Eruption was Minimal: Evidence from the GISP2 Ice Core

Eruption was Minimal: Evidence from the GISP2 Ice Core

The University of Maine
DigitalCommons@UMaine
Earth Science Faculty Scholarship
Earth Sciences
11-1-1994
Climatic Impact of the A.D. 1783 Asama (Japan)
Eruption was Minimal: Evidence from the GISP2
Ice Core
G. A. Zielinski
R. J. Fiacco
Paul Andrew Mayewski
University of Maine, [email protected]
L. D. Meeker
S. Whitlow
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Repository Citation
Zielinski, G. A.; Fiacco, R. J.; Mayewski, Paul Andrew; Meeker, L. D.; Whitlow, S.; Twickler, M. S.; Germani, M. S.; Endo, K.; and
Yasui, M., "Climatic Impact of the A.D. 1783 Asama ( Japan) Eruption was Minimal: Evidence from the GISP2 Ice Core" (1994). Earth
Science Faculty Scholarship. Paper 191.
http://digitalcommons.library.umaine.edu/ers_facpub/191
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Authors
G. A. Zielinski, R. J. Fiacco, Paul Andrew Mayewski, L. D. Meeker, S. Whitlow, M. S. Twickler, M. S. Germani,
K. Endo, and M. Yasui
This article is available at DigitalCommons@UMaine: http://digitalcommons.library.umaine.edu/ers_facpub/191
GEOPHYSICAL RESEARCH LETTERS, VOL. 21, NO. 22, PAGES 2365-2368, NOVEMBER 1, 1994
Climatic impact of the A.D. 1783 Asama (Japan) eruption
was minimal:
Evidence
from
the GISP2
ice core
G.A.Zielinski,
R.J.Fiacco,
P.A.Mayewski,
L.D.Meeker,
S.Whitlow,
M.S.Twickler
GlacierResearchGroup,Universityof New Hampshire,Durham,New Hampshire
M.S.
Germani
McCrone Associates,Inc., Westmont, Illinois
K. Endo, M. Y asui
Departmentof EarthSciences,NihonUniversity,Tokyo,Japan
Abstract. Assessingthe climatic impact of the A,D. 1783 eruptionslike Laki versus more explosive plinian eruptions
eruptionof Mt, Asama, Japan,is complicatedby the concur- like Asama is lost becauseof the possiblecumulativeeffects
rent eruptionof Laki, Iceland. Estimatesof the stratospheric of the two eruptions. Thus, many studiesof the atmospheric
loadingof H2SO
4 for theA.D. 1108eruption
of Asamaderived effectsof volcanismin the mid-1780softenlump the Lald and
fromtheSO42'
timeseries
in theGISP2Greenland
icecorein- Asama eruptionstogether.
We presenthere a different approachto estimatethe amount
dicatea loadingof about10.4 Tg H2SO4 with a resulting
stratosphericoptical depth of 0,087. Assumingsulfur emis- of stratosphericloadingof the 1783 Asamaeruptionand ultisionsfrom the 1783 eruptionwere only one-thirdof the 1108 mately its potential climatic effects. By using the amountof
eventyieldsa H2SO4 loadingvalueof 3.5 Tg anda strato-
volcanically
derived
$O42recorded
intheGreenland
IceSheet
spheric optical depth of only 0.029. These results suggest ProjectTwo (GISP2) ice core for the 1108 Asamaeruptionand
minimal climatic effectsin the NorthernHemispherefrom the the relativemagnitudeof the 1108 and 1783events,we canes-
1783 Asamaeruption,thus any volcanically-induced
cooling
in the mid-1780sis probablydue to the Laki eruption.
timate
thestratospheric
loading
of I-IeSO
4 forthe1783Asama
eruption. All ice coresrecoveredfrom Greenlandarecharacterized by the presenceof a large volcanic signal around 1783
[e.g., Clausen and Hammer, 1988], but an estimate of the
Introduction
magnitudeof the signal that can be attributedto the Asama
Asama volcano (36.5øN, 138.9øE), Honshu, Japan, has eruption versus the proximal Laki eruption has not been
eruptedmany times over the last 1000 years [Aramaki, 1956; attempted.We will do that hereas well asprovideinformation
effectsof the 1108 eruption.
1957; 1963], but only two of theseeventshave been large on the atmospheric
Previous workers have approximatedthe amountof atmoenoughto definitely warrant a volcanic explosivityindex
(VEI) of at least 4 [Sirekin et al., 1981]. The earliest and most spheric loading of historical Asama eruptionsthrough the
explosiveevent was in September1108 (VEI = 5?) The more compositionof glass inclusionstrapped in phenocrysts(i.e.,
recent eventwasin May-August1783(VEI = 4). Despitethe petrologicmethod;[Devineet al., 1984]). Sulfuremissionesgreater volume of erupted material from the 1108 eruption timatesfor the 1108 event were 0.33 Tg resultingin an atmo-
[Ararnaki,1963],the 1783eventis probablythebest-known sphericloadingof 1 Tg H2SO4 by the petrologicmethod,
of theseeruptions. This notorietyis especiallydue to its un-
whereas sulfur emission estimates for the 1783 event were 0.1
loadingof 0.3 Tg H2SO4
certainclimaticeffectson the NorthernHemisphere.In fact, Tg resultingin an atmospheric
[Kohno
et
al.,
1993].
Thus,
the
atmospheric
loadingof the
directevidencefor the atmospheric
andclimaticeffectsof the
1108 eruption is thought to be about three times that of the
1783 eruption[Kohnoet al., 1993]. Unfortunately,the petrologic techniquemay underestimate
the amountof atmospheric
loadingof sulfur gasesfrom an eruptionpossiblydue to an un[Angelland Korshover,1985]andfromhistoricalandproxy known sulfur source (as was found after E1 Chich6n, 1982;
records [Mikami and Tsukarnura,1992; Wood, 1992] that cli- [Devine et al., 1984]). It is thus necessaryto comparethe
1783 Asama eruption is not easily obtained,becauseof its
timing in relationship to the lengthy Icelandic eruption of
Laki [June,1783-February,1784; Thordarsonand Self, 1994].
I t is well established both from instrumental records
of atmospheric
loadingestimated
by thepetrologi
c
maticconditions
duringthemid-1780s
weremuchcoolerthan amount
averageconditionsin the late 1700s. However,questions
may
arise regarding the magnitudeof climatic cooling due to the
method with that from other sources, like ice cores.
We analyzed the completesuite of major ions in bi-yearly
individualevents. In particular,importantinformationthat samples for the GISP2 core using ion chromatography
et al., 1993]. Highpeaksin SO42'andoccasionmay be usedto evaluatethe atmospheric
effectsof largefissure [Mayewski
ally in CI' are thoughtto be representativeof the depositionof
volcanically-derived aerosols [e.g., Mayewski et al., 1993].
Specificlaboratorytechniquesand the protocolusedto elimi-
Copyright
1994by theAmerican
Geophysical
Union.
natecontamination
givenin MayewSki
et al. [1993]. We also
filtered meltwatersamplesin the 1783/84 sectionin an at-
papernumber94GL02481
tempt to identify volcanic glasswith a scanningelectronmicroscopeand microprobe(seeFiacco et a/.,1993].
0094-8534/94/94GL-02481
$03.00
2365
i
Depth-agescalefor •thecorewasdetermined
by the counting
of annuallayers found in the physicalstratigraphyof the ice
, ,
, i
,,,
i,
,,
i,
i
, i
, i •
1201
(A)
Hekla
andof peaks in electricalconductivity,
laserparticulates,
and
•5•80.Datingerroris nowthought
to be 1%for thelast30,000
1104
.
80
ye•s of record[Meese
et al., 1994],butthisis a veryconser-
I
.
vativevalueanderrorsareprobably
muchlessthanthatfor the
last1• years
forwhich
weareconcerned.
There
isanaddi-
4O
ß
tional error of + two years becauseof the biyearly sampling
schemeusedand, •wemustalsoconsiderthe lag betweenthe
0
timeof the eruptionand depositionon the ice. Nevertheless,
o
wefeelthatwe mayaccurately
identifythevolcano
responsible for mostSignals
Overthelast1000years[Zielinski
et al.,
o
80
are from Sirnkinet al. [1981] and morerecentsupplements
[T.
Simkin and L. Siebert,personalcommunication].
To estimatethe amountof stratospheric
loading for each
4O
, I
,
(B)
120
of thevolcanic
sign•iin thebiyearly
sampling
is appropriate
forthegiveneruptioti'
AgeandVEI of alleruptions
discussed
1106
,,
1110
I ,
, , I
1114
, , , I
1118
, ,,
Lak,1783
Asama
1783
_
_
Asamaeruption,we usedthetechnique
of ClausenandHammer
ß
0
[1988]. ClausenandHammer [1988]analyzed
icecoresam-
'''l
1770
ples acrossGreenland for the concentrationof fallout from
the bomb materialdepositedon Greenlandoriginatedfrom the
1102
, ,
1994]. Subannualsamplingin some volcanic sections,like
for Laki [Fiacco et al., in press],haveverifiedthat the timing
bombtesting
in theearly1950sat lowlatitudes
(11øN)andin
theearly1960sathigh!.afitudes
(75øN).Because
thesource
of
• Asima
1108
, , , I , ,, i ,T, i , , , i , , ,
1098
'''['''[ß
1774
ß
1778
Year
'''
1782
IT
1786
''
1790
AD
Figure2. Volcanically-derived
S04•' associated
withindividual eruptionsfor twenty-yeartime periodsaroundthe (A)
of Asama.SO42valuesfrom
stratospheric
injectionof a knownmagnitudefrom a single 1108and(B) 1783eruptions
aboverobustsplinefit of originalSO42timeseries
pointsource,theyassumed
thatthestratospheric
transport
of residuals
volcanicaerosols
andeventualdePOsition
on theGreenland as presentedin Zielinskiet al. [1994].
Ice Sheet is similar
ing.
to that of material
from nuclear bomb test-
However the amount of bomb fallout recorded in
Greenland
fromlowlatitude
testing
Waslowerthanthatfrom Weused
themid-point
of these
twovalues
(i.e.,1.8x 109)to
high latitude testing indicating the loss of aerosolsduring
longertransport. To accountfor this lossa multiplierwas determinedto convert the concentrationof depositedmaterialon
the ice' sheetinto a global stratosphericloadingestimate. The
aver•agemultiplier for depositedmaterialin centralGreenland
estimatestratosphericloadingfor the mid-latitudeAsamavolcano. We also are assumingthat all transportto Greenland
from Asama eruptionswas stratospheric,which is probablya
valid assumption given the distance between sites. The
amount
of volcanically-derived
SO42'
usedin ourcalculations
variesfrom 1.2 x 109for a high-latitude
eruptionto 2.4 x 109 is equal to the residualabovea robustsplinesmoothingof the
for an equatorialeruption[Clausenand Hammer, 1988;p. 21].
Hekla
150
Results
1104
•
20
100
I
,-•
Wewereabletoidentify
peaks
in boththeSO42'
andCl'time
15
0
c•
5
1098
1102
1106
originalSO42'
timeseries
[Zielinski
et al., 1994].
1110
1114
1118
I
"
series for the 1108 Asama eruption, although the October
1104 Hekla (Iceland)eruptionis muchmoreprominent(Figure
1A). The presenceof the largeHekla signalprovidesa reliable
time-line [Meese et al., 1994] that supportsthe age of layers
in this section of core and thus the presence of Asama
aerosols. No other VEI > 4 eruptionsare known to have oc-
25 ,'-'
curred in the decade from 1100 to 1110 [Sirnkin et al., 1981].
There appearsto be almosta two-yearlag betweenthe eruption
150
20
gesting stratospherictransport and validating the use of
lOO
15
50
10
200
B
0
andSO42'
deposition
in Greenland
(i.e.,in 1110)further
sug-
Asama
1783
Clausen
andHarnrner's
[1988]technique.
A verylargeSO42'
i
1770
[ ,
, i
, , , i
1774
,
1778
Year
, , [
1782
AD
,,
, [ ,
1786
5
,,
1790
peak during the summerof 1784 representsaerosolsfrom the
Laki and Asamaevents(Figure lB).
Theamount
of volcanically-produced
SO42associated
with
eachAsama
eventis moreclearlyshown
by theplotof SO42'
residuals
(Figur•!2)thatwepreviously
developed
[Zielinski
et
al., 1994]. Residual value for the 1108 event is 14 gg/kg
(Table1). Notethatinourprevious
workweused
a SO42'
residual value of 25 gg/kg as the minimum value for a significant
Figure1. Timeseries
of SO42'
andCI' concentrations
from climate.forcingeruption. The large magnitudeof the 1783
bi-yearlYsamplesfor twenty-yearperiodsaroundthe largehis- signal(175 gg/kg) is clearly shown(Figure 2B).
Using these residual values we initially estimateda total
torical Mt. Asamaeruptionsof (A) 1108 and (B) 1783. Age
scaleis mid-summerfor year given. Age of samplescontain- stratospheric
loadingof H2SO4 for the 1108eventaswe feel
this signal may reflect deposition of only Asama aerosols
ing volcanicglassshownin (B) by arrowsA-C.
Table 1. Estimates
of Stratospheric
MassLoadingof
HeSO
4andOpticalDepthforA.D. 1108andA.D. 1783
Eruptionsof Mt. Asamafrom the GISP2 Ice Core
1108
1783
Volcanic
SO4•-'(pg/kg)
14
Volcanic
SO••- Flux(x103kg/km2)
* 5.8
Stratospheric
Loading
H2SO,•
(Tg)& 10.4
Total Stratospheric
Loading(Tg) #
13
Stratospheric
OpticalDepth(XD)•
0.087
LI li;I.L
•, 1,1111,11
_[JIUUU•,LIUII
4.7*
2.0
3.5
4.3
0.029
11UIII
! OO
eruptionis one-thirdthatof the 1108eruption.
*Product
of volcanic
SO,,
2-,length
oficeandicedensity
&Product
of volcanic
SO42fluxanda multiplier
of 1.8x 109
for a mid-latitude
eruption.Seetextfor explanation.
#Composition,
byweight,
of H2SO,,
aerosol
particles
is
roughly
75%I-I2SO,,
and25%H20. Selfetal. [inpress]
used
1.25 asan averagemultiplierto convertto totalloading.
•Determined
fromrelationship
definedby Stothers
[1984],
stratospheric
massloading
(MD)=1.5x 10•'*xDg.
Furthermore,the large signal around1783 found in ice cores
from Greenlandis mostlikely almostentirelydue to aerosols
from Laki. Even if sulfur depositionfor the 1108 and 1783
eruptionswere essentiallyequal, a volcanicflux of 5.8 gg/kg
(Table 1) is an orderof magnitudelessthanthe 57 gg/kg flux
that we calculatedfrom biyearly samplesfor the total 1783
signal.Estimates
of thestratospheric
loading
of H2SO,,
forthe
Laki eruptionrangefrom about100 to 200 T g [e.g.,Palais and
Sigurdsson, 1989; Clausen and Hammer, 1988]; estimates
from Greenlandice coresare complicatedbecausethere is a
trnpn•pheric component contributing to the Laki signal.
Nevertheless,we concludethat mostvolcanically-induced
climatic and atmosphericphenomenaduring the mid-1780swere
due to the Laki eruption.
One potentialbias that we mustaddressis any differencein
the polewardtransportof Asama aerosolsdue to seasonof the
eruption(May 1108 versusAugust 1783) that couldresult in
under-representation
of 1108 aerosoldeposition. However,
we do not feel thatis a problembasedon previousatmospheric
studiesrelated to the May 1980 eruptionof Mt. St. Helens.
McCormick and Trepte [1987] detectedan increasein strato-
sphericopticaldepthin the Arcticthreemonthsaftertheerup(Table1). Ourestimate
for the1108eventis anorderof mag- tion suggestingvery quick transportto polar regionsfrom
nitudegreaterthan that derivedfrom the petrologicmethod this mid-latitudeeruption. Quick transportwould limit the
[Kohnoet al., 1993]. Rampinoand Self [1984] showedthat
stratospheric
loading estimatesfrom the petrologicmethod
are often an order of magnitudeless than that from optical
depthandice corecalculations.Usingour loadingnumbers
we
thencalculatedthe potentialstratospheric
loadingof the 1783
Asamaeruption(Table 1) assuming
thatsulfurproduction
from
the 1108eruptionwasthreetimesgreaterbasedon petrologic
analyses[Kohnoet al., 1993]. Finally,we suggest
thepoten-
tial stratospheric
opticaldepth(XD)for eacheruption
giventhe
massloadingsthat we calculatedin Table 1.
amountof loss, althoughthere could still be someloss in the
two yearsprior to deposition. The multiplierinvokedby
Clausenand Hammer[1988] shouldaccountfor any aerosol
lossin the polarregionsprior to deposition.Interestingly,
SO,,2' levelsin themid-1780s
returnto background
levelsby
early 1785 [Fiaccoet al., in press]meaningeitherquicker
transport and deposition of aerosols from the 1783 Asama
eruptionor very little (if any) depositionin Greenland.
To furthersubstantiate
our suggestion
thatthe 1783 Asama
eruptionhad very little climaticimpact,we evaluatedthe cli-
We foundvolcanicglassin severalsamplesfrom the 1783
sectionof core includingbasalticshardsthat are similar to
thatfrom theLaki eruption[GlassC, FigureslB and3; Fiacco
et al., in press]. A high-alkaliandesiticto daciticglasswas
matic effectsof the 1108 eruptionby compilingproxydata
pled layers from 1110.
Similarly,thereare no recordsof climaticcoolingfollowing
1108 in Germanoak chronologies
[Lamb,1977; p. 595-602],
(e.g., tree-ringrecords)aroundthe 1108 time period. If minimal evidence of climatic cooling exists in the Northern
Hemispherefollowing the 1108 event then intuitively the
foundon two filters corresponding
to layersfrom early in 1783 eruptionwouldhavehad essentiallyno hemispheric
ef1783 (GlassB; FigureslB and 3) and late in 1784 (GlassA; fects. In fact, this is just the case. The only suggestion
of
FigureslB and 3). The composition
of theseshardsdo not climaticcoolingaround1108,particularlyin Europe,is a rematchglassfrom the plinianportionof the eruptionandonly constructed summer temperature minimum in 1109 from
tree rings,a value that is the secondcoldestover
a few shardsfrom the pyroclasticflow component
overlap Fennoscandia
with the compositionof GISP2 particles(Figure 3). Glass the 1500-yearrecord[Briffa et al., 1990]. However,a refinewith 62-64% silica hasyet to be foundin Laki deposits(K. mentof the technique[Briffaet al., 1992]failedto place1109
Grtnvold,personalcommunication).We havenot yet sam- in the top five coolestsummersover that sametime span.
20
Discussion and Conclusions
Our estimations
of I-I2SO,•loadingfor the 1783and1108
(Table1) Asamaeruptions
rangebetween
3 and10Tg withresultingxD valuesof 0.029and0.087,respectively.
Thesevalues are low comparedto direct measurements
for more recent
15
ß
Glass
ß
Glass
A
B
ß
Glass
C
O Asama
Pl•nlan
O
O
•
Asama
Pyroctast•c
lO
Frow
eruptions
overthelastcoupleof centuries
knownto haveperIo
turbedclimate(e.g., 0.10-0.15 for E1 Chich6n),although
massloadingandxD for the 1108eruptionis similarto, or
slightlygreaterthanNorthernHemisphere
valuesin the mid(•o
,,,,I,,,,i,,,,i,[,,[,,[,l[,,,i,,],
1960sthatmay includethe Agungeruption[Rampino
et al.,
50
60
70
80
1988;Satoet al., 1993]. Thus,sulfurloadingfromthe 1783
Si02
eruptionof Asamaprobablywasnot of sufficient
magnitude
(XD=0.029)to inducemajorclimaticcoolingin the Northern Figure 3. Covariationplot of volcanicglassfoundin the
Hemisphere.Estimatesof stratospheric
opticaldepthsfor 1783/84section
of theGISP2coreascompared
to therangein
most climatically-forcing volcanism since A.D. 1850 are composition
of glassshards
frombothplinianandpyroclastic
much greaterthan 0.02-0.03 [Figure 1 in Sato et al., 1993]. flow deposits
of the 1783Asamaeruption.
2368
ZIELINSKI
ET AL.: CLIMATIC
IMPACT OF A.D. 1783 ASAMA ERUPTION
in Irish and Scottish oaks [Baillie, 1977], nor in Bristlecone
pine recordsof America[LaMarcheand Hirschboek,1984].
We do not want to say, however, that Laki was the sole
eruption responsiblefor climatic perturbationsin the mid1780s. Benjamin Franklin, in his pioneeringwork linking
volcanic eruptionsto climate over 200 years ago, indicated
that severaleruptionsmay have contributedto the dry fog observed in Europe during the summer of 1783 [quoted in
Sigurdsson,1982]. Wood[1992] notedthe appearance
of dry
fog in Europe and of cooler and wetter conditionsin Japan
prior to either the Laki or Asamaeruption. He alsoconcluded
that there may have been anothereruptionearlier in 1783 that
contributedto atmosphericconditionsat that time. The appearanceof glassin the GISP2 core that is predominantly
outside the known compositionalrange of Asama and Laki glass
(Figure 3) could supportthe presenceof anothereruption.
Acknowledgments. We thank the Polar Ice Coring Office and the
109thAir NationalGuardfor logisticalsupport.T. Simkin,M. Rampino
andan anonymous
reviewermadebeneficialcomments.This workwas
supportedby the Office of Polar Programs,National Science
Foundation.
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