. MMS provides high-resolution, accurate measurements of atmospheric pressure, temperature, and wind direction and speed immediately around the aircraft. Additional parameters that can be derived include potential temperature, true airspeed, turbulence dissipation rate, and Reynolds number. Measurements of all parameters are typically collected at a rate of 20 Hz.
The Whole Air Sampler (WAS) is an airborne in situ instrument that collects air samples for analyzing trace gases, including nonmethane hydrocarbons (NMHCs), halocarbons, alkyl nitrates, and various sulfur compounds in the troposphere. Air samples collected by the WAS are then analyzed using gas chromatography and mass spectrometry to identify the gases present. The WAS collects samples every minute, allowing scientists to obtain a clear picture of the environment's chemical composition as research aircraft pass through.
The Microwave Temperature Profiler (MTP) is an airborne microwave radiometer developed by the Jet Propulsion Laboratory and later modified by NCAR. It measures brightness temperature from oxygen molecules at 56.363 GHz, 57.612 GHz, and 58.363 GHz. These measurements are converted to air temperature through a statistical retrieval process. It samples across 10 viewing angles and has a vertical resolution of 150 m near the aircraft. MTP provides profiles every 17 seconds, with about 4 km of horizontal spacing.
Earth Science > Spectral/engineering > Microwave > Brightness Temperature
The Cloud Physics Lidar (CPL) is an airborne lidar system designed to provide multi-wavelength measurements of cirrus and sub-visual cirrus clouds, as well as aerosols. It measures lidar backscatter at three wavelengths: 355 nm, 532 nm, and 1064 nm. These measurements can be used to determine cloud optical depth, particle size distribution, extinction profiles, aerosol layers, and other properties. CPL has a vertical resolution of 30 m and a typical horizontal resolution of 200 m. It has a measurement sampling rate of 1 Hz.
The Charged-couple device (CCD) Actinic Flux Spectroradiometer (CAFS) is an in situ airborne spectroradiometer developed by the Atmospheric Radiation Investigations and Measurements (ARIM) laboratory at NCAR. CAFS measures spectrally resolved ultraviolet and visible actinic flux from 280 to 650 nm. These measurements can be used to derive photolysis frequencies for several chemical compounds, including ozone, nitrogen dioxide, formaldehyde, and nitrate. CAFS has a temporal resolution of 1 Hz and a wavelength resolution of about 1.8 nm at 297 nm.
The Focused Cavity Aerosol Spectrometer (FCAS) is an in situ airborne optical particle counter developed by Particle Measuring Systems, Inc. FCAS detects light scattered by individual aerosol particles to determine their size distribution. It detects aerosol particles from 0.06 to 2 μm and operates at altitudes up to 20 km. Typically, FCAS provides measurements every 10 seconds.
The Airborne Laser Infrared Absorption Spectrometer (ALIAS) is an in situ airborne spectrometer developed by the Jet Propulsion Laboratory. It can also be deployed on balloons. It uses mid-infrared (3.4–8 μm) absorption spectroscopy to measure atmospheric gases, including nitrous oxide (N2O), nitrogen dioxide (NO2), nitric acid (HNO3), hydrochloric acid (HCl), carbon monoxide (CO), and methane (CH4). ALIAS has a vertical resolution of 15 m and a time resolution of 3 seconds or less.
Argus is a two-channel, tunable diode laser instrument developed at NASA Ames Research Center. It collects in situ measurements of atmospheric carbon monoxide (CO), nitrous oxide (N2O), and methane (CH4) using second harmonic spectroscopy. Argus operates in the mid-infrared range (3.3 and 4.7 micrometers) and has an accuracy of about 3% at data rates of 0.1 to 0.5 Hz. Its lightweight, compact design makes it ideal for small-payload platforms such as balloons and uncrewed aerial vehicles (UAVs).
