Maya Climate Geology Methods Results Discussion
Maya and Climate
Climate and the Collapse of Maya Civilization
Peter Barmet, Thomas Kuster, André Welti
Department of Environmental Sciences
ETH Zürich
Climate History and Paleoclimatology, 24.11.2006
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Maya Climate Geology Methods Results Discussion
Outline
1
Maya civilization
Geography
Culture
History
2
Climate
ITC
3
Geology / Hydrology
4
Methods
Gypsum (CaSO4 ) Deposition
Oxygen Isotops (δ 18 O)
Titanium Content
5
Results
6
Discussion
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Maya Climate Geology Methods Results Discussion
Geography Culture History
Geography (Middle America)
→ Lake Chichancanab
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Maya Climate Geology Methods Results Discussion
Geography Culture History
Geography (Yucatán Peninsula)
Areas
north
central
south
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Maya Climate Geology Methods Results Discussion
Geography Culture History
Architecture
Buildings
pyramids and temples
observations
ball courts
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Maya Climate Geology Methods Results Discussion
Geography Culture History
Architecture
Temple
Tikal
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Maya Climate Geology Methods Results Discussion
Geography Culture History
Architecture
Buildings
pyramids and temples
observations
ball courts
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Maya Climate Geology Methods Results Discussion
Geography Culture History
Architecture
Ball Court
Monte Albán, in the Oaxaca region of Mexico
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Maya Climate Geology Methods Results Discussion
Geography Culture History
Ballgame
Ballgame
resemble volleyball
with ritual association (winners or losers are sacrificed)
staked themselves (ending up as slaves)
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Maya Climate Geology Methods Results Discussion
Geography Culture History
Periods
Preclassic
2000 BCa to 250 ADb
first settled villages along the Pacific coast
ceremonial architecture (1000 BC)
a
b
Before Christ
Anno Domini, latin for "in the year of the lord"
Classic
250 to 900 AD
city-centered empire consisting of independent city-states
zenith of the civilisation (800 AD)
Postclassic Period
900 to 1511 AD (spanish colonial period began)
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Maya Climate Geology Methods Results Discussion
Geography Culture History
Collapse
Collapse
estimated popullation before the collapse 3 – 13 million
between classic an postclassic period, in 3 phases
760 to 810 AD
to 860 AD
to 910 AD
different theories
limited farmland, soil degradation (Bodenverarmung)
disaster
war (invasion)
epidemic
climate (drought)
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
x
z
Naachtun
Geography Culture History
G
Ed
Chichén
Itzá
SCHWERPUNKT ARCHÄOLOGIE: MEERESSEDIMENTE
La Honradez
Uaxactún
Palenque Bucht
l von
�
Naranjo
Uxmal
Tikal
Campeche
Nakum
Piedras Negras
Tayasal
Yaxhá
ChichancanabOxpemu
Yaxchilán
lf f
Polol
o
See
Ucanal Caracol
G l
Noch ist dies ein sehr neuer Ansatz, doch
o
Calakmul
er brachte in den letzten Jahren immer
G
AreasErkenntnisse.
and Time
of
EdznaSeibal
wieder verblüffende
Zum
Beispiel verraten auch Analysen von
Naachtun
Baumringen
im amerikanischen
SüdwesCollapse
Time
ten, dass dort zwischen 1275 und 1300
Machaquilá
eine ausgeprägte Trockenheit herrschte –
810 AD
möglicherweise eine Ursachecentral:
für das Verht von
schwinden der Anasazi, eines durch seine
ri
in die Steilwände
des Colorado-Plateaus
b
Palenque
south: 860 ADUaxact
ik
mpeche
gebauten Pueblos bekannten Indianervolks (siehe den Beitrag auf S. 56).
Der Zusammenbruch des
Akkadi- 910 AD
Ti
north:
schen Reichs inNegras
Mesopotamien vor 4200
Jahren, der Niedergang der Mochica-KulOxpemul Piedras
Tayasa
tur an den Küsten Perus vor 1500 Jahren
und das Ende der Tiwanaku-Zivilisation
La
Muñeca
Yaxchilán
im
Hochland
Boliviens
und
Perus
vor
eiCalakmul
Polol
nem Jahrtausend – all diese EntwicklunPa
gen lassen sich heute mit lang andauernzi
fi
den Dürren in Verbindung bringen. Mök
Copán
Naachtun
Seibal
gen auch in allen diesen Fällen noch
Me
Maya Climate Geology Methods Results Discussion
Der amerikanische Archäologe
Richardson B. Gill postuliert, dass
der Untergang der klassischen Mayakultur in drei Phasen verlaufen sei. Um das
Jahr 810 (grün) seien die ersten Städte
verlassen worden, etwa 50 Jahre später
folgte die nächste Phase (braun), um 910
dann die dritte (blau).
Me
vo
n
xiko
Collapse
Chichén Itzá
vo
n
Uxmal
ChichancanabSee
Edzna
Bucht von
Campeche
Oxpemul
Calakmul
Naachtun
Palenque
Machaquilá
Copán
andere Faktoren eine Rolle gespielt haben
– Kriege, Überbevölkerung, Umweltzerstörung –, so hatte doch stets eine KlimaEntwaldung und Übernutzung landwirt- rum manche Gesellschaften überleben verschlechterung entscheidenden Anteil
Barmet,
Thomas
Kuster, André Welti
Maya
Climate
schaftlicher Flächen Peter
sogar zerstörte.
Hinoder untergehen«.
am and
Untergang
früher Hochkulturen. Und
P
SON GILL
EMDE-GRAFIK / SPEKTRUM DER WISSENSCHAFT, NACH: RICHARDSON GILL
La Honradez
Naranjo
Tikal
Nakum
Tayasal
Yaxhá
Polol
Ucanal Caracol
Seibal
a
Yaxchilán
Uaxactún
K
Piedras Negras
La Muñeca
Uaxactún
La Honradez
M
Maya Climate Geology Methods Results Discussion
Geography Culture History
Collapse
Collapse
estimated popullation before the collapse 3 – 13 million
between classic an postclassic period, in 3 phases
760 to 810 AD
to 860 AD
to 910 AD
different theories
limited farmland, soil degradation (Bodenverarmung)
disaster
war (invasion)
epidemic
climate (drought)
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Maya Climate Geology Methods Results Discussion
ITC
Inter Tropic Conversion (ITC)
Abbreviations
ITC: Inter Tropic Conversion
ITCZ: Intertropical Convergence Zone
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Maya Climate Geology Methods Results Discussion
ITC
Functionality
Inter Tropic Conversion (ITC)
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Maya Climate Geology Methods Results Discussion
ITC
Functionality
Hadley Cell
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
ITCZ is located at its southernmost position
time span often termed the Medieval Warm
Mayawinds
Climate
Results
and trade
along theGeology
VenezuelanMethods
coast
Period.
BeforeDiscussion
the sharp Ti rise at ITC
⬃1070 yr
are strong. In contrast, dark laminae are deB.P. (930 A.D.), sediment Ti concentrations
posited during the regional rainy season
were of intermediate value, with the excep(summer-fall), when the ITCZ migrates to its
tion of pronounced minima centered in our
ITC over Middle America
Influence
most of rain (90%)
during summer
dry winter
southward
displacement of the
ITC → drought
north–south
precipitation
gradient (Yucatán
peninsula)
south: 4 000 mm
north: 500 mm
Fig. 1. Seasonal variations in the mean position of the ITCZ over Mesoamerica and northern South
America, illustrated for typical summer (September) (top) and winter (March) (bottom) conditions.
Peter
Barmet,
Thomas
Kuster,
André
Welti
These variations control the
pattern
and timing
of regional
rainfall.
Numbers
and colorsMaya
reflect and
sea Climate
Maya Climate Geology Methods Results Discussion
Sectional Drawing through the Yucatán Peninsula
langen
expliziVeränin der
n. Ein
nd der
ner auf
der sie
fahren,
n unter
Fall zu
adurch
besonGehalt
mmen,
hlamm
onzentHinweis
itangeeffektiv
m ohne
chemihätte.
reszenz
Material
Küstenebene
von Campeche
z
Küstenebene
von Yukatan
Golf von
Mexiko
Süden
Norden
STEPHANIE FREESE, NACH: RICHARDSON GILL
OGIE: MEERESSEDIMENTE
sprechen dafür, dass der Kollaps der Ma- dings lassen sich diese Sedimentschichten
yazivilisation sowohl räumlich wie zeit- nicht ganz genau datieren. Radiokarbonlich unterschiedlich verlief. Wenn Tro- messungen legen sie auf die Jahre 760,
ckenheit ein entscheidender Grund des 810, 860 und 910 fest, doch mit einer
Niedergangs gewesen war, dann musste Ungenauigkeit von dreißig Jahren.
sie die verschiedenen Zentren zu unterDie Archäologen sind sich darin eischiedlichen Zeiten betroffen haben, ei- nig, dass der Niedergang der Maya im
nige wenige im Norden der Halbinsel südlichen und zentralen Tiefland YukaMaya
möglicherweisePeter
auch Barmet,
gar nicht.Thomas Kuster,
tansAndré
seinenWelti
Anfang nahm
undand
erstClimate
hun-
Overview
limestones
rocks and
mountains
caves (as in
the jura
mountains)
Maya Climate Geology Methods Results Discussion
Karst Cave with Groundwater
In der Küstenebene von Yukatan
erlauben eingestürzte Karsthöhlen
mitunter, an den Grundwasserspiegel zu
gelangen. Der Stich einer Expedition von
1844 zeigt, wie schwierig und gefährlich
so ein Unterfangen oft war. Je weiter
landeinwärts aber eine Siedlung angelegt
wurde, desto tiefer lag der Grundwasserspiegel, wie die Grafik links verdeutlicht.
l
Groundwater
access to groundwater is
rare
mehr Jahre dauernde schwere Dürre
überzugehen. Das entspricht dem Ende
der ersten »Gill«-Phase um 810. Damals
verließen die Maya die Zentren des westlichen Tieflands, wo es kaum Zugang zu
Grundwasserreservoiren gibt.
groundwater access is
importend factor for a large
population to survive
Elite ohne Weitsicht
Auch das Ende der zweiten Phase spiegeln die Meeressedimente durch einen
sehr niedrigen Titangehalt über drei bis
vier Jahre. Damals traf es die Siedlungen
des südöstlichen Tieflands. Vielleicht
hatten die Menschen dort dank einiger
Frischwasserlagunen (in denen Grundwasser austritt) die erste Phase überstehen können, doch nun waren diese Vorkommen wohl erschöpft.
Schließlich markiert ein starker Rückgang der Titankonzentration in unseren
Proben für die Zeit um 910 den endgültigen Kollaps am Ende des dritten Zeitabschnitts. Damals gingen auch die Städte des zentralen und des nördlichen Tieflands zu Grunde. Unseren Messungen
nach dauerte diese Dürre immerhin fünf
die zweite und die letzte schließlich bis
Gills Argumente wurden in Fachkrei- bis sechs Jahre. Erst danach stieg der Ge910 –, wobei es regional deutlich unter- sen heftig diskutiert. Breite Ablehnung halt an unserem Indikator Titan wieder
Peter Barmet,
Kuster,
Welti
Mayaerreichten
and vermutClimate
schiedliche Ausprägungen
gab. Diese Thomas
erfuhr beispielsweise
seine André
Annahme, die
an, die Regenmengen
WHITE STAR / FREDERICK CATHERWOOD
Maya Climate Geology Methods Results Discussion
Gypsum Deposition δ 18 O Titanium Content
Methods
Sediment Core Analysis
gypsum (CaSO4 ) deposition
oxygen isotops (δ 18 O)
titanium content
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Maya Climate Geology Methods Results Discussion
Gypsum Deposition δ 18 O Titanium Content
Gypsum (CaSO4 ) Deposition
Where?
Cores from Lake Chichancanab
Why are Sediments from Lake Chichancanaba good Archives?
closed basin that loses a large fraction of its water by
evaporation
CaSO4(aq) concentration near saturation
fallout of CaSO4 if saturation is reached trought height
water evaporation during droughts
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Maya Climate Geology Methods Results Discussion
Gypsum Deposition δ 18 O Titanium Content
Lake Chichancanab
ARTICLE IN P
D.A. Hodell et al. / Quaternary Science R
ARTICLE IN PRESS
D.A. Hodell et al. / Quaternary Science Reviews 24 (2005) 1413–1427
22˚ N
21˚ N
Punta Laguna
Chichancanab
20˚ N
19˚ N
18˚ N
92˚ W
91˚ W
90˚ W
89˚ W
88˚ W
87˚ W
ocation ofLocation
Lakes Chichancanab
and
Punta Laguna on the
Yucatan
relative
to contours
of annual rainfall in mm.
of Lakes
Chichancanab
and
PuntaPeninsula
Laguna
on the
Yucatán
Peninsula
Yucatan Peninsula during the period of Maya occupabability). Gypsum precipitation during the
Fig.
2.Terminal
Bathymetry
Lake Chichancanab
the position
Positon
of theof depth
transectshowing
of cores
(whiteof the
tion, including the events comprising the
assic Period suggested a period of drought
depth transect of cores taken in 2004 (white squares). Inset map shows
squares)
Classic Drought (TCD). This fine-grained that
paleoclimatic
-central Maya lowlands.
Lake Chichancanab is part of a chain of narrow lakes that are
history will help archaeologists evaluate connected
the roleduring
that high water levels.
we retrieved cores from 11 m of water in
climate change may have played in Maya cultural
ab that permitted us to refine our paleocliThomasevolution.
Kuster, André Welti
Maya and Climate
retations (Hodell et al., Peter
2001). Barmet,
Two cores
su
wa
lak
to
be
Yu
reg
low
pe
rel
ev
is
pa
wh
sa
ca
bo
ca
Su
an
be
Ch
by
av
mi
sa
th
ba
an
Co
va
19
3.0
d1
Maya Climate Geology Methods Results Discussion
Gypsum Deposition δ 18 O Titanium Content
Gypsum (CaSO4 ) Deposition
Where?
Cores from Lake Chichancanab
Why are Sediments from Lake Chichancanaba good Archives?
closed basin that loses a large fraction of its water by
evaporation
CaSO4(aq) concentration near saturation
fallout of CaSO4 if saturation is reached trought height
water evaporation during droughts
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
We were especially interested in the interval between
demise. Digital images of this time interval
showing a se
display strong gypsum/organic bands that were deposcolored gypsum layers interbedded with
4 Classic Periods when
ited during the Late and Terminal
sediments containing shells (Fig. 5). Shel
the Maya civilization reached its apex and ultimate
minantly gastropods (Pyrgophorus corona
pear in the images as white specks agai
organic-rich sediment. The digital images w
Gypsum
Deposition
for their red,
green, and blue compon
red/blue ratio (R/B) was used to assess th
Series
ofsplit
lightcolored
among the
core images (Fig. 6). T
of light-darklayers
alternating beds are identifie
gypsum
A, B, and C), and are separated from
interbedded
with dark, organic-r
by intervals of uniformly
Within each group
from a core, indi
organic-rich
sediments
can be recognized and are designated
containing
shells
and C1-2.
Density records among the cores are also
though subtle differences exist (Fig. 7).
Method
the two cores taken on 7 March 2004
interval
of low-density between
radiocarbon
date groups A a
cores taken
on 8 March 2004 contain
14
C) ofgroups
shellA and B. Noneth
peaks (between
and color
data for
four cores cle
material
andallwood
deposition of organic-rich sediments betw
and B.digital color linescan
Fig. 5. Images of four split cores taken at the same station in 14.7 m of
A radiocarbon date was obtained from
camera
water. Sediments are composed of interbedded gypsum and organiccore CH1 08-III-04-MWI-2 on wood foun
rich strata containing abundant shell material. The similarity of the
of
141–142
cm. The age was 1130735 1
cores indicates that sediments were not disturbed during the coring and
equivalent to 780–1000 AD using OxCal ve
splitting process. Arrow in Core CH1 08-III-04-MWI-2 designates
14
Peter Barmet,
Thomas Kuster,
André
the atmospheric data from Stuiver et al. (1
position of radiocarbon
date (1130735
C years
BP;Welti
780–1000 Maya
AD). and Climate
18
Maya
Geology
Methods
Results cores
Discussion
Gypsum Deposition
O Titanium
Content
120Climate
and 170
cm in the
deep-water
because they
sectionsδ are
very similar,
Gypsum (CaSO ) Deposition
Maya Climate Geology Methods Results Discussion
Gypsum Deposition δ 18 O Titanium Content
Oxygen Isotops (δ 18 O)
Where?
Cores from Lake Chichancanab
Detection of Drought Periods with δ 18 O
δ 18 O is a proxy for evaporation
enrichment of 18 O during droughts, because 16 O
evaporates easier
isotopic signal is conserved in shells
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Gypsum Deposition δ 18 O Titanium Content
Maya Climate Geology Methods Results Discussion
ARTICLE IN PRESS
18
Oxygen
Isotops (δ
O)
1424
D.A. Hodell et al. / Quaternary Science Reviews 24 (2005) 1413–1427
δ18O Cytheridella ilosvayi (‰, PDB)
-1.5
-1
-0.5
0
0.5
1
1.5
+
Analysis of δ 18 O
A
900
B
Classic
800
late
700
C
+
early
600
500
1
1.2
1.4
1.6
high evaporation
rates are indicated
by high δ 18 O
drought periods
(shaded in figure)
terminal
1000
Date (AD)
early
1100
Postclassic
1200
1.8
Density (g/cm3)
Fig. 14. Comparison of the GRA bulk density record from
Chichancanab Core
CH1
7-III-04
(solid
line) André
and the
5-pt running
Peter
Barmet,
Thomas
Kuster,
Welti
Maya and Climate
dated by
radiocarbon (14 C)
density
meassurements to
correlate different
sediment cores
Maya Climate Geology Methods Results Discussion
Gypsum Deposition δ 18 O Titanium Content
Titanium Content
Where?
Cores from Cariaco Basin
Why is Cariaco Sediment a good Proxy for Precipitation?
anoxic
undisturbed sediment
reflects variations in riverine input and the hydrological
cycle over northern tropical South America
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
he lowlands of the Yucatan
ITCZ is located at its southernmost position
Maya Climate Geology
Methods Results Discussion
1). Our data show a clear link
and trade winds along the Venezuelan coast
hronology of regional drought
are strong. In contrast, dark laminae are dee of Classic Maya culture.
posited during the regional rainy season
focused on the Holocene sedi(summer-fall), when the ITCZ migrates to its
recovered in Ocean Drilling
P) holes 1002C and 1002D
5°10.18⬘W; water depth, 893 m)
Basin (2). These rapidly deposper thousand years) organic-rich
visibly laminated and devoid of
hic faunas, indicating anoxic
onditions and no disturbance
g. As an index for regional hyions, we used the bulk titanium
a recorder of terrigenous sedito the Cariaco Basin from the
atersheds (3, 4). Previously re4) for the past 2000 years from
ig. 2, bottom) were obtained at
ment intervals (⬃4 to 5 years)
he accelerator mass spectromege model for these data and the
calendar years can be found in
dy, we subsequently analyzed a
mple from accompanying hole
igh resolution (50-␮m measure(5). Offset scans along the face
cated that the hole 1002D data
ble at the 50-␮m level, which is
observations that the laminae
. In the interval of hole 1002D
30-cm slab sample was taken,
Cariaco Basin
Earth Sciences, 2Department of
, CH-8092 Zürich, Switzerland.
ol of Marine and Atmospheric Sciof Miami, Miami, FL 33149, USA.
Geosciences, Princeton University,
544, USA. 5Department of Marine
eochemistry, Woods Hole Oceanon, Woods Hole, MA 02543, USA.
time span often termed the Medieval
Warm
Gypsum Deposition δ 18 O Titanium Content
Period. Before the sharp Ti rise at ⬃1070 yr
B.P. (930 A.D.), sediment Ti concentrations
were of intermediate value, with the exception of pronounced minima centered in our
Fig. 1. Seasonal variations in the mean position of the ITCZ over Mesoamerica and northern South
America, illustrated for typical summer (September) (top) and winter (March) (bottom) conditions.
Barmet,
Thomas
Kuster,
André
Maya
and Climate
These
variations
control
the pattern
andWelti
timing of regional
rainfall.
Numbers and colors reflect sea
spondence should be addressed.Peter
E-
Maya Climate Geology Methods Results Discussion
Gypsum Deposition δ 18 O Titanium Content
Titanium Content
Where?
Cores from Cariaco Basin
Why is Cariaco Sediment a good Proxy for Precipitation?
anoxic
undisturbed sediment
reflects variations in riverine input and the hydrological
cycle over northern tropical South America
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
R 2006
Titan (in Prozent)
Klima
16
0
6
47
3
20
42
8
40
40 Jahre
60
trocken
80
Tiefe in der Bohrkernprobe (in Millimetern)
less titanium → less
precipitation
nass
0,15
0
Titanium Content
titanium content is a
proxy for
precipitation
Klima
Titan (in Prozent)
0,30
0
100
corresponds to the
collaps of maya
civilisation
trocken
300
200
Tiefe in der Bohrkernprobe (in Millimetern)
0,30
nass
Kleine Eiszeit
Klima
tration
s Cariger Rewieder.
obalen
tzeiten
, aber
aya, ja
Kollapäologe
0,15
0
Titan (in Prozent)
in aufhellen
prung
nd der
ringen
stoffen
s OzeNordüstenh das
Algen
bezieen diere fesn jene
eichen
enaufuhr für
δ 18 O Titanium Content
STEPHANIE FREESE
t dort Maya
ser, der auch
für Yukatan
gilt, denn beide
BeckensResults
aufbrach. Den
Technikern ge- Gypsum Deposition
Climate
Geology
Methods
Discussion
m Meedie bei
fwüh~ 910 v. Chr.
~ 860 v. Chr.
~ 810 v. Chr.
~ 760 v. Chr.
0,30
nass
nderen
Sedieckens
0,15
mittelalterliche
Wärmeperiode
0
0
500
Kollaps der klassischen Mayakultur
1000
Alter der Sedimente (in Jahren)
1500
Peter Barmet, Thomas Kuster, André Welti
trocken
2000
Method
If titanium is irradiated
with X-ray, it emits at
specific wavelenght.
45
Maya and Climate
Maya Climate Geology Methods Results Discussion
Results
5 500 BC –
475 BC –
relative wet
drought period (before the rise of Maya
civiliation)
250 BC –
150 BC wet
150 BC –
250 AD drier period
250 AD –
600 AD good climate conditions
begin of a long dry period
600 AD
–
850 AD begin of the TCD, worst drought since the
760 AD
last 7 000 years
zenith of the drought and collapse of the
800 AD
civilization
990 AD second drought period
910 AD –
1 100 AD third drought period
1 060 AD –
⇒ period 800 to 1 000 AD was the driest of the middle to late
Holocene. This matches the period when the classic Maya
civilisation collapsed.
500 BC
250 BC
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
on between drought and
Maya Climate Geology
has been
demonstrated in
rds from equatorial east
e past 1100 years (26).
by which changes in solar
Results
tion (29). Sensitivity experiments conducted
with atmospheric general circulation models
imply that changes in solar output may affect
global mean temperature, humidity, convection,
and intensity of Hadley circulation in the trop-
Methods Results Discussion
on of
␦18O
Punta
(16),
ensity
canab
␦18O
E/P
ncide
proused,
solar
nd W
under,
nspot
y. (B)
tered
⌬14C
(34),
Lake
line)
bulk
Lake
line).
d component of ␦18O is in phase with inferred solar variability (or 180° out of
duction) for the last 1500 years. The 208-year component of the Punta Laguna
nab density signals are in phase between 0 and 1200 A.D.
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Cycle
Droughts cycle
shows a
periodicity of 206
years which could
be forced by the
solar cycle (solar
cycle 208 years).
drought
(δ 18 O)
solar cycle
(∆14 C)
Maya Climate Geology Methods Results Discussion
Discussion
Questions
between the very dry periods there were about 50 years of
less dry times, put Maya civilisation couldn’t regenerate
during them.
last drought didn’t correspond to the last collapse period
solar radiation differs only a little during the solar cycle
(1h). How can the big impact on the precipitation be
understood.
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Appendix
List of figures Bibliography
List of figures I
Yucatan Peninsula
Google Earth
Map showing the extent of the Maya civilization
http://en.wikipedia.org/wiki/Image:
Mayamap.png
Temple
http://en.wikipedia.org/wiki/Image:
Tikal6.jpg
Ballcourt
http://en.wikipedia.org/wiki/Image:
12-05oaxaca024.jpg
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Appendix
List of figures Bibliography
List of figures II
Satellite Image of the ITC
http://de.wikipedia.org/wiki/Bild:
IntertropicalConvergenceZone-EO.jpg
Inter Tropic Conversion
http://de.wikipedia.org/wiki/Bild:ITC.jpg
Hadley Cell
http://de.wikipedia.org/wiki/Bild:
Tropenklima.jpg
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Appendix
List of figures Bibliography
Bibliography I
G. H. Haug et. al.
Climate and the Collapse of Maya Civilization.
Science, 299:1731–1735, 2003.
D. A. Hodell et. al.
Terminal Classic drought in the northern Maya lowlands
inferred from multiple sediment cores in Lake
Chichancanab (Mexico).
Quanternary Science Reviews, 24:1413–1427, 2005.
D. A. Hodell et. al.
Solar Forcing of Drought Frequency in the Maya Lowlands.
Science, 292:1367–1370, 2001.
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate
Appendix
List of figures Bibliography
Bibliography II
L. C. Peterson and G. H. Haug.
150 Jahre Trockenheit.
Spektrum der Wissenschaft, Januar 2006.
Wikipedia in Spanish
Cultura maya
http://es.wikipedia.org/wiki/Antiguos_mayas
Wikipedia in German
Cultura maya
http://de.wikipedia.org/wiki/Maya
Wikipedia in English
Cultura maya
http:
//en.wikipedia.org/wiki/Maya_civilization
Peter Barmet, Thomas Kuster, André Welti
Maya and Climate