The CAMEX-3 Jet Propulsion Laboratory (JPL) Laser Hygrometer datasets consists of timeline measurements of water vapor content colllected during DC-8 flights flown during August and September of 1998. The JPL Laser Hygrometer acquired in situ measurments of the free airstream beyond the boundary layer within the immediate proximity of the aircraft along the flight track.

This CAMEX-3 Jet Propulsion Laboratory (JPL) Surface Acoustic Wave (SAW) Hygrometer dataset consists of dewpoint timeline measurements acquired during each DC-8 flight in August and September of 1998.

The CAMEX-4 JPL Laser Hygrometer dataset contains water vapor volume and mixing ratio concentractions collected during the CAMEX-4 campaign to study tropical cyclones. The Laser Hygrometer measures in situ water vapor content using a tuneable laser emitting at 1.37 microns. Absorption at that wavelength is a function of water vapor content, thus measuring the amount of absorption in an open path beyond the aircraft boundary layer, a value of water vapor pressure is made. The maximum sampling rate is 8 Hz, but the instrument is normally configured through the software for a 1Hz sampling rate.

This CAMEX-3 Jet Propulsion Laboratory (JPL) Surface Acoustic Wave (SAW) Hygrometer dataset consists of dewpoint timeline measurements acquired during each DC-8 flight in August and September of 1998.

The CAMEX-4 JPL Laser Hygrometer dataset contains water vapor volume and mixing ratio concentractions collected during the CAMEX-4 campaign to study tropical cyclones. The Laser Hygrometer measures in situ water vapor content using a tuneable laser emitting at 1.37 microns. Absorption at that wavelength is a function of water vapor content, thus measuring the amount of absorption in an open path beyond the aircraft boundary layer, a value of water vapor pressure is made. The maximum sampling rate is 8 Hz, but the instrument is normally configured through the software for a 1Hz sampling rate.

MACPEX_Water_AircraftInSitu_WB57_Data is the in-situ water data collection during the Mid-latitude Airborne Cirrus Properties Experiment (MACPEX). Data was collected by the Harvard Water Vapor (HWV), Closed-path Laser Hygrometer (CLH), Diode Laser Hygrometer (DLH), JPL Laser Hygrometer (JLH), Unmanned Aerial System Laser Hygrometer (ULH), Fast In-situ Stratospheric Hygrometer (FISH), NOAA Chemical Ionization Mass Spectrometer (CIMS), and the Aircraft Laser Infrared Absorption Spectrometer (ALIAS). Data collection for this product is complete. The MACPEX mission was an airborne field campaign that deployed from March 18th to April 26th, 2011. MACPEX sought to investigate cirrus cloud properties and the processes that affect their impact on radiation. The campaign conducted science flights using the NASA WB-57 aircraft based out of Ellington Airfield, Texas. Science flights were focused on the central North America vicinity, with an emphasis over the Southern Great Plains atmospheric observatory (established by the Department of Energy’s (DoE) Atmospheric Radiation Measurement (ARM) user facility) site in Oklahoma. MACPEX was a joint effort between NASA, the NOAA Earth System Research Laboratory (ESRL), the National Center for Atmospheric Research (NCAR), and several U.S. universities. The WB-57 contained a comprehensive instrument payload for detailed in-situ measurements that were targeted to answer MACPEX’s four major science questions. The first science question that MACPEX explored was how prevalent the smaller crystals are in cirrus clouds, and how important they are for extinction, radiative forcing, and radiative heating. MACPEX also sought to understand how cirrus microphysical properties (particle size distribution, ice crystal habit, extinction, ice water content) are related to the dynamical forcing driving cloud formation. Researchers also investigated how cirrus microphysical properties are related to aerosol loading and composition, including the abundance of heterogeneous ice nuclei. Lastly, this campaign examined how cirrus microphysical properties evolve through the lifecycles of the clouds, and the role radiatively driven dynamical motions play. In addition to the in-situ measurements, four flights were coordinated to validate the NASA EOS/A-Train satellite observations. NOAA also launched balloon sondes and ozonesondes, which were used to acquire data about the frost point and water vapor in the atmosphere. The balloon sondes and ozonesondes also acquired pressure, temperature, and humidity data, as well as measurements regarding the ozone in the atmosphere.

The NAMMA Diode Laser Hygrometer (DLH) dataset uses the DLH, a near-infrared spectrometer operating from aircraft platforms, was developed by NASA's Langley and Ames Research Centers. It measures water vapor mixing ratio and derives water vapor partial pressure, relative humidity, and water vapor flux. Based upon near-infrared tunable diode technology, its spectrometer provides true in situ monitoring of water vapor concentrations with precision levels exceeding those of existing Lyman alpha and frost point hygrometers. These data files were generated during support of the NASA African Monsoon Multidisciplinary Analyses (NAMMA) campaign, a field research investigation sponsored by the Science Mission Directorate of the National Aeronautics and Space Administration (NASA). This mission was based in the Cape Verde Islands, 350 miles off the coast of Senegal in west Africa. Commencing in August 2006, NASA scientists employed surface observation networks and aircraft to characterize the evolution and structure of African Easterly Waves (AEWs) and Mesoscale Convective Systems over continental western Africa, and their associated impacts on regional water and energy budgets.

The CAMEX-4 NOAA Lyman-Alpha Hygrometer dataset was collected by the NOAA Lyman-alpha Total Water Hygrometer, which was flown during the fourth field campaign in the CAMEX series (CAMEX-4). CAMEX-4 ran from 16 August to 24 September 2001 and was based out of Jacksonville Naval Air Station, Florida, and included missions in the Gulf of Mexico, Caribbean and Western Atlantic. The experiment focused on the study of tropical cyclone (hurricane) development, tracking, intensification, and landfalling impacts using both NASA-funded aircraft and surface remote sensing instrumentation.

The CAMEX-4 LIDAR Atmospheric Sensing Experiment (LASE) dataset was collected by the LASE instrument, which is an airborne DIAL (Differential Absorption Lidar) system used to measure water vapor, aerosols, and clouds throughout the troposphere. LASE operates by locking to a strong water vapor line and electronically tuning to any spectral position on the absorption line to choose the suitable absorption cross-section for optimum measurements over a range of water vapor concentrations in the atmosphere. During CAMEX-4, LASE operated from the NASA DC-8 using strong and weak water vapor lines in both the nadir and zenith modes, thereby simultaneously acquiring data below and above the aircraft.

The CAMEX-4 LIDAR Atmospheric Sensing Experiment (LASE) dataset was collected by the LASE instrument, which is an airborne DIAL (Differential Absorption Lidar) system used to measure water vapor, aerosols, and clouds throughout the troposphere. LASE operates by locking to a strong water vapor line and electronically tuning to any spectral position on the absorption line to choose the suitable absorption cross-section for optimum measurements over a range of water vapor concentrations in the atmosphere. During CAMEX-4, LASE operated from the NASA DC-8 using strong and weak water vapor lines in both the nadir and zenith modes, thereby simultaneously acquiring data below and above the aircraft.