EARTH OBSERVATION AND
GLOBAL CHANGE
SATELLITE OCEANS
OBSERVATION IN RELATION
TO GLOBAL CHANGE.
MANUEL CANTÓN-GARBÍN
2007
UNIVERSIDAD DE ALMERÍA
SPAIN
INDEX:
1. SOME FACTS ABOUT THE CLIMATE.
2. THE OCEANS.
3. OCEANS SATELLITE OBSERVATIONS.
4. MODELS AND PREDICTIONS ABOUT CLIMATE.
1.
SOME FACTS ABOUT
CLIMATE.
a) CLIMATE VARIABILITY: Short
term (days to months).
b) CLIMÁTIC CHANGE : Long term
(years).
2. THE CLIMATE HAS ALWAYS BEEN
CHANGING.
3. CLIMATE Influences: (Many coupled
processes: Solar Activity ; Orbital Earth
parameters; Atmosphere - Ocean
interaction; Plate tectonics,…).
4.
The climate is a nonlinear phenomenon,
strongly joined and chaotic. This means
that the climate as a whole can be
unpredictable. (Burroughs, 2003; Climate
Change, Cambridge).
Earth's climate is anything but stable, with dramatic swings in
cooling and warming over the past 1 million years and past
140.000 years (next slide). During the las interglacial
(120.000 years ago) the sea level was 6 to 7 m higher than it
is today. (www.WHOI.edu/ Graphics, Jack Cook, 2006).
www.WHOI.
edu/
GraphicsJack
Cook
Houghton,
2004
Cambridge
Univ. Press
IPCC 2001
Upper 300m
Upper 3000m
Ocean warming from 1950 to 1990. (Levitus: Science, 2000)
Milankovitch
Theory:
Expalin the 60% of ice
variation in the Earth:
3 orbital variations:
1. Excentricity change
every 100 ka.
2. Earth axis angle:
change between 21.6º
and 24.5 every 41Ka.
3. Perihelium: change
every 23 Ka.
(Rutherford, S. 1997)
Relation CO2 and Temp. (From Houghton 2004).
Heat transport by the Ocean
HN
Atlantic Ocean
HS
North. Hemisph.: Atlant Oc >> Pacif Oc; SH: Pacif Oc =2 Indian Oc.
(Houghton et al. 1996).
Fig. 2b. Global surface circulation (The Open University 1989).
Fig. 4. Gulf stream current.
Calvin, 1998.
Fig. 5. During this circulation of cold and warm water, carbon dioxide is also
transported. Cold water absorbs carbon dioxide from the atmosphere, and some sinks
deep into the ocean. When deep water comes to the surface in the tropics, it is warmed,
and the carbon dioxide is released back to the atmosphere (IPCC 2001).
The stop of CTH.
Rahmstorf,
Nature, 2002
Change in annual temperature 30 years after a
collapse of the thermohaline circulation.
Rahmstorff, NATURE 2002.
Productivity
after the end
of CTH.
Takes about
1300 years
to recover.
Schmittner,
Nature
2005
Hadley Centre models suggest a reduction in the strength of the Gulf Stream
by as much as a quarter, but not a collapse. However, even with this
reduction in the Gulf Stream, the net result of climate change will be a warmer
Europe.
(HADLEY CENTER, UK, 2006).
3. OCEAN SATELLITE
OBSERVATIONS
Advantages: Global observation ,
repetitive, isolated areas, different
spectral bands (IR,VIS, microwaves).
Disadvantages: SST ; only from 1979.
PARAMETERS
MEASURED
Parameters
measured
fromFROM
space.SPACE.
* SST.
* Cla.
* Salinity.
* Roughnes.
* Altitude.
ENVISAT
ESA
ENVISAT
400
Tb/year
>1Tb/day
VISIBLE
Color
Cla, Productivity, Fisheries.
High levels of Cla concentration (yellow) near the coast in Sahara upwelling.
A big cyclonic eddy at the S of Gran Canaria (dark in the center and yellow at the borders.
Sahara upwelling close to the shore. A local upwelling can be seen to the west
of Fuerteventura island.
Cla south of Canary islands and at Sahara upwelling from
SeaWiFS. Some gyres at the west of La Palma
and west and south of Gran Canaria (Borges, R. et al. 2004).
Global NDVI and Cla for September 2000 from SeaWiFS
SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE).
Primary production
distribution for the
SeaWiFS (1997-mid
2002) and the CZCS
(1979-mid 1986).
Gregg, W.
Geop.Res 2003.
About 6% less
ocean Cla from
1980 until present.
Gregg, W.
Geop.Res 2003.
INFRARED
Sea Surface Temperature
(SST).
Fig. 7. ATSR nighttime thermal IR
image showing a
giant anticyclonic
eddy south of Gran
Canaria (CCLRC,
UK).
Fig. 8 a) SST and b) Cla from Aqua MODIS
(From NASA).
AVHRR SST map for
8 June 1987. Ocean
features
like the cold Sahara
upwelling,
cold eddy South of
Gran Canaria (GC)
and warm wakes at
the south of
La Palma, Gomera
and GC are clearly
visibles.
SST and CLa maps showing a cyclonic, cold eddy, at the south of the channel between
Tenerife and Gran Canaria (www.ulpgc.es/orpamcanarias/).
MODIS Average SST for MAY 2001. From NASA.
AQUA (AMSR-E). JUNE 2002-SEPT 2003.
Fig. 9. SST from AQUA-AMSR-E for the 1 of June 2003 (From NASA).
SALINITY
ESA-SMOS 2007
NASA-AQUARIUS 2009
Fig. 10. Simulated seasonal (winter) sea-surface salinity map
(ESA).
Simulated seasonal
sea-surface salinity
maps. They exhibit only
small variations, but
demonstrate the
uniform pattern of a
saltier Atlantic
compared to the
Pacific. Since in-situ
sampling is difficult,
currently the only way
of estimating global
ocean salinity is to
simulate the data using
complex computer
models (From ESA).
Geometry of ERS SAR
ESA
Internal waves at the strait of Gibraltar.
VISIBLE
Space shuttle
ERS – SAR
7-I-1992
Oil slicks NE of the image and surface ocean
roughness (light) near the shore at the border
between France and Italy. Bright spots near
the coast are due to the local wind (Mistral)
blowing from the valleys. (ERS-1, ESA).
Waves from SEASAT 1978.
The Open Univ. 1987
Eddy formation and decay at the North of Bermuda island due to the friction between
the Gulf Stream and the shore.
Oil slick at the sea surface (black). Two ships (white spots) moving north and south and
their wakes are also visibles at the right and left of the image.
Ship route of the
Prestige tanker in
November 2002.
Fig. 11. ASAR ENVISAT 17-NOV-2002. ESA.
Envisat's ASAR image acquired 17
November 2002 shows a double-headed
oil spill originating from the stricken
Prestige tanker, lying 100 km off the
Spanish coast.
PRESTIGE
SCATTEROMETER
Ocean surface wind vector.
Fig. 12. Global
winds for the
8/I/2004
computer from
NSCATT (From
NASA).
NASA
ALTIMETER
Ocean surface topography.
Intensity of winds.
Significant wave height.
Fig. 14.
Dynamic
topography
(Ocean Surface
Topography)
measured by
the altimeter
(From NASA).
The TOPEX/POSEIDON at an altitude of
1300km (1992).
JASON: 12/07/2001
AVHRR SST for 30-July 1992.
(From Tejera et al. 2002).
Fig. 15 a): Eddy Kinetic Energy (EKE)
ERS-1 SUMMER 1992.
Fig. 15b). EK T/P
SUMMER 1993
AVHRR SST 10-8-1993.
Upwelling, filament, warm wakes,
cold and warm eddies south of GC
(From Tejera et al. 2002).
Fig. 16. Equivalent slope variability .... from 5 years of T/P data
(IFM. 2006).
Fig. 17. Rate of mean sea level change from 1993 to 1998
Cabanes et al. 2001.
SEA LEVEL RISE and its components
From Tsimplis, M. National Oceanography Centre,
Southampton, UK.
Antarctica not included
Total
Thermal expansion
Glaciers
Greenland
0.6
0.4
HadCM2 GHG1
0.2
0.0
Year 1900
1950
2000
2050
2100
EL NIÑO
Fig. 18. Conditions in the Pacific during: a) normal and b) El Niño conditions.
ST
http://www.enso.info/
www.cnes.fr/web/
Before (January 1998) of El Nino. (SeaWiFS) NASA)
www.cnes.fr/web/
During (Feb. 1999) of La Niña-related Pacific Phytoplankton Bloom. (SeaWiFS- NASA)
The height is the sea level anomaly (-40 to +40 cm) measured by the Radar
Altimeter and the colour is the sea surface temperature anomaly (-6 to +8
degrees) measured by the Along Track Scanning Radiometer (ATSR). Both of
these instruments are also on-board Envisat (From ESA).
Fig. 19. Sea level and temperature anomalies during El Niño 1997 (From ESA).
Sea level and temperature anomalies during July 1998 (From ESA).
Sea level and temperature anomalies during La Niña, January 2001 (From ESA).
El Niño and its global effects (from NOAA).
El Niño and its global effects (from NOAA).
(NOAA/CIRES Climate Diagnostics Center).
4. MODELING CLIMATE CHANGE.
Needs to model:
1. Atm-ocean Interacción (ENSO, NAO, AO).
2. OceAnic Currents.
3. Volcanos.
4. Solar activity.
5. Orbital parameters.
6. Changes in the athmospheric composition.
7. Plate tectonics.
8. Human activities.
ANNUAL TEMPERATURE CHANGES FOR 2050
(Hadley Centre, UK)
ANNUAL PRECIPITATION CHANGES FOR 2050
Hadley Centre, UK
CONCLUSIONS
As we have seen, sensors installed onboard satellites provide us with a
large and different type of data for global observations. They are
contributing for the last thirty years to the understanding of some complex
phenomena that control our climate such as oceanic currents, coupled
atmospheric-ocean phenomena, changes in oceans productivity and more.
The use of satellite data together with the last generations of climate
numerical models can be one of the most important keys to look in our
future.
But we haven not many time to act if we wish to survive in this planet.