scholarly journals Distinguishing Remobilized Ash From Erupted Volcanic Plumes Using Space-Borne Multiangle Imaging

2017 ◽  
Vol 44 (20) ◽  
pp. 10,772-10,779 ◽  
Author(s):  
Verity J. B. Flower ◽  
Ralph A. Kahn
Keyword(s):  
Volcanic Plumes ◽  
Multiangle Imaging

scholarly journals Galileo observations of volcanic plumes on Io

Icarus ◽  
2008 ◽  
Vol 197 (2) ◽  
pp. 505-518 ◽  
Author(s):  
P.E. Geissler ◽  
M.T. McMillan
Keyword(s):  
Volcanic Plumes

scholarly journals Differences in the Evolution of Pyrocumulonimbus and Volcanic Stratospheric Plumes as Observed by CATS and CALIOP Space-Based Lidars

Atmosphere ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 1035
Author(s):  
Kenneth Christian ◽  
John Yorks ◽  
Sampa Das
Keyword(s):  
Pacific Northwest ◽  
Stratospheric Aerosol ◽  
Volcanic Aerosol ◽  
Volcanic Plumes ◽  
Size And Shape ◽  
Altitude Dependence ◽  
Volcanic Events ◽  
Spatial Propagation ◽  
Depolarization Ratios

Recent fire seasons have featured volcanic-sized injections of smoke aerosols into the stratosphere where they persist for many months. Unfortunately, the aging and transport of these aerosols are not well understood. Using space-based lidar, the vertical and spatial propagation of these aerosols can be tracked and inferences can be made as to their size and shape. In this study, space-based CATS and CALIOP lidar were used to track the evolution of the stratospheric aerosol plumes resulting from the 2019–2020 Australian bushfire and 2017 Pacific Northwest pyrocumulonimbus events and were compared to two volcanic events: Calbuco (2015) and Puyehue (2011). The pyrocumulonimbus and volcanic aerosol plumes evolved distinctly, with pyrocumulonimbus plumes rising upwards of 10 km after injection to altitudes of 30 km or more, compared to small to modest altitude increases in the volcanic plumes. We also show that layer-integrated depolarization ratios in these large pyrocumulonimbus plumes have a strong altitude dependence with more irregularly shaped particles in the higher altitude plumes, unlike the volcanic events studied.

scholarly journals Global and regional evaluation of over-land spectral aerosol optical depth retrievals from SeaWiFS

2012 ◽  
Vol 5 (2) ◽  
pp. 2169-2220 ◽  
Author(s):  
A. M. Sayer ◽  
N. C. Hsu ◽  
C. Bettenhausen ◽  
M.-J. Jeong ◽  
B. N. Holben ◽  
...  
Keyword(s):  
North America ◽  
Aerosol Optical Depth ◽  
Optical Depth ◽  
Field Of View ◽  
Wide Field ◽  
Imaging Spectrometer ◽  
Wide Field Of View ◽  
Moderate Resolution ◽  
Resolution Imaging ◽  
Multiangle Imaging

Abstract. This study evaluates a new spectral aerosol optical depth (AOD) dataset derived from Sea-viewing Wide Field-of-view Sensor (SeaWiFS) measurements over land. First, the data are validated against Aerosol Robotic Network (AERONET) direct-sun AOD measurements, and found to compare well on a global basis. If only data with the highest quality flag are used, the correlation is 0.86 and 72% of matchups fall within an expected absolute uncertainty of 0.05 + 20% (for the wavelength of 550 nm). The quality is similar at other wavelengths and stable over the 13-yr (1997–2010) mission length. Performance tends to be better over vegetated, low-lying terrain with typical AOD of 0.3 or less, such as found over much of North America and Eurasia. Performance tends to be poorer for low-AOD conditions near backscattering geometries, where SeaWiFS overestimates AOD, or optically-thick cases of absorbing aerosol, where SeaWiFS tends to underestimate AOD. Second, the SeaWiFS data are compared with midvisible AOD derived from the Moderate Resolution Imaging Spectrometer (MODIS) and Multiangle Imaging Spectroradiometer (MISR). All instruments show similar spatial and seasonal distributions of AOD, although there are regional and seasonal offsets between them. At locations where AERONET data are available, these offsets are largely consistent with the known validation characteristics of each dataset. With the results of this study in mind, the SeaWiFS over-land AOD record is suitable for quantitative scientific use.

scholarly journals Uncertainty analysis of a model of wind-blown volcanic plumes

2015 ◽  
Vol 77 (10) ◽  
Author(s):  
Mark J. Woodhouse ◽  
Andrew J. Hogg ◽  
Jeremy C. Phillips ◽  
Jonathan C. Rougier
Keyword(s):  
Uncertainty Analysis ◽  
Volcanic Plumes

Multiangle Imaging Spectroradiometer: optical characterization of the calibration panels

1997 ◽  
Vol 36 (27) ◽  
pp. 7016 ◽  
Author(s):  
Brendan T. McGuckin ◽  
David A. Haner ◽  
Robert T. Menzies
Keyword(s):  
Optical Characterization ◽  
Multiangle Imaging ◽  
Multiangle Imaging Spectroradiometer

scholarly journals Detection of Volcanic Plumes by GPS: the 23 November 2013 Episode on Mt. Etna

2015 ◽  
Vol 57 ◽  
Author(s):  
Massimo Aranzulla ◽  
Flavio Cannavò ◽  
Simona Scollo
Keyword(s):  
Signal To Noise Ratio ◽  
Explosive Eruptions ◽  
Volcanic Plume ◽  
Test Case ◽  
Signal To Noise ◽  
Volcanic Plumes ◽  
Gps Network ◽  
Mt Etna ◽  
New Challenges ◽  
Aviation Operations

<p>The detection of volcanic plumes produced during explosive eruptions is important to improve our understanding on dispersal processes and reduce risks to aviation operations. The ability of Global Position-ing System (GPS) to retrieve volcanic plumes is one of the new challenges of the last years in volcanic plume detection. In this work, we analyze the Signal to Noise Ratio (SNR) data from 21 permanent stations of the GPS network of the Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Etneo, that are located on the Mt. Etna (Italy) flanks. Being one of the most explosive events since 2011, the eruption of November 23, 2013 was chosen as a test-case. Results show some variations in the SNR data that can be correlated with the presence of an ash-laden plume in the atmosphere. Benefits and limitations of the method are highlighted.</p>

Electrostatics and In Situ Sampling of Volcanic Plumes

Volcanic Ash ◽  
2016 ◽  
pp. 99-113 ◽  
Author(s):  
K.L. Aplin ◽  
A.J. Bennett ◽  
R.G. Harrison ◽  
I.M.P. Houghton
Keyword(s):  
Volcanic Plumes

A global perspective on Bromine monoxide composition in volcanic plumes derived from three years of S5-P/TROPOMI data

2021 ◽  
Author(s):  
Simon Warnach ◽  
Holger Sihler ◽  
Christian Borger ◽  
Nicole Bobrowski ◽  
Stefan Schmitt ◽  
...  
Keyword(s):  
Global Perspective ◽  
Coefficient Of Determination ◽  
Optical Absorption Spectroscopy ◽  
Polar Regions ◽  
Volcanic Gas ◽  
Volcanic Plumes ◽  
Molar Ratios ◽  
Volcanic Events ◽  
Global Coverage

&lt;p&gt;Bromine monoxide (BrO) is a halogen radical capable of influencing atmospheric chemical processes, in particular the abundance of ozone, e. g. in the troposphere of polar regions, the stratosphere as well as in volcanic plumes. Furthermore, the molar bromine to sulphur ratio in volcanic gas emissions is a proxy for the magmatic composition of a volcano and potentially an eruption forecast parameter.&lt;/p&gt;&lt;p&gt;The high spatial resolution of the S5-P/TROPOMI instrument (up to 3.5x5.5km&lt;sup&gt;2&lt;/sup&gt;) and its daily global coverage offer the potential to detect BrO even during minor eruptions and also to determine BrO/SO&lt;sub&gt;2&lt;/sub&gt; ratios during continuous passive degassing.&lt;/p&gt;&lt;p&gt;Here, we present a global overview of BrO/SO&lt;sub&gt;2&lt;/sub&gt; molar ratios in volcanic plumes derived from a systematic long-term investigation of three years of TROPOMI data.&lt;/p&gt;&lt;p&gt;We retrieved column densities of BrO and SO&lt;sub&gt;2&lt;/sub&gt; using Differential Optical Absorption Spectroscopy (DOAS) and calculated mean BrOSO&lt;sub&gt;2&lt;/sub&gt; molar ratios for each volcano. As expected, the calculated BrO/SO&lt;sub&gt;2&lt;/sub&gt; molar ratios differ strongly between different volcanoes ranging from several 10&lt;sup&gt;-5&lt;/sup&gt; up to several 10&lt;sup&gt;-4&lt;/sup&gt;. In our study of three years of S5P/TROPOMI data we successfully recorded elevated BrO column densities for more than 100 volcanic events and were able to derive meaningful (coefficient of determination, R&lt;sup&gt;2&lt;/sup&gt; exceeding 0.5) BrO/SO&lt;sub&gt;2&lt;/sub&gt; ratios for multiple volcanoes.&lt;/p&gt;

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