American Meteorological Society Certification Remote Sensing and Atmospheric Observation 1 — Questions and Answers
Question 1: What does radar reflectivity (dBZ) measure in meteorological applications?
- Wind speed and direction
- Intensity of precipitation by measuring returned energy from hydrometeors (Correct answer)
- Cloud top temperature
- Atmospheric pressure
Correct answer: Intensity of precipitation by measuring returned energy from hydrometeors
Radar reflectivity (dBZ) measures the intensity of returned microwave energy from precipitation particles, indicating rainfall or snowfall rates.
Question 2: What does Doppler radar velocity data measure that standard reflectivity cannot?
- Precipitation type
- Radial wind velocity (toward or away from the radar) (Correct answer)
- Cloud thickness
- Lightning frequency
Correct answer: Radial wind velocity (toward or away from the radar)
Doppler radar measures the phase shift of returned radar pulses to determine the radial velocity of precipitation moving toward or away from the radar.
Question 3: What is the purpose of dual-polarization radar technology?
- Increase radar range
- Distinguish precipitation types (rain, snow, hail, graupel) and improve QPE (Correct answer)
- Reduce ground clutter
- Measure upper-level winds
Correct answer: Distinguish precipitation types (rain, snow, hail, graupel) and improve QPE
Dual-polarization radar transmits both horizontal and vertical pulses, allowing discrimination of hydrometeor types and improving quantitative precipitation estimates.
Question 4: Geostationary satellites like GOES remain fixed over one location because they orbit at what altitude?
- 800 km
- 35,786 km (geosynchronous orbit) (Correct answer)
- 1,000 km
- 22,000 km
Correct answer: 35,786 km (geosynchronous orbit)
Geostationary satellites orbit at ~35,786 km where orbital period equals Earth's rotation, keeping them stationary relative to the surface.
Question 5: Infrared (IR) satellite imagery detects what property to infer cloud heights?
- Cloud albedo (reflectivity)
- Cloud top temperature (colder = higher) (Correct answer)
- Cloud thickness
- Cloud water content
Correct answer: Cloud top temperature (colder = higher)
IR satellite detects emitted thermal radiation; since temperature decreases with altitude, colder cloud tops appear brighter and indicate higher clouds.
Question 6: Water vapor satellite imagery detects radiation in what spectral band?
- Visible light (~0.5 μm)
- Water vapor absorption band (~6.2–7.3 μm) (Correct answer)
- Near-infrared (~1.6 μm)
- Thermal window (~10.7 μm)
Correct answer: Water vapor absorption band (~6.2–7.3 μm)
Water vapor imagery uses the 6.2–7.3 μm absorption band where water vapor absorbs and re-emits radiation, revealing moisture in the mid-to-upper troposphere.
American Meteorological Society Certification Remote Sensing and Atmospheric Observation 1
What does radar reflectivity (dBZ) measure in meteorological applications?