Next Article in Journal
Optimization of a Deep Convective Cloud Technique in Evaluating the Long-Term Radiometric Stability of MODIS Reflective Solar Bands
Previous Article in Journal
The Relationship between Urban Land Surface Material Fractions and Brightness Temperature Based on MESMA
Article Menu
Issue 6 (June) cover image

Export Article

Reply published on 12 October 2017, see Remote Sens. 2017, 9(10), 1040.

Comment of Remote Sens. 2017, 9(2), 146.

Open AccessComment
Remote Sens. 2017, 9(6), 534; doi:10.3390/rs9060534

The Difficulty of Measuring the Absorption of Scattered Sunlight by H2O and CO2 in Volcanic Plumes: A Comment on Pering et al. “A Novel and Inexpensive Method for Measuring Volcanic Plume Water Fluxes at High Temporal Resolution,” Remote Sens. 2017, 9, 146

U.S. Geological Survey Cascades Volcano Observatory, 1300 SE Cardinal Ct, Vancouver, WA 98683, USA
Academic Editor: Prasad S. Thenkabail
Received: 25 April 2017 / Revised: 25 April 2017 / Accepted: 19 May 2017 / Published: 27 May 2017
View Full-Text   |   Download PDF [1303 KB, uploaded 27 May 2017]   |  

Abstract

In their recent study, Pering et al. (2017) presented a novel method for measuring volcanic water vapor fluxes. Their method is based on imaging volcanic gas and aerosol plumes using a camera sensitive to the near-infrared (NIR) absorption of water vapor. The imaging data are empirically calibrated by comparison with in situ water measurements made within the plumes. Though the presented method may give reasonable results over short time scales, the authors fail to recognize the sensitivity of the technique to light scattering on aerosols within the plume. In fact, the signals measured by Pering et al. are not related to the absorption of NIR radiation by water vapor within the plume. Instead, the measured signals are most likely caused by a change in the effective light path of the detected radiation through the atmospheric background water vapor column. Therefore, their method is actually based on establishing an empirical relationship between in-plume scattering efficiency and plume water content. Since this relationship is sensitive to plume aerosol abundance and numerous environmental factors, the method will only yield accurate results if it is calibrated very frequently using other measurement techniques. View Full-Text
Keywords: volcanic gases; water vapor; carbon dioxide; remote sensing; plume imaging; passive degassing; infrared cameras; sulfur dioxide; UV cameras volcanic gases; water vapor; carbon dioxide; remote sensing; plume imaging; passive degassing; infrared cameras; sulfur dioxide; UV cameras
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Kern, C. The Difficulty of Measuring the Absorption of Scattered Sunlight by H2O and CO2 in Volcanic Plumes: A Comment on Pering et al. “A Novel and Inexpensive Method for Measuring Volcanic Plume Water Fluxes at High Temporal Resolution,” Remote Sens. 2017, 9, 146. Remote Sens. 2017, 9, 534.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Remote Sens. EISSN 2072-4292 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top