Northern Oscillations and the Great Climate Flip-FlopPoorna Pal Poorna Pal MS MBA Ph.D.MS MBA Ph.D.
Professor of GeologyProfessor of GeologyGlendale Community CollegeGlendale Community College
The Great Climate Flip-flop
by
WILLIAM H. CALVIN
When 'climate change' is referred to in the press, it
normally means greenhouse warming, which, it is predicted, will cause
flooding, severe windstorms, and killer heat waves. But warming could also lead,
paradoxically, to abrupt and drastic cooling — a
catastrophe that could threaten the end of
civilization.
Observed Sea Surface Temperatures (°C) 7-day average centered on Jan 10, 2001
Observed Sea Surface Temperature Anomalies (°C)
1981 1982 1983
1 Gulf Stream2 N. Atlantic Drift3 Labrador current4 W. Greenland Drift5 E. Greenland Drift6 Canary current
7 N. Equatorial current8 N. Equatorial CC9 S. Equatorial current10 S. Equatorial CC11 Equatorial CC12 Kuroshio current
13 N. Pacific Drift14 Alaska current15 Oyashio current16 California current17 Peru (Humbolt) current18 Brazil current
19 Falkland current20 Benguela current21 Agulhas current22 West Wind Druft23 W.Australian current24 E. Australian current
2324
Strong Negative PhaseStrong Negative Phase
• reflects subnormal heights and reflects subnormal heights and pressures at high latitudes, ab-pressures at high latitudes, ab-normal heights and pressures normal heights and pressures over central North Atlantic, over central North Atlantic, eastern US and western Europe;eastern US and western Europe;
• tends to be associated withtends to be associated with
ColderColdereastern US, eastern US, western Europewestern Europe
WarmerWarmerGreenland, Greenland, southern Europesouthern Europe
DrierDriernorthern Europe,northern Europe,ScandinaviaScandinavia
WetterWettersouthern and southern and central Europecentral Europe
Strong Positive PhaseStrong Positive Phase
• reflects abnormal heights and reflects abnormal heights and pressures at high latitudes, sub-pressures at high latitudes, sub-normal heights and pressures normal heights and pressures over central North Atlantic, over central North Atlantic, eastern US and western Europe;eastern US and western Europe;
• tends to be associated withtends to be associated with
WarmerWarmereastern US, eastern US, western Europewestern Europe
ColderColderGreenland, Greenland, southern Europesouthern Europe
WetterWetternorthern Europe,northern Europe,ScandinaviaScandinavia
DrierDriersouthern and southern and central Europecentral Europe
-4
-2
0
2
4
Jan-50 Jan-60 Jan-70 Jan-80 Jan-90 Jan-00
No
rth
ern
Osc
illat
ion
Ind
exN
ort
her
n O
scill
atio
n In
dex
Monthly DataMonthly DataAnnually Annually Averaged Averaged DataData
0
2
4
6
0 16 32 48 64
Wave NumberWave Number
Rel
ativ
e E
ner
gy
Rel
ativ
e E
ner
gy
85.3
yea
rs85
.3 y
ears
9.5 years9.5 years
2.7 years2.7 years
2.5 years2.5 years5.7 years5.7 years
-0.2
0.0
0.2
0.4
0.6
0.8
1.0
50 100 150 200
Lag (Months)Lag (Months)
Au
toco
rrel
atio
nA
uto
corr
elat
ion
96 months96 months
The Spectral (below) and The Spectral (below) and Correlogram (alongside) Correlogram (alongside) Analyses of Monthly NOI Analyses of Monthly NOI Data since 1950Data since 1950
The Global Conveyor Belt
Broecker, W.S. "The great ocean conveyor," Oceanography,4:79-89 (1991).
Atlantic meridional section at 25°W: TemperatureAtlantic meridional section at 25°W: Temperature
Atlantic meridional section at 25°W: SalinityAtlantic meridional section at 25°W: Salinity
Atlantic meridional section at 25°W: DensityAtlantic meridional section at 25°W: Density
Stream functions of meridional ocean transport in the Atlantic for the present climate (left).
Stream functions of meridional ocean transport in the Atlantic for the last glacial maximum (right),
13.5
14.0
14.5
15.0
1880 1920 1960 2000 A.D.
Mea
n A
nn
ual
Tem
per
atu
re (
°C)
Northern Hemisphere
SouthernHemisphere
Global
1951-1980 average
Global mean temperature since 1866Global mean temperature since 1866
0
0.05
0.10
0.15
0.20
0.25
-0.04 -0.02
Annual Temperature Change (°C)Annual Temperature Change (°C)
0 0.02 0.04
Fre
qu
ency
Fre
qu
ency
1867-2000 AD1867-2000 ADGlobal Mean DataGlobal Mean Data
x = 0.000132x = 0.000132s = 0.011238s = 0.011238
-2
-1
0
1
2
1,000 1,200 1,400 1,600 1,800 2,000 AD
Southern HemisphereSouthern Hemisphere
Northern HemisphereNorthern Hemisphere
Jones, P.D., Briffa, K.R., Barnett, T.P. and Tett, S.F.B.High-resolution palaeoclimatic records for the last millennium: interpretation, integration and comparison with General Circulation Model control-run temperaturesTHE HOLOCENE, 8: 455-471 (1998)
δT
(° C)
δT
(° C)
Through most of the last millennium, though, Southern Through most of the last millennium, though, Southern Hemisphere has been generally warmer than the Northern Hemisphere has been generally warmer than the Northern HemisphereHemisphere
0.00
0.04
0.08
0.12
-0.08 -0.04 0 0.04 0.08
Annual ChangeAnnual Change
Fre
qu
ency
Fre
qu
ency
Mean Annual ChangeMean Annual ChangeStandard DeviationStandard Deviation
== 1.481.481010-5-5
== 0.01870.0187
5% Probability that annual change 5% Probability that annual change will be < -0.037 or >0.037will be < -0.037 or >0.037
Annual temperature changes in the Annual temperature changes in the past millenniumpast millennium
0.0001
0.001
0.01
0.1
1
-5 -4 -3 -2 -1 0 1 2 3 4 5
Z-ScaleZ-Scale
Cu
mu
lati
ve F
req
uen
cyC
um
ula
tive
Fre
qu
ency
Observed Observed DataData
The The Normal CurveNormal Curve
The tail probabilities exceed those predicted by the Normal distribution
model
The past millenniumThe past millennium
-8
-4
0
4
050,000100,000150,000200,000250,000
δδ1
81
8OO
Years BPYears BP
GRIPGRIP
-8
-6
-4
-2
0
2
δT
(°C)
δT
(°C)
VostokVostok
-10
-5
0
5
20,00030,00040,00050,000 δδ1
81
8OO
GRIP: GRIP: Blunier et al. NATURE, 394: 739-743 (1998)Blunier et al. NATURE, 394: 739-743 (1998)
Younger Dryas
J. Jouzel, C. Lorius, J.R. Petit, N.I. Barkov & V.M. Kotlyakov (1994): “Vostok isotopic temperature record” in TRENDS: A COMPEDIUM OF DATA ON GLOBAL CHANGE [ORNL/CDIAC-65. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, Oak Ridge, Tenn., U.S.A.]
S.J. Johnson, D. Dahl-Jensen, W. Dansgaard & N.S. Gundestrup (1995): “Greenland palaeotemperatures derived from GRIP borehole temperature and ice core isotope profiles”
TELLUS, 47B: 624-629.
0.0
0.1
0.2
-0.06 -0.03 -0.01 0.01 0.03 0.06
Annualized temperature changes as Annualized temperature changes as seen in the 10-50 Ka BP GRIP seen in the 10-50 Ka BP GRIP record record
Annualized ChangeAnnualized Change
Fre
qu
ency
Fre
qu
ency
Mean Annualized Mean Annualized ChangeChange
Standard DeviationStandard Deviation== -4.30-4.301010-5-5
== 0.01020.0102
5% Probability that annual 5% Probability that annual change will be < -0.02 or change will be < -0.02 or
>0.02>0.02
0.0001
0.001
0.01
0.1
1
-5 -4 -3 -2 -1 0 1 2 3 4 5
Z-ScaleZ-Scale
Cu
mu
lati
ve F
req
uen
cyC
um
ula
tive
Fre
qu
ency
The The Normal CurveNormal Curve
Observed Observed DataData
The tail probabilities exceed those predicted by the Normal distribution
model
10-50 Ka BP 10-50 Ka BP GRIP DataGRIP Data
The past millennium has The past millennium has been about as stable, been about as stable, temperature-wise, as the past temperature-wise, as the past 10-50 Ka BP interval that 10-50 Ka BP interval that included the Younger Dryas included the Younger Dryas Ice Age. Ice Age.
Thank You!