Preprints
https://doi.org/10.5194/amt-2021-44
https://doi.org/10.5194/amt-2021-44

  17 Mar 2021

17 Mar 2021

Review status: a revised version of this preprint was accepted for the journal AMT and is expected to appear here in due course.

A differential emissivity imaging technique for measuring hydrometeor mass and type

Dhiraj K. Singh1, Spencer Donovan1, Eric R. Pardyjak1, and Timothy J. Garrett2 Dhiraj K. Singh et al.
  • 1Department of Mechanical Engineering, University of Utah, Salt Lake City, UT, USA
  • 2Department of Atmospheric Sciences, University of Utah, Salt Lake City, UT, USA

Abstract. The Differential Emissivity Imaging Disdrometer (DEID) is a new evaporation-based optical and thermal instrument designed to measure the mass, size, density, and type of individual hydrometeors and their bulk properties. Hydrometeor spatial dimensions are measured on a heated metal plate using an infrared camera by exploiting the much higher thermal emissivity of water compared with metal. As a melted hydrometeor evaporates, its mass can be directly related to the loss of heat from the hotplate assuming energy conservation across the hydrometeor. The heat-loss required to evaporate a hydrometeor is found to be independent of environmental conditions including ambient wind velocity, moisture level, and temperature. The difference in heat loss for snow versus rain for a given mass offers a method for discriminating precipitation phase. The DEID measures hydrometeors at sampling frequencies up to 1 Hz with masses and effective diameters greater than 1 µg and 200 µm, respectively, determined by the size of the hotplate and the thermal camera specifications. Measurable snow water equivalent (SWE) precipitation rates range from 0.001 to 200 mm h−1, as validated against a standard weighing bucket. Preliminary field-experiment measurements of snow and rain from the winters of 2019 and 2020 provided continuous automated measurements of precipitation rate, snow density, and visibility. Measured hydrometeor size distributions agree well with canonical results described in the literature.

Dhiraj K. Singh et al.

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on amt-2021-44', Anonymous Referee #1, 12 Apr 2021
    • AC1: 'Reply on RC1', Eric Pardyjak, 14 Jun 2021
  • RC2: 'Comment on amt-2021-44', Aaron Kennedy, 18 May 2021
    • AC2: 'Reply on RC2', Eric Pardyjak, 14 Jun 2021

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on amt-2021-44', Anonymous Referee #1, 12 Apr 2021
    • AC1: 'Reply on RC1', Eric Pardyjak, 14 Jun 2021
  • RC2: 'Comment on amt-2021-44', Aaron Kennedy, 18 May 2021
    • AC2: 'Reply on RC2', Eric Pardyjak, 14 Jun 2021

Dhiraj K. Singh et al.

Dhiraj K. Singh et al.

Viewed

Total article views: 563 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
378 173 12 563 6 6
  • HTML: 378
  • PDF: 173
  • XML: 12
  • Total: 563
  • BibTeX: 6
  • EndNote: 6
Views and downloads (calculated since 17 Mar 2021)
Cumulative views and downloads (calculated since 17 Mar 2021)

Viewed (geographical distribution)

Total article views: 520 (including HTML, PDF, and XML) Thereof 520 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 

Cited

Latest update: 17 Oct 2021
Download
Short summary
This paper describes a new instrument for quantifying the physical characteristic of hydrometeors such as snow and rain. The device can measure the mass, size, density, and type of individual hydrometeors and their bulk properties. The instrument is called the Differential Emissivity Imaging Disdrometer or DEID and is composed of a thermal camera and hotplate. The DEID measures hydrometeors at sampling frequencies up to 1 Hz with masses and effective diameters greater than 1 μg and 200 μm.