Comparison of Explosive Volcanic Eruptions with Effusive Volcanic Eruptions

	An Explosive Eruption	An Effusive Eruption	Extreme Explosive Eruption	Extreme Effusive Eruption
Volcano	Pinatubo (1991)	Laki (1783)	Yellowstone (2.059 Ma)	Siberian Traps (250 Ma)
Primary magma type	dacite	basalt	rhyolite	basalt
Duration of longest eruptive phase	9 hours	8 days	a few hours to days
Duration of emissions	5 days	8 months		670,000+ years
Volume of eruptives (DRE)	5 km³
Bulk volume of pyroclastic fallout	4 km³	0.4 km³
Dominant type of mass flow	ignimbrite	basaltic lava	ignimbrite	basaltic lava
Bulk volume of mass flow	6 km³	15 km³	2,450 km³	3 million km³
Area of mass flow	400 km²	565 km²	15,500 km²	5 million km²
Caldera formed	2.5 km diameter		75 km long 45 km wide
Eruption columns to	35 km	13 km
SO₂ emissions	17 Mt	122 Mt		7 Gt sulphur
H₂O emissions	491-921 Mt	235 Mt
Chlorine emissions	3-16 Mt	15 Mt
Fluorine emissions		7 Mt
Bromine emissions	11-25 kt
Maximum regional SO₂ concentrations	300 ppbm	1000 ppbm
Average effect on climate	up to -0.5^oC for 3 years		up to -4^oC for 6 years	+8^oC warming low-latitude sea surface
Warming of lower stratosphere	+3^oC within 5 months
Peak change in surface temperature	-0.7^oC	+3.3^oC in NW Europe	-10^oC for a few months
Northern continental winter temperature	+3^oC

Explosive eruptions are short-lived but form aerosols in the lower stratosphere that cool Earth. Extrusive eruptions last much longer, extruding much more magma, but inject little into the stratosphere. DRE is dense-rock equivalent. Data for Pinatubo from Self et al. (1996)), Scott et al. (1996), Gerlach et al. (1996), (Bureau et al., 2000) and (Robock, 2002); Laki from Thordarson and Self (2003); Yellowstone from Christiansen (2001), Lanphere et al. (2002), Jones et al. (2005) and (Segschneider et al., 2013); Siberian Traps from Reichow et al. (2009), Black et al. (2012), and Joachimski et al. (2012).