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Knowledge Expectations for METR 4623
Radar Meteorology

Purpose: This document describes the principal concepts, technical skills, and fundamental
understanding that all students are expected to possess upon completing METR 4623, Remote Sensing
in Meteorology. Individual instructors may deviate somewhat from the specific topics and order
listed here.

Pre-requisites: Grade of C or better in METR 3223, METR 3613, MATH 3113.

Students should have a basic understanding of the structure, physics and thermodynamics of the
atmosphere prior to starting this course.

Goal of the Course: This course develops quantitative relationships between the physical
characteristics of a target or set of targets illuminated by a radar pulse and the quantities
measured by weather radar. The capabilities and limitations of the various radar system designs are
examined to determine their impact on applications. A full treatment of Doppler principles,
including interpretation of Doppler radar data, is provided. Polarimetric and phased array radar
are introduced.

Topical Knowledge Expectations

I. Characteristics of a weather radar
• Understand the various components of a weather radar system, their function and limitation,
including different types of transmitters.
• Understand what is meant by beamwidth, sidelobes, gain, unambiguous range, unambiguous velocity,
the Doppler dilemma, and other common terms in weather radar.
• Understand the tradeoff in designing major components of a weather radar system.
• Be able to summarize the major characteristics of common weather radar systems, such as the
WSR-88D and TDWR, and their sampling strategies.
II. The radar equation
• Understand the propagation of electromagnetic radiation through the earth’s atmosphere including
the 4/3 R rule.
• Understand how to compute the height of the beam above the earth’s surface as a function of
the vertical distribution of temperature and moisture.
• Be able to identify conditions associated with anomalous propagation and be able to identify AP
in weather radar data.
• Understand the difference between the radar equation for point and distributed targets.
• Understand the impact of various radar parameters on sensitivity of the radar system.
• Understand the relationship between the radar cross-section, radar reflectivity, and particles
sizes for dielectric spheres undergoing Rayleigh scattering.
• Be aware of the character of particle size distributions for different type of hydrometeors.
• Be able to identify non-Rayleigh scattering such as hail spikes and reflectivity flares.