A Doppler radar is a specialized radar that uses the Doppler effect to produce velocity data about objects at a distance. It does this by bouncing a microwave signal off a desired target and analyzing how the object's motion has altered the frequency of the returned signal. This variation gives direct and highly accurate measurements of the radial component of a target's velocity relative to the radar. The term applies to radar systems in many domains like aviation, police radar detectors, navigation, meteorology, etc.
Millimeter-wave cloud radars, also denominated cloud radars, are radar systems designed to monitor clouds with operating frequencies between 24 and 110 GHz. Accordingly, their wavelengths range from 1 mm to 1.11 cm, about ten times shorter than those used in conventional S band radars such as NEXRAD.
NEXRAD or Nexrad is a network of 159 high-resolution S-band Doppler weather radars operated by the National Weather Service (NWS), an agency of the National Oceanic and Atmospheric Administration (NOAA) within the United States Department of Commerce, the Federal Aviation Administration (FAA) within the Department of Transportation, and the U.S. Air Force within the Department of Defense. Its technical name is WSR-88D.
Weather radar, also called weather surveillance radar (WSR) and Doppler weather radar, is a type of radar used to locate precipitation, calculate its motion, and estimate its type. Modern weather radars are mostly pulse-Doppler radars, capable of detecting the motion of rain droplets in addition to the intensity of the precipitation. Both types of data can be analyzed to determine the structure of storms and their potential to cause severe weather.
The National Severe Storms Laboratory (NSSL) is a National Oceanic and Atmospheric Administration (NOAA) weather research laboratory under the Office of Oceanic and Atmospheric Research. It is one of seven NOAA Research Laboratories (RLs).
The constant altitude plan position indicator, better known as CAPPI, is a radar display which gives a horizontal cross-section of data at constant altitude. It has been developed by McGill University in Montreal by the Stormy Weather Group to circumvent some problems with the PPI:
The Center for Analysis and Prediction of Storms (CAPS) was established at the University of Oklahoma in 1989 as one of the first eleven National Science Foundation Science and Technology Centers. Located at the National Weather Center in Norman, Oklahoma, its mission is the development of techniques for the computer-based prediction of high-impact local weather, such as individual spring and winter storms, with the NEXRAD (WSR-88D) Doppler weather radar serving as a key data source.
Harold Edward Brooks is an American meteorologist whose research is concentrated on severe convective storms and tornadoes, particularly severe weather climatology, as well as weather forecasting.
David Atlas was an American meteorologist and one of the pioneers of radar meteorology. His career extended from World War II to his death: he worked for the US Air Force, then was professor at the University of Chicago and National Center for Atmospheric Research (NCAR), researcher at NASA and private consultant. Atlas owned 22 patents, published more than 260 papers, was a member of many associations, and received numerous honors in his field.
Leslie R. Lemon was an American meteorologist bridging research and forecasting with expertise in weather radar, particularly regarding severe convective storms. Lemon was, along with Charles A. Doswell III, a seminal contributor to the modern conception of the supercell which was first identified by Keith Browning, and he developed the Lemon technique to estimate updraft strength and thunderstorm organization also as a continuation of Browning's work.
Donald W. Burgess is an American meteorologist who has made important contributions to understanding of severe convective storms, particularly tornadoes, radar observations and techniques, as well as to training other meteorologists. He was a radar operator during the first organized storm chasing expeditions by the University of Oklahoma (OU) in the early 1970s and participated in both the VORTEX projects.
The Radar Operations Center (ROC) is a National Weather Service (NWS) unit that coordinates the development, maintenance, and training for the NEXRAD weather radar network. It is located at the National Weather Center (NWC) in Norman, Oklahoma and run by the National Oceanic and Atmospheric Administration (NOAA) in the Department of Commerce with partners at the Department of Defense and the Department of Transportation.
Edwin Kessler III was an American atmospheric scientist who oversaw the development of Doppler weather radar and was the first director of the National Severe Storms Laboratory (NSSL).
Frank Silvio Marzano was a professor at the Sapienza University of Rome, Italy who was named Fellow of the Institute of Electrical and Electronics Engineers (IEEE) in 2016 for contributions to microwave remote sensing in meteorology and volcanology. He was also a Fellow of the UK Royal Meteorological Society since 2012. In 2020 Dr. Marzano was inserted in the World's Top 2% Scientists database of Stanford University (USA).
Multifunction Phased Array Radar (MPAR) was an experimental Doppler radar system that utilized phased array technology. MPAR could scan at angles as high as 60 degrees in elevation, and simultaneously track meteorological phenomena, biological flyers, non-cooperative aircraft, and air traffic. From 2003 through 2016, there was one operational MPAR within the mainland United States—a repurposed AN/SPY-1A radar set loaned to NOAA by the U.S. Navy. The MPAR was decommissioned and removed in 2016.
The Joint Polarization Experiment (JPOLE) was a test for evaluating the performance of the WSR-88D in order to modify it to include dual polarization. This program was a joint project of the National Weather Service (NWS), the Federal Aviation Administration (FAA), and the US Air Force Meteorological Agency (AFWA), which took place from 2000-2004. It has resulted in the upgrading of the entire meteorological radar network in the United States by adding dual polarization to better determine the type of hydrometeor, and quantities that have fallen.
James F. "Jeff" Kimpel was an American atmospheric scientist with expertise on severe storms who was a provost of the University of Oklahoma (OU) and director of the National Severe Storms Laboratory (NSSL).
The RapidX-bandPolarimetric Radar, commonly abbreviated as RaXPol, is a mobile research radar designed and operated by the University of Oklahoma, led by Howard Bluestein. RaXPol often collaborates with adjacent mobile radar projects, such as Doppler on Wheels and SMART-R. Unlike its counterparts, RaXPol typically places emphasis on temporal resolution, and as such is capable of surveilling the entire local atmosphere in three dimensions in as little as 20 seconds, or a single level in less than 3 seconds.
Advanced Technology Demonstrator (ATD) is an experimental weather radar system using Phased Array technology seeking to enhance Phased Array capabilities with the addition of dual-polarity and pulse compression. Its predecessor, MPAR, was the first large-scale PAR experiment taken on by NOAA in 2003, and was deployed until its eventual decommission in favor of ATD in 2016.
Dušan S. Zrnić is an American engineer of Yugoslav origin, head of the Doppler Weather Radar and Remote Sensing Research Group at the National Severe Storms Laboratory (NSSL) as well as assistant professor of electrical engineering and meteorology at the University of Oklahoma in Norman, Oklahoma. His research interests include circuit design, applied mathematics, magnetohydrodynamics, radar signal processing, and systems design.
