Explosive volcanic eruptions can produce sustained, buoyant columns of ash and gas in the atmosphere (Fig. 1). Large flood basalt eruptions may also include significant explosive phases that generate eruption columns. Such eruptions can transport volcanic volatiles to great heights in the atmosphere. Volcanic eruption columns can also redistribute chemical species within the atmosphere by entraining ambient atmosphere at low altitudes and releasing those species at much higher altitudes

Baloga, Steve

Glaze, Lori S.

Self, Stephen

Stofan, Ellen R.

NASA Technical Reports Server

VOLATILE TRANSPORT BY VOLCANIC PLUMES ON EARTH, VENUS AND MARS.  L. S. Glaze1, S. 
Self2, S. M. Baloga3, and E. R. Stofan3, 1NASA Goddard Space Flight Center (8800 Greenbelt Road, Greenbelt, MD 
20771; Lori.S.Glaze@nasa.gov), 2The Open University (Milton Keynes, UK, stephen.self@open.ac.uk), 3Proxemy 
Research (Laytonsville, MD, steve@proxemy.com; ellen@proxemy.com). 
 
 
Introduction:  Explosive volcanic eruptions can 
produce sustained, buoyant columns of ash and gas in 
the atmosphere (Fig. 1). Large flood basalt eruptions 
may also include significant explosive phases that gen-
erate eruption columns. Such eruptions can transport 
volcanic volatiles to great heights in the atmosphere. 
Volcanic eruption columns can also redistribute chem-
ical species within the atmosphere by entraining ambi-
ent atmosphere at low altitudes and releasing those 
species at much higher altitudes.   
Volcanoes and Climate:  The relationship between 
volcanoes and climate is complex and operates over a 
range of time scales, from days to possibly centuries. 
On Earth, volcanoes have long been associated with 
short-term local weather, and may influence longer-
term climate (see [1] and references therein).  Sulfur 
species (SO2 and H2S) are the primary volcanic vola-
tiles that impact climate. Sulfur dioxide is particularly 
important when injected into the stratosphere because 
the sulfuric acid (H2SO4) aerosols derived from SO2 
can have long residence times (1 – 2 years). By far the 
most important impact of increased stratospheric 
H2SO4 is increased backscatter at optical wavelengths, 
resulting in stratospheric warming and a net cooling at 
the surface, particularly in the summers following an 
eruption [1]. In addition, the 1991 Pinatubo eruption 
was linked directly to increased depletion of ozone 
through heterogeneous chemical reactions between 
volcanic aerosols and anthropogenic chlorine [2]. In 
some instances, complex atmospheric circulation can 
result in ‘winter warming’ in some continental regions 
following tropical eruptions [3]. Separating climatic 
variations due to volcanic eruptions and other periodic 
phenomena, such as El Niño or solar variability, can be 
a complicated process. The lack of oceans on Venus 
and Mars should simplify the interactions between 
volcanoes and climate, but there are still many un-
knowns in these environments, including magmatic 
volatile composition and levels of volcanic activity 
now and in the past. On Venus and Mars, where water 
is not as abundant as Earth, H2O may also be a key 
greenhouse gas supplied by volcanoes that has influ-
enced climate. 
Buoyant plume dynamics play an important role in 
the ability of explosive volcanic eruptions to supply 
climatically sensitive gases (e.g., H2O, SO2, CO2) to 
planetary atmospheres. The altitude at which these 
gases are injected into the atmosphere is controlled in 
large part by the composition and density of the ambi-
ent atmosphere. Thus, the dynamics of plume rise and 
ultimately the final rise height of a plume are strongly 
influenced by the ambient atmospheric properties.  
Models of volcanic plume dynamics are largely based 
on the original buoyant plume work of Morton et al. 
[4], and include models for axi-symmetric plume rise 
from circular vents [e.g., 5-7] as well as planar plumes 
from linear fissure vents [8,9].  
Earth.  Recent examples of large, historic, erup-
tions that have impacted climate on the 1–2 year time-
scale through the injection of large amounts of SO2 
into the atmosphere include Krakatoa (1883), Agung 
(1963), El Chichon (1982), and Pinatubo (1991; Fig. 
2). Despite widespread notoriety in the US, the erup-
tion of Mt. St. Helens (1980) was relatively small by 
both explosive standards and contribution of SO2.  The 
eruption of Laki (1783) [10] is an example of a sus-
tained fissure eruption that fed SO2 into the upper 
troposphere (and likely the lower stratosphere) through 
repeated eruptions over a period of eight months, af-
fecting weather in western Europe during the summer 
of 1783 and possibly through 1784 [11].  Volumes of 
SO2 injected by historic volcanic eruptions range from 
7 Mt (= 7 teragram) by El Chichon [12], to 20 Mt by 
Pinatubo [12], and up to an estimated 122 Mt by Laki 
[10]. In addition to SO2, volcanic eruptions on Earth 
are capable of redistributing large volumes of water 
from the lower atmosphere into the stratosphere. Mod-
els indicate that a 25 km plume erupting into a wet, 
tropical atmosphere, can transport up to 4 Mt of H2O 
Fig 1. Eruption of Mt. Pinatubo 3 days prior to the cat-
aclysmic eruption on 15 June 1991, that reached 35 km 
altitude. 
https://ntrs.nasa.gov/search.jsp?R=20120009611 2019-08-30T20:36:13+00:00Z
per hour to the plume top, ~30% of which is entrained 
in the lower atmosphere [6].  
Based on the impact observed following the Laki 
eruption, some have speculated that the large flood 
basalt eruptions (e.g., Columbia River Basalts, Deccan 
Traps) may have supplied large volumes of SO2 and 
other gases to the upper troposphere, or possibly even 
the stratosphere. The flood basalt lava fields are made 
up of multiple flow units that are estimated to have 
erupted with volumetric flow rates similar to the max-
imum estimated for Laki, each emplaced on decadal 
time scales [13].  Long duration effusive basaltic erup-
tions, such as the current 30 year eruption of Puu Oo, 
Hawaii, are consistent with flood basalt events that 
may have had more or less constant volume eruption 
rates over hundreds of years, injecting up to 1000 Mt 
of SO2 into the atmosphere for decades at a time.  [14] 
Venus.  Compared to Earth, it is extremely difficult 
to generate buoyant plumes under current atmospheric 
conditions on Venus [9, 15, 16]. This is due, in part to 
the relative densities of volcanic volatiles and the 95% 
CO2 atmosphere, at Venus surface temperatures 
(450°C) and pressures (92 bar).  In general, explosive 
eruptions on Venus would tend to generate collapsed 
columns and pyroclastic flows. However, when mag-
matic temperatures exceed 1100 °C, and when water is 
assumed to be the driving magmatic volatile, models 
predict that buoyant plumes can be sustained [16].  It is 
possible that Venus is still volcanically active [17], and 
observations of spikes in SO2 at the top of the tropo-
sphere may indicate current volcanism on Venus [18]. 
For boundary conditions producing a buoyant plume 
that can be sustained, models suggest that plumes may 
be able to rise to the top of the troposphere (70 km 
above the surface). Injections of volcanic SO2 of the 
order 250 MT/hr and H2O up to 2500 MT/hr could be 
injected into the cloud layer (Table 1).  Venus is 
thought to have possibly been resurfaced through a 
global volcanism 500 -750 Ma.  Such an event would 
have contributed huge amounts of H2O, SO2 and other 
volatiles into the atmosphere. 
Mars.  The key driver of plume buoyancy is the 
warming of entrained ambient atmosphere through 
convection.  Thus, the term ‘buoyancy’ loses its mean-
ing in the tenuous atmosphere on Mars where there 
simply is not enough atmosphere to entrain.  The cur-
rent low density atmosphere can sustain buoyant 
plumes up to heights of ~10 km, above which, ballistic 
transport likely dominates [19].  However, Mars may 
have had a somewhat warmer climate in the past with 
an atmospheric density similar to Earth (~1 bar).  If so, 
then explosive plumes on Mars would have been capa-
ble of injecting volatiles at altitudes of 30 – 40 km, 
similar to large pyroclastic eruptions on Earth.  For 
example, the Medussa Fossae deposit has been postu-
lated as being formed by large pyroclastic eruption(s) 
in the Hesperian (3000 – 3700 Ma) [20] 
References: [1] Robock, A. (2000) Rev. Geophys., 
38 (2), 191 - 219. [2] Solomon, S. et al. (1996) JGR, 
101, 6713 – 6727. [3] Robock, A., and Mao, J. (1995) 
J. Climate, 8 (5), 1086-1103. [4] Morton, B.R. et al. 
(1956) Proc. Roy. Soc. Lond. Series A, 234, 1-23. [5] 
Woods, A.W. (1988) Bull. Volcanol., 50, 169-193. [6] 
Glaze, L. et al. (1997) JGR, 102 (D5), 6099-6108. [7] 
Mastin, L. (2007) GGG, 8 (3). [8] Stothers, R.B. 
(1989) J. Atmos. Sci., 46 (17), 2662-2670. [9] Glaze, 
L.S., et al. (2011) JGR, 116 (E01011). [10] 
Thordarson, T., et al. (1996) Bull. Volcanol., 58, 205 - 
225. [11] Franklin, B. (1784) Manchr. Lit. Philos. Soc. 
Mem. Proc., 2, 122 (also Weatherwise, 35, 262, 1982). 
[12] Bluth, G.J.S. et al. (1992) GRL, 19 (2), 151-154. 
[13] Self, S. et al. (1998) Ann. Rev. Earth Plan. Sci., 
26, 81 - 110. [14] Self, S. et al. (2006)  Earth Plan. Sci. 
Letts., 248, 518 – 532. [15] Thornhill, G.D. (1993) 
JGR, 98 (E5), 9107 - 9111. [16] Glaze, L.S. (1999) 
JGR, 104 (E8), 18,899 - 18,906. [17] Smrekar, S.E., et 
al. (2010) Science, 328, 605 - 608. [18] Esposito, L. 
(1984) Science, 223, 1072 – 1074. [19] Glaze, L.S., 
and Baloga S. (2002) JGR, 107 (E10, 5086). [20] 
Kerber, L. et al. (2011) Icarus, 216, 212 - 220. 
Fig 2. SO2 emission seven days after Mt. Pinatubo 
erupted in 1991. Image curtsey NASA/Goddard Space 
Flight Center Scientific Visualization Studio. 
Table 1. Estimated rates of injection of H2O and SO2 at 
maximum plume heights on Venus, for magmas with 7 
wt% volatiles (70% H2O, 15% CO2, 8% N2, 7% SO2). 
Plume Height 
(km) 
H2O flux 
(Mt/hr) 
SO2 flux 
(Mt/hr) 
20 – 30 275 – 877 28 – 88 
30 – 40 620 – 1750 62 – 175 
40 – 50 1100 – 2630 110 – 263 


Volatile Transport by Volcanic Plumes on Earth, Venus and Mars

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