Airborne Antarctic Ozone Experiment

The Fourier Transformation Spectrometer (FTS) is a high-resolution airborne and ground-based spectrometer. FTS measures the solar radiance reflected from the surface, which can be used to derive measurements of carbon monoxide (CO), carbon dioxide (CO2), and methane (CH4) in the atmosphere. It has a spatial resolution of around 100m x 1000m and a measurement frequency of 1 Hz for typical research flight conditions.

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 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.

The Lyman-alpha Hygrometer measures the absorption by water vapor of vacuum-ultraviolet light at the Lyman-alpha wavelength of atomic hydrogen (121.6 nm). Air from outside the aircraft is brought to the absorption cell by a forward facing open-ended cone inlet (SCAI inlet) and exhausted through a scarf tube. The instrument ionizes the water molecules themselves as they pass through. Using a high intensity direct current discharge lamp, light at 121.6nm (called Lyman-alpha light) photodissociates water molecules producing excited OH radicals. Fluorescence is produced as the OH radical emits photons at 309nm. Making use of a phototube sensitive to this wavelength and a counter, the amount of OH can be calculated. The ambient air in the sample diminishes this signal by an amount proportional to the mixing ratio, so knowing the ambient pressure and temperature yields the mixing ratio from which the total water is determined. The instrument is periodically calibrated in flight by injecting a known amount of water vapor directly into the sample.

If instrument model information is not available, can use this instrument entry for temperature, pressues, wind speed, wind direction, humidity

NOx/NOxy is an in situ chemiluminescence instrument. It provides measurements of nitrogen oxides and ozone in the atmosphere at a spatial resolution better than 100m for typical DC-8 research flight speeds. NOx/NOxy can be utilized on ground-based, airborne, and shipborne platforms allowing it to be used in various types of atmospheric chemistry and air quality studies.

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 Microwave Temperature Profiler (MTP) is an airborne microwave radiometer developed by the Jet Propulsion Laboratory and later modified by NCAR. It measures thermal emissions from oxygen molecules in the atmosphere to prove temperature profiles above, below, and at flight level. It operates between 55 to 59 GHz and provides profiles every 17 seconds with 4 km horizontal spacing. MTP has a vertical resolution of 150 m near the aircraft.

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 model information is not available, can use this instrument entry for temperature, pressues, wind speed, wind direction, humidity

This data will be added in future versions

The Lyman-alpha Hygrometer measures the absorption by water vapor of vacuum-ultraviolet light at the Lyman-alpha wavelength of atomic hydrogen (121.6 nm). Air from outside the aircraft is brought to the absorption cell by a forward facing open-ended cone inlet (SCAI inlet) and exhausted through a scarf tube. The instrument ionizes the water molecules themselves as they pass through. Using a high intensity direct current discharge lamp, light at 121.6nm (called Lyman-alpha light) photodissociates water molecules producing excited OH radicals. Fluorescence is produced as the OH radical emits photons at 309nm. Making use of a phototube sensitive to this wavelength and a counter, the amount of OH can be calculated. The ambient air in the sample diminishes this signal by an amount proportional to the mixing ratio, so knowing the ambient pressure and temperature yields the mixing ratio from which the total water is determined. The instrument is periodically calibrated in flight by injecting a known amount of water vapor directly into the sample.

This data will be added in future versions.

This data will be added in future versions

This data will be added in future versions.

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.

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 the 254 nm wavelength allowing it to calculate the ozone number density due to the accurate ozone absorption cross section at that wavelength. It has a sampling rate of 2 Hz and a horizontal resolution of 100 to 200 meters at typical research flight speeds.

The NOAA Frost Point Hygrometer (FPH) is a balloon-borne sensor that collects profile measurements of atmospheric water vapor. It uses the chilled-mirror principle to measure the frost or dew point temperature up to 28 km in the atmosphere. FPH takes measurements at a vertical resolution of 5-10 m and a temporal resolution of 1-2 seconds.

NOx/NOxy is an in situ chemiluminescence instrument. It provides measurements of nitrogen oxides and ozone in the atmosphere at a spatial resolution better than 100m for typical DC-8 research flight speeds. NOx/NOxy can be utilized on ground-based, airborne, and shipborne platforms allowing it to be used in various types of atmospheric chemistry and air quality studies.

The Meteorological Measurement System (MMS) is an in situ airborne instrument used for measuring atmospheric state parameters. MMS provides high-resolution and accurate measurements of atmospheric pressure, temperature, and wind direction/speed immediately around the plane. Additional parameters can be derived such as potential temperature, true airspeed, turbulence dissipation rate, and Reynolds number. Measurements of all parameters are typically collected at a rate of 20 Hz.