<p>A long time ago I did some reading on Mie scattering and atmospheric particulate counting and I got sidetracked on raindrop characterization.</p>
<p>I remember reading about light and laser based scatterometers that measured dark pulses as water droplets passed through the beam between a light source and a detector and attenuated it, and also bright pulses seen in detectors off to the side that recorded small and large angle scattered light from the water droplets.</p>
<p>Analysis of histograms of the amplitudes of the bright and dark pulses and to some extent other parameters allowed for an analysis of droplet size frequencies along the path that an aircraft flew in real time.</p>
<p><strong>Question:</strong> What are those optical precipitation and water droplet characterization instruments called that they put on meteorological aircraft? How do they work?</p>

CC BY-SA 4.0
2021-08-01T13:43:22.323Z
usefu link https://www.nasa.gov/mission_pages/hurricanes/missions/grip/instruments/index.html
John
CC BY-SA 4.0
2021-08-01T23:06:07.593Z
@John Thanks! That lead (indirectly) to these products ([1](https://www.dropletmeasurement.com/product/cloud-droplet-probe/), [2](https://www.dropletmeasurement.com/product/cloud-aerosol-and-precipitation-spectrometer-with-depolarization/), [3](https://www.dropletmeasurement.com/product/cloud-imaging-probe/), [4](https://www.dropletmeasurement.com/product/meteorological-particle-spectrometer/)) On those pages I scrolled down and clicked the "Technology" tab. Yes this is the kind of thing I'm remembering.
uhoh
CC BY-SA 4.0
2021-11-22T13:49:14.210Z
To me the description sounds like a *disdrometer*. I know some people using them to get particle size distribution of volcanic ash (recent example at La Palma: https://twitter.com/EUROVOLC/status/1450767546374934536). But I know they were first conceived to measure water droplets.
Jean-Marie Prival
<meteorology><precipitation><remote-sensing><rain><instrumentation>
What are those precipitation and water droplet characterization instruments called that they put on meteorological aircraft? How do they work?
uhoh
# What are those precipitation and water droplet characterization instruments called that they put on meteorological aircraft? How do they work?

(Asked by: username_0 on 2021-08-01)

A long time ago I did some reading on Mie scattering and atmospheric particulate counting and I got sidetracked on raindrop characterization.

I remember reading about light and laser based scatterometers that measured dark pulses as water droplets passed through the beam between a light source and a detector and attenuated it, and also bright pulses seen in detectors off to the side that recorded small and large angle scattered light from the water droplets.

Analysis of histograms of the amplitudes of the bright and dark pulses and to some extent other parameters allowed for an analysis of droplet size frequencies along the path that an aircraft flew in real time.

**Question:** What are those optical precipitation and water droplet characterization instruments called that they put on meteorological aircraft? How do they work?

**Tags:** meteorology, precipitation, remote-sensing, rain, instrumentation

> **Comments:**
> **username_1**: usefu link https://www.nasa.gov/mission_pages/hurricanes/missions/grip/instruments/index.html  
> **username_0**: @username_1 Thanks! That lead (indirectly) to these products ([1](https://www.dropletmeasurement.com/product/cloud-droplet-probe/), [2](https://www.dropletmeasurement.com/product/cloud-aerosol-and-precipitation-spectrometer-with-depolarization/), [3](https://www.dropletmeasurement.com/product/cloud-imaging-probe/), [4](https://www.dropletmeasurement.com/product/meteorological-particle-spectrometer/)) On those pages I scrolled down and clicked the "Technology" tab. Yes this is the kind of thing I'm remembering.  
> **username_2**: To me the description sounds like a *disdrometer*. I know some people using them to get particle size distribution of volcanic ash (recent example at La Palma: https://twitter.com/EUROVOLC/status/1450767546374934536). But I know they were first conceived to measure water droplets.  

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## 0 answers

