INSTRUMENTATION DEVELOPMENT

• Airborne Imaging Microwave Radiometer (AIMR)
  
• Bistatic Radar Network (BINET)
  
• Community Aerosol Inlet (CAI)
  
• Counterflow Virtual Impactor (CVI)
  
• Doppler on Wheels (DOW)
  
• High Power Water Vapor Differential Absorption Lidar (HPWV DIAL)
  
• High Resolution Doppler Lidar (HRDL)
  
• Inter-Continental Atmospheric Radiosonde Upper Air Sounding System (ICARUSS)
  
• Multiple Antenna Profiler (MAPR)
  
• Multiangle Aerosol Spectrometer Probe (MASP)
  
• Multichannel Cloud Radiometer (MCR)
  
• Ozone Differential Absorption Lidar (O3-DIAL)
  
• PC-based Integrated Radar Acquisition Card (PIRAQ)
  
• Scanning Aerosol Backscatter Lidar (SABL)
  
• Weather Avoidance Radar Data System (WARDS)

This radiometer operates from the NCAR/NSF C-130 aircraft, scanning across the flight track through the nadir point. The instrument measures surface and atmospheric radiation emissions at 37 and 90 GHz. Each frequency is separated into horizontally and vertically polarized channels. To date, the instrument has primarily been used for mapping of the polar ice cap (ice and snow change their radiative properties with age) but potential may exist for mapping ground moisture content as well. For more information, contact Jeff Keeler (ATD/RSF).

Bistatic Radar Network (BINET)

The S-Pol Bistatic Receiver System is a collaborative effort between ATD and the University of Oklahoma. The system provides real-time multiple-Doppler radar measurements of winds from a single transmitting radar. BINET consists of receiving antennas, radio data-transmission equipment, and real-time data display software that can be run on any X-based window system. BINET uses the S-Pol radar as a signal source and ships in the same containers along with the radar. Mitch Randall together with Joshua Wurman from the University of Oklahoma are leading the bistatic radar development.

Community Aerosol Inlet (CAI)

CAI was designed to more effectively sample aerosol particles for collective analysis. The 8-meter-long stainless steel structure is mounted on the outside of the C-130 fuselage, near the nose. It has a shroud to minimize effects of changes in airflow angle on the inlet. Several design features reduce the likelihood of flow separation. Cynthia Twohy (OSU) is leading the CAI development.

Counterflow Virtual Impactor (CVI)

The CVI samples cloud droplets or ice crystals and evaporates them, allowing the residual nuclei and volatile gases to be measured downstream by various methods. Project leader Cynthia Twohy (ATD/RAF) has been collaborating with Mary Laucks and Bob Charlson at the University of Washington to develop a computational fluid dynamics model of the CVI.

Doppler on Wheels (DOW)

The Doppler on Wheels project consists of two mobile X-band Doppler weather radars mounted on trucks that explore low-level and small scale phenomena. DOW operations permit the first ever mappings of tornado winds and resolution of detailed tornado structure and evolution at scales well below 100 m. The DOW Project is a collaborative effort between the School of Meteorology (SOM) and Center for the Analysis and Prediction of Storms (CAPS) at the University of Oklahoma and ATD, led by Joshua Wurman.

High Power Water Vapor Differential Absorption Lidar (HP WV DIAL)

The development of an advanced water vapor differential absorption lidar (DIAL) system has been started. This multi-platform system will provide 3-D water vapor fields from a ground-based platform. It will also be deployed on the new airborne platform HIAPER. The new system will have high accuracy and resolution and can operate from arctic to tropical environment as well as from the stratosphere down to the boundary layer. Please contact project manager Volker Wulfmeyer for more details on this effort.

High Resolution Doppler Lidar (HRDL)

This NOAA 2-micron, solid-state, coherent Doppler lidar is coupled with a high-speed platform attitude correction scanner and an advanced signal processor. HRDL was designed and built by NOAA/ETL to provide the high spatial and velocity resolution measurements needed to advance physical understanding of boundary layer processes. Installed on the NCAR mobile optical laboratory, it provides accurate real-time wind and backscatter measurements. In a joint effort of NOAA/ETL and NCAR/ATD it has been considerably improved with respect to frequency stability and average power. For the first time with maximum duty cycle, it was operated during the campaign NAURU99 on a shipborne platform. Volker Wulfmeyer and Mitch Randall collaborated with Alan Brewer of NOAA/ETL in this project.

Inter-Continental Atmospheric Radiosonde Sounding System (ICARUSS)

ICARUSS, also called Driftsonde, is a proposed new atmospheric sounding system, which uses a thin polyethylene ballon to lift a payload of 24 dropsondes or modified radiosondes to an altitude of about 53,000 to 60,000 ft where it will stay for five to six days.

Multiple Antenna Profiler (MAPR)

The NCAR/ARM MAPR, funded in large parts by DOE's Atmospheric Radiation Measurement (ARM) program, uses newly developed spaced-antenna techniques to measure vertical profiles of wind velocity through the lower troposphere. The goal of MAPR is to obtain better accuracy and much higher time resolution than conventional wind profilers, which measure winds through estimating Doppler shift in multiple beam directions. The MAPR development is led by Steve Cohn (ATD/SSSF).

Multiangle Aerosol Spectrometer Probe (MASP)

MASP has the unique ability to supply information about the optical properties of individual particles by providing simultaneous measurements of aerosol particle size, number concentration, and refractive index. MASP was used for the first time in the field in November 1994, as part of the instrument package on the NASA ER-2 high-altitude aircraft during the joint Airborne Southern Hemisphere Ozone Experiment/Measurements Assessing Effects of Stratospheric Aircraft (ASHOE/SA) campaign. MASP was developed under the leadership of Darrel Baumgardner (ATD/RAF) and Jim Dye (NCAR/MMM).

Multichannel Cloud Radiometer (MCR)

The MCR is a seven channel, scanning radiometer, originally designed and built at the NASA/Goddard Flight Space Center. In March 1997, a significant development effort was launched within ATD to modify and upgrade electronics and optics of the MCR and to bring the instrument back on line as a fully functional airborne remote sensing tool. The MCR is now available to users of the C-130 to obtain narrow bandwidth spectral radiance measurements at seven wavelengths in the visible, near-infrared, and infrared portions of the electromagnetic spectrum. Intended research applications for MCR include the remote retrieval of cloud and aerosol layer optical thicknesses and water vapor amounts, cloud phase and particle size studies, and visible and thermal mapping of surface and of cloud layer tops. The effort is led by Krista Laursen (ATD/RAF).

Ozone Differential Absorption Lidar (O3-DIAL)

The DIAL system, developed by EPA and now operated jointly by NOAA/ETL and NCAR/ATD, uses an excimer laser and Raman cells to transmit five wavelengths in the UV. Backscatter from these wavelengths is used to measure range-resolved profiles of ozone concentration and aerosol backscatter. The effort is led by Mike Hardesty (NOAA/ETL).

PC-based Integrated Radar Acquisition Card (PIRAQ)

PIRAQ allows easy, affordable, programmable Doppler radar data acquisition and data processing on a standard desk-top personal computer. The card incorporates a programmable timing generator, a digital intermediate frequency processor, and a digital signal processor. ATD uses PIRAQ on the SPol radar, for the Doppler on Wheels and Bistatic Radar Projects and to digitize and display data from the weather avoidance radars on the ATD research aircraft. Mitch Randall and Eric Loew led the development of PIRAQ.

Scanning Aerosol Backscatter Lidar (SABL)

The SABL lidar made its debut during the ACE-1 project in 1995 and is ATD's most requested instrument. This compact and reliable lidar detects backscatter from air molecules, aerosols, and hydrometeors (water and ice) and is used to measure and map distributions of relative aerosol concentrations. The instrument operates at two wavelengths 532 (green) and 1064 nm (infrared). On the C130 aircraft, it operates from zenith to nadir out to distances from 10 to 15 km with range resolutions down to 7.5 meters and along-track resolution to 4 meters. The lidar was amended for ground-based and ship-based operation in conjunction with an ISS.Craig Walther and Bruce Morley lead the SABL development.

Weather Avoidance Radar Data System (WARDS)

This system successfully processes data from the forward-looking weather-avoidance radar on the C- 130 and on the Electra and is now upgraded to synchronize with the master time signal on board each aircraft. An add-on unit receives data from WARDS and plots it on an aircraft track display in fixed-earth coordinates which greatly enhances the ability of the principal investigator (PI) to direct the flight by showing weather echoes within 50 to 100 km of the aircraft in all directions.