In a companion paper (Horváth et al., 2021), we introduced a new technique to estimate volcanic eruption column height from extremely oblique near-limb geostationary views. The current paper demonstrates and validates the technique in a number of recent eruptions, ranging from ones with weak columnar plumes to subplinian events with massive umbrella clouds and overshooting tops that penetrate the stratosphere. Due to its purely geometric nature, the new method is shown to be unaffected by the limitations of the traditional brightness temperature method, such as height underestimation in subpixel and semitransparent plumes, ambiguous solutions near the tropopause temperature inversion, or the lack of solutions in undercooled plumes. The side view height estimates were in good agreement with plume heights derived from ground-based video and satellite stereo observations, suggesting they can be a useful complement to established techniques

Bril, A. A.

Buehler, S. A.

Carr, J. L.

Girina, O. A.

Horváth, A.

Hoshyaripour, G. A.

Mazurov, A. A.

Melnikov, D. V.

Wu, D. L.

Atmospheric Chemistry and Physics

English

A geometric technique is introduced to estimate the
height of volcanic eruption columns using the generally discarded near-limb
portion of geostationary imagery. Such oblique observations facilitate a
height-by-angle estimation method by offering close-to-orthogonal side views of eruption columns protruding from the Earth ellipsoid. Coverage is
restricted to daytime point estimates in the immediate vicinity of the vent, which nevertheless can provide complementary constraints on source
conditions for the modeling of near-field plume evolution. The technique is best suited to strong eruption columns with minimal tilting in the radial
direction. For weak eruptions with severely bent plumes or eruptions with
expanded umbrella clouds the radial tilt/expansion has to be corrected for
either visually or using ancillary wind profiles. Validation on a large set
of mountain peaks indicates a typical height uncertainty of ±500 m
for near-vertical eruption columns, which compares favorably with the
accuracy of the common temperature method.</p

Á. Horváth

J. L. Carr

O. A. Girina

D. L. Wu

A. A. Bril

A. A. Mazurov

D. V. Melnikov

G. A. Hoshyaripour

S. A. Buehler

Directory of Open Access Journals

Geometric estimation of volcanic eruption column height from GOES-R near-limb imagery – Part 1: Methodology

A geometric technique is introduced to estimate the height of volcanic eruption columns using the generally discarded near-limb portion of geostationary imagery. Such oblique observations facilitate a height-by-angle estimation method by offering close-to-orthogonal side views of eruption columns protruding from the Earth ellipsoid. Coverage is restricted to daytime point estimates in the immediate vicinity of the vent, which nevertheless can provide complementary constraints on source conditions for the modeling of near-field plume evolution. The technique is best suited to strong eruption columns with minimal tilting in the radial direction. For weak eruptions with severely bent plumes or eruptions with expanded umbrella clouds the radial tilt/expansion has to be corrected for either visually or using ancillary wind profiles. Validation on a large set of mountain peaks indicates a typical height uncertainty of ±500 m for near-vertical eruption columns, which compares favorably with the accuracy of the common temperature method

Horváth, Ákos

Carr, James L.

Girina, Olga A.

Wu, Dong L.

Bril, Alexey A.

Mazurov, Alexey A.

Melnikov, Dmitry V.

Hoshyaripour, Gholam Ali

Buehler, Stefan A.

KITopen

Geometric estimation of volcanic eruption column height from GOES-R near-limb imagery-Part 1: Methodology

In a companion paper (Horváth et al., 2021), we
introduced a new technique to estimate volcanic eruption column height from
extremely oblique near-limb geostationary views. The current paper
demonstrates and validates the technique in a number of recent eruptions,
ranging from ones with weak columnar plumes to subplinian events with
massive umbrella clouds and overshooting tops that penetrate the
stratosphere. Due to its purely geometric nature, the new method is shown to
be unaffected by the limitations of the traditional brightness temperature
method, such as height underestimation in subpixel and semitransparent
plumes, ambiguous solutions near the tropopause temperature inversion, or
the lack of solutions in undercooled plumes. The side view height estimates
were in good agreement with plume heights derived from ground-based video
and satellite stereo observations, suggesting they can be a useful
complement to established techniques.</p