dynamics of the sea surface temperature on a global scale using satellite measurements g. vysotskaya...
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Dynamics of the sea surface temperature on a global scale using satellite measurements
G. Vysotskaya (1,2), A. Shevyrnogov (1,3) (1) Institute of Biophysics of SB RAS, Krasnoyarsk, Russia,
(2) Institute of Computational Modelling of SB RAS, Krasnoyarsk, Russia
(3) Siberian Federal University, Krasnoyarsk, Russia
108 satellite MODIS images (2160 x 4320) – 7.2002-7.2011 and 300 AVHRR images (4096 x 8192) - 1985 - 2009 were used in this investigation. Sea surface temperature may be represented as a sum: Ci,j(t) = Fi,j( (t)) +ξi,j( (t))+Ui,j (t),where Fi,j(m) is a mean for (i,j); (t) is a number of a month for time t; ξi,j(m) is a random variable, that describe natural variability of the ocean. It depends on (i,j) and a month. Ui,j(t) is a some additional variable, that can be defined by climatic changes, human impact etc.
Norm data
)(,,
)(,,)(,ji,ji,
)()(
tji
tjit
D
EtCtA
Ei,j,m is a mean value for a point (i,j) and a month m
Di,j,m is a variance for a point (i,j) and a month m.
Define positive anomaly values as the upper 20% (p0.8)and negative anomaly as the lower 20% (p0.2)
0
5
10
15
20
25
30
35
40
45
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
Time
Pro
po
rtio
n o
f th
e t
ota
l are
a (
%)
0-20% 80-100%
Square of negative and positive anomalies by AVHRR data (60°N- 60°S)
Square of negative and positive anomalies by MODIS data (60°N- 60°S)
0
5
10
15
20
25
30
35
40
45
2002
.5
2003
.0
2003
.5
2004
.0
2004
.5
2005
.0
2005
.5
2006
.0
2006
.5
2007
.0
2007
.5
2008
.0
2008
.5
2009
.0
2009
.5
2010
.0
2010
.5
2011
.0
Time
Pro
po
rtio
n o
f th
e t
ota
l are
a (
%)
0-20% 80-100%
Positive anomalies (80-100%)
0
10
20
30
40
50
60
70
8019
85
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
Par
t o
f th
e to
tal s
qu
are
(%)
Pacific ocean Atlantic ocean Indian ocean
Square of positive anomalies by AVHRR data (30°N- 30°S)
Negative anomalies (0-20%)
0
10
20
30
40
50
60
70
80
Pa
rt o
f th
e t
ota
l s
qu
are
(%
)
Pacific ocean Atlantic ocean Indian ocean
Square of negative anomalies by AVHRR data (30°N- 30°S)
The sum of temperature anomalies
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
deg
rees
Pacific ocean Atlantic ocean Indian ocean
The Pacific ocean
0
10
20
30
40
50
60
70
8019
85
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
Par
t o
f th
e to
tal s
qu
are
(%)
Negaitive anomalies (0-20%) Positive anomalies (80-100%)
Square of negative and positive anomalies by AVHRR data (30°N- 30°S)
The Atlantic ocean
0
10
20
30
40
50
60
70
8019
85
1986
1988
1989
1990
1992
1993
1994
1996
1997
1998
2000
2001
2002
2004
2005
2006
2008
2009
Par
t o
f th
e to
tal s
qu
are
(%)
Negaitive anomalies (0-20%) Positive anomalies (80-100%)
The Indian ocean
0
10
20
30
40
50
60
70
8019
85
1986
1988
1989
1990
1992
1993
1994
1996
1997
1998
2000
2001
2002
2004
2005
2006
2008
2009
Par
t o
f th
e to
tal s
qu
are
(%)
Negaitive anomalies (0-20%) Positive anomalies (80-100%)
Conclusions• Long-term changes of sea surface temperature
are global.• The largest positive anomalies appear almost
synchronously in the different oceans.
• The largest negative anomalies usually are not synchronous in the different oceans
• Variability of SST in the Atlantic and Indian oceans is higher than in the Pacific ocean.