Clouds, Aerosol, and Monsoon Processes-Philippines Experiment

The Three-View Particle Imager (3V-CPI) is an in-situ airborne spectrometer and particle imager made by SPEC, Inc. The 3V-CPI combines a Cloud Particle Imager (CPI) and a 2D-Stereo Particle Probe (2D-S). Its primary function is capturing high-resolution images used to determine the size, shape, and concentration of hydrometeors. The 3V-CPI offers a resolution of 10 μm and can detect hydrometeors up to 1280 μm.

The 2B Technologies Ozone (O3) Monitor is an in-situ dual-beam ozone monitor suitable for airborne and ground-based use. It measures O3 concentration through dual-beam ultraviolet (UV) absorption at 254 nm. The device has a detection range of 0 to 20 ppm, a resolution of 0.1 ppb, and provides measurements every 2 seconds. Its operating temperature range is 0 to 50 degrees Celsius, with an altitude range of approximately 0 to 13.5 km.

The Counterflow Virtual Impactor (CVI) is an in situ airborne instrument that samples cloud droplets. It samples cloud droplets by removing them from the surrounding air through inertial impaction. CVI is typically deployed with additional sensors to provide measurements of cloud particle concentration, cloud liquid water, and water vapor of the sample droplets. CVI can detect cloud droplets as small as 7 microns in diameter and has a typical time response of 1 second.

The Aerosol Mass Spectrometer (AMS) is an in situ spectrometer developed by Aerodyne Research. It employs quadrupole mass spectrometry to measure aerosol chemical composition and properties. It can detect particles ranging from 40 nm to 1 micron in size and has a time resolution of up to 10 Hz. It can be installed on aircraft, research vessels, mobile laboratories, or other ground-based platforms.

The Differential Aerosol Sizing and Hygroscopicity Spectrometer Probe (DASH-SP) is an in situ airborne spectrometer developed by Brechtel Manufacturing, Inc. It uses differential mobility analysis (DMA) combined with multiple humidification and sizing modules to measure aerosol optical size and hygroscopic growth factors. The probe can deliver faster measurement resolution compared to other hygroscopicity techniques. DASH-SP measures aerosol particles in the size range of 0.1–1.0 μm and operates at a wavelength of 532 nm. Its typical sampling rate is 1 Hz.

The Laser Aerosol Spectrometer (LAS) is an in situ airborne spectrometer manufactured by TSI, Inc. LAS measures particle size by analyzing how particles scatter light. It operates at a 633 nm wavelength and detects particles ranging from 0.09 to 7.5 μm. LAS can deliver complete particle size distributions at a rate of 10 Hz. It is commonly used as part of aerosol instrument suites, such as NASA’s Langley Aerosol Research Group Experiment (LARGE) and NOAA’s Aerosol Microphysical Properties (AMP).

The Particle Into Liquid Sampler (PILS) is an in situ aerosol sampler manufactured by Brechtel Manufacturing Inc. PILS can be used by both ground-based and airborne platforms to gather continuous data on ambient aerosol bulk composition. The particles collected by PILS are mixed with saturated water vapor to form droplets that are analyzed by either an ion chromatograph (IC) or a total organic carbon detector (TOC). PILS can detect aerosol particles ranging from 70 nm to 2.5 μm in size and offers a time resolution of 3 minutes for airborne measurements and 15 minutes for ground-based measurements.

The Particle Soot Absorption Photometer (PSAP) is an in situ airborne photometer manufactured by Radiance Research. It applies Beer's Law to measure the change in light transmission of aerosol particles. These measurements help determine aerosol absorption and extinction. PSAP operates across three wavelengths (467, 530, and 660 nm) and has a 1-second time resolution. It is usually deployed on aircraft, but it can also be used on ships and vehicles.

The Fast Integrated Mobility Spectrometer (FIMS) is an in situ airborne spectrometer that measures aerosol size distributions. It separates charged aerosol particles based on their electrical mobility and then uses a charge-coupled device (CCD) imaging system to determine a particle size distribution. FIMS can measure aerosol size distributions from 8 to 600 nm at a sampling rate of 1 Hz.

Generic-Atmospheric State (Gen-AtmsState) refers to non-specific instruments on a platform used for measurements of atmospheric state parameters. These are typically in situ sensors that measure temperature, pressure, humidity, and wind speed/direction. Types of atmospheric state instruments include thermometers, hygrometers, barometers, and anemometers.

Digital cameras are used to provide imagery for research applications. Cameras are used on aircraft to collect aerial imagery for mapping and surveying, environmental monitoring, cloud observations, agriculture, geological studies, and other Earth science applications. They are also used at field sites to capture visual observations to monitor changes in land cover, vegetation, clouds, air quality, glaciers, and other phenomena.

The Research Scanning Polarimeter (RSP) is an airborne, passive polarimeter developed by SpecTIR Corporation. It measures total radiance and linear polarization across nine spectral bands in the visible and infrared wavelengths (410-2250 nm). These measurements can be used to determine 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 approximately 100 meters at an altitude of 5 km.

The Scanning Mobility Particle Sizer (SMPS) is an in situ aerosol sensor that can be operated on airborne or ground-based platforms, manufactured by TSI Incorporated. SMPS uses a differential mobility analyzer (DMA) to measure the electrical mobility diameter of aerosol particles, which helps determine the size distribution. It also counts the number of aerosol particles using a condensation particle counter (CPC). It detects particles in the size range of 10-1000 nm and typically takes about 10 seconds to complete each scan.

The Cloud Particle Imager (CPI) is an airborne imager developed by SPEC Inc. CPI captures high-resolution (2.3 μm pixel size) images of cloud particles that pass through its sampling volume. It uses a charge-coupled device (CCD) camera operating at 810 nm to record images and can capture up to 74 frames per second with a refresh rate of 40 Hz. The images from CPI can be used to determine microphysical properties such as particle size and shape.

The Passive-Cavity Aerosol Spectrometer Probe (PCASP) is an in situ airborne optical spectrometer manufactured by Droplet Measurement Technologies. It detects light scattered by particles to determine aerosol size distribution and concentration within the 0.1 to 3.0 μm range. PCASP operates at a wavelength of 632 nm and typically samples at 10 Hz.

The Picarro gas concentration analyzer is an in situ airborne or ground-based sensor manufactured by Picarro, Inc. It uses Wavelength-Scanned Cavity Ring Spectroscopy (WS-CRDS) to measure trace gases such as carbon dioxide, carbon monoxide, methane, and water vapor. For carbon dioxide measurements, the laser within Picarro operates at 1603 nm wavelength, while 1651 nm wavelength is used for methane and water vapor measurements. Picarro has a typical sampling time of 2.5 seconds. Depending on the model, Picarro can also provide measurements of carbon isotopes for gas concentrations.

The Airborne Third Generation Precipitation Radar (APR-3) is an airborne Doppler dual-polarization radar. It measures Doppler velocity and radar reflectivity at three frequencies: 13.4 GHz, 35.6 GHz, and 94 GHz. These measurements are used to determine the vertical structures of clouds and precipitation characteristics. APR-3 has a horizontal resolution of 700-800 meters at an altitude of 10 km and a vertical resolution of 60 meters. It was developed by NASA's Jet Propulsion Laboratory (JPL) and replaced the APR-2.

The Advanced Microwave Precipitation Radiometer (AMPR) is an airborne passive microwave radiometer. AMPR provides calibrated brightness temperatures, which can be used to determine cloud and precipitation characteristics. It operates across four microwave channels: 10.7, 19.35, 37.1, and 85.5 GHz. These frequencies are sensitive to precipitation, making AMPR well-suited for studying rain events. It has a surface footprint size ranging from 640 m (85.5 GHz) to 2.8 km (10.7 GHz).

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, along with their optical and physical properties that contain BC. 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).

Broadband Radiometers (BBR) are modified versions of the Kipp & Zonen CM-22 pyranometers and CG-4 pyrgeometers. They have been adapted for use on 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.

The Solar Spectral Flux Radiometer (SSFR) is an airborne radiometer developed by the Ames Atmospheric Radiation Group. It measures solar spectral irradiance in the troposphere. SSFR works within the 300-2150 nm wavelength range and offers a spectral resolution of 8-12 nm. It typically collects data at 1 Hz and has a radiometric accuracy of 3%.

This data will be added in future versions.

The Aerodynamic Particle Sizer (APS) is an in situ spectrometer manufactured by TSI Instruments. APS measures aerodynamic particles in the 0.5-20 μm size range. It also measures the light-scattering intensity of the particles in the 0.37-20 μm optical size range. APS provides particle size distributions for 52 channels at a typical sampling time of 1 second. It uses a laser diode operating at 655 nm and has a size resolution of 0.02 μm at 1 μm. APS can be deployed on aircraft, ships, or ground-based platforms.

The Condensation Nuclei Counter (CNC) is optical method for counting atmospheric aerosol particles.

The Diode Laser Hygrometer (DLH) is an in situ airborne hygrometer developed by NASA’s Langley Research Center (LaRC). It uses tunable diode laser absorption to detect water vapor in the atmosphere. DLH operates in the near-infrared range at about 1.4 μm and has a measurement frequency of 100 Hz. It can deliver precise measurements of water vapor even when flying through clouds.

NOx/NOxy is an in situ chemiluminescence instrument that measures nitrogen oxides and ozone in the atmosphere. It offers a spatial resolution better than 100 meters at typical DC-8 research flight speeds. NOx/NOxy can be used on ground-based, airborne, and shipborne platforms, enabling it to support various atmospheric chemistry and air quality studies.

The Fast Cloud Droplet Probe (FCDP) is an in situ airborne cloud probe manufactured by SPEC Inc. The FCDP measures the concentration and size of cloud droplets by detecting light scattered by particles. It detects particles with diameters ranging from 1.5 to 50 microns and typically records measurements at 1 Hz.

The Airborne Vertical Atmospheric Profiling System (AVAPS) is an airborne system that uses dropsondes and Global Positioning System (GPS) receivers to gather in situ profiles of atmospheric parameters. It provides profile measurements of temperature, pressure, and humidity every 0.5 seconds, and atmospheric wind measurements every 0.25 seconds. AVAPS has a vertical resolution of approximately 10 meters and can launch dropsondes every 20 seconds. Developed by the National Center for Atmospheric Research (NCAR) for the NASA Global Hawk, it can also be deployed on other aircraft such as the DC-8 and P-3.

Nephelometers are in situ optical sensors that can be airborne or ground-based. They measure the total scattering and backscattering of aerosol particles in the atmosphere. Nephelometers operate at three wavelengths: 450 nm, 550 nm, and 700 nm, with a typical time resolution of 1 Hz.

The High Spectral Resolution Lidar 2 (HSRL-2) is an airborne lidar developed by NASA's Langley Research Center. HSRL-2 measures aerosol backscatter at 355, 532, and 1064 nm wavelengths and aerosol extinction at 355 and 532 nm wavelengths. It has a horizontal resolution of 1-2 km and a vertical resolution of 15 m, with measurements taken approximately every 0.5 seconds. It replaced the original High Spectral Resolution Lidar (HSRL).

The 2D-Stereo Particle Probe (2D-S) is an in situ airborne optical imaging device developed by SPEC Inc. It uses two diode laser beams to create stereo images of cloud particles via linear array shadowing. These images allow for the determination of cloud particle size distribution, particle number concentration, and ice or liquid water content. 2D-S has a resolution of 10 µm and can measure hydrometeors ranging from 25 to 1280 µm.

The Hawkeye Combination Cloud Particle Probe is an in situ airborne probe developed by SPEC, Inc. It was initially designed to be flown on NASA’s Global Hawk Uncrewed Aerial Vehicle (UAV). Hawkeye includes four probes: the Fast Cloud Droplet Probe (FCDP), a 10-micron channel 2D-S Probe, a 50-micron channel 2D-S Probe, and a Cloud Particle Imager (CPI). Hawkeye captures images of cloud particles and measures particle size distribution and concentration. The FCDP has a size range of 1.5 to 50 μm with a resolution of 3 μm. The 10-micron channel 2D-S probe covers a size range of 10 to 1280 μm, while the 50-micron channel 2D-S covers 50 to 6400 μm. The CPI provides a resolution of 2.3 μm, a size range from 2.3 to 2300 μm, and a frame rate up to 400 frames per second.

The Langley Aerosol Research Group Experiment (LARGE) is an in situ airborne instrument suite that measures aerosol and cloud microphysical and optical properties, such as size distribution, number concentration, and scattering and absorption coefficients. LARGE includes several instruments, such as the Ultra-High Sensitivity Aerosol Spectrometer (UHSAS), Particle-Into-Liquid Sampler (PILS), Particle Soot Absorption Photometer (PSAP), Cloud and Aerosol Spectrometer (CAS), Cloud Imaging Probe (CIP), and additional cloud and aerosol sensors. The LARGE instruments operate over the 450-700 nm wavelength range, detect particles ranging from 0.003 to 20 μm, and measure at a frequency of 1 Hz. It is primarily used for airborne measurements but can also be deployed on ground-based platforms like vehicles.

The High Volume Precipitation Spectrometer (HVPS) is an in situ airborne particle imager manufactured by SPEC Inc. It uses a 128-photodiode array to capture images of precipitation particles. These images can be used to determine the particles' shape, size, and concentration. HVPS-3 has a pixel resolution of 150 μm and a maximum field of view of 1.92 cm.