titolar  
     
     
  WHAT HAPPENS WITH CLIMATE CHANGE?
 
  PROJECT DESCRIPTION
 
  SCIENTIFIC RESULTS
 
  THE PROJECT
PARTNERS
- Environmental Organic Geochemistry
- Atmospheric Aerosols
- Limnogeology and Global Change
- Ecology and Environmental Change
- Marine Geosciences
- Coastal and Ocean Engineering
- Ocean Geosciences
- Atmospheric Contamination and Meteorology
- Ecology of Perturbations and Forestal Restoration
- Effects of Pollution on Plants and Carbon Cycle
- Physical Institute
 
  FOR PROJECT PARTICIPANTS
 
  ADMINISTRATIVE
MATTERS
   

 
  THE PROJECT PARTICIPANTS
Environmental Organic Geochemistry
Institute of Environmental Assessment and Water Research
Spanish Council for Scientific Research

Expertise: Analytical chemistry and organic geochemistry

 
 

This group is devoted to the analysis of lipids in environmental samples to obtain information on the climate changes that ocurred in the past. Marine sediment cores have been the main target of the group allowing the reconstruction of the climate changes over the last 450 000 years. The analytical techniques available in the group are as follows

- Systems of gas chromatography with: thermal conductivity, electron capture, nitrogen-phosphorous, flame photometry.
- Systems of gas chromatography coupled to mass spectrometry with electron impact
- Systems of gas chromatography coupled to chemical ionizationmass spectrometry (registry of positive and negative ions)
- System of gas chromatography coupled to mass spectrometry of high resolution electron impact with pyrolysis interface for the measurement of stable isotopes: δD, δ18O, δ15N y δ13C.
- Systems of gas chromatography with flame ionization and electron capture detectors connected to an automatic thermal desorption instrument.
- System of liquid chromatography with diode array detector connected to a mass spectrometer.
- Systems of liquid chromatography coupled to mass spectrometry with interfaces of thermospray, electrospray and atmospheric pressure chemical ionization.

With these techniques the group has made significant contributions to the use of C37 alkenones for surface temperature measurements. It pioneered the use of these compounds for marine paleoproductivity studies, it has also developed the use of n-alkanes and n-alkan-1-ols as markers of wind intensities and as markers of intensities of bottom water currents (n-hexacosan-1-ol index).

The group has participated and is participating in diverse research projects funded by the European Union devoted to understand the climate evolution of the Earth and their impact on the ecosystems:

- EPOCH: Global Changes over the last 30,000 years. January 1991-December 1993.
- Ocean circulation and global climatic changes over the last three interglacials. A contribution to the coordinated program: the study of the last two glacial cycles with particular emphasis on the initiation of the glaciations EV5V-CT92-0117. January 1993-December 1994.
- Surface ocean paleocirculation recorers. Past natural climate variability in high and middle latitude oceans CHRX-CT94-0424. November 1993-March 1997.
- Variability of the glacial and interglacial climates and abrupt climatic changes. Noviembre 1994-Octubre 1997. January 1996-December 1997.
- Reconstruction of paleo-sea water pCO2 using carbon isotope composition of specific biomarkers of autotrophic phytoplankton: sources and sinks of CO2 ENV4-CT96-5021. September 1996-August 1997.
- TEMPUS: Sea-surface temperature evoluton mapping project based on Uk37 stratigraphy ENV4-CT97-0564. 1998-2000.
- Climate variability: How unusual is the holocene? ENV4-CT97-0162. February 1998-January 2001
- POP: Pole-Ocean-Pole: Global stratigraphy for millennial climate variability EVK2-CT-2000-00089. December 2000- November 2004.
- CESOP: Coordinated European Surface Ocean Palaeo-Estimation Collaboration EVR1-CT2001-40018. November 2001-October 2004.
- PROMESS1: PROfiles across Mediterranean sedimentary systems EVR1-CT2001-00041. December 2002-November 2005.
- PACLIVA: Pattern of climate variability in the North Atlantic EVK2-CT2002-00143. December 2002-November 2005.
- EUROLIMPACS: Integrated project to evaluate the impacts of global change on European freshwater ecosystems GOCE-CT-2003-505540. February 2004-January 2009.
-

HERMES: Hotspot Ecosystem Research on the Margins of European Seas. GOCE-CT-2005-511234. April 2005-March 2009.

EXAMPLES OF THE PALEOCEANOGRAPHY BIOMARKER PROXIES THAT PROVIDE INFORMATION ON ABRUPT CLIMANTE CHANGES
move the mouse on the figure for explanation

SEA SURFACE TEMPERATURE
 
 

MARINE PRODUCTIVITY

WIND INTENSITY

INTENSITIES OF DEEP WATER CURRENTS
 
 

Selected references:

B. Martrat, J.O. Grimalt, N.J. Shackleton, L. de Abreu, M.A. Hutterli and T.F. Stocker. Four climate cycles of recurring deep and surface water destabilizations on the Iberian Margin. Science 317, 502-507 (2007).
López-Martínez, C., J.O. Grimalt, B. Hoogakker, J. Gruetzner, M.J. Vautravers, and I.N. McCave. Abrupt wind regime changes in the North Atlantic Ocean during the past 30,000-60,000 years. Paleoceanography 21, PA4215, doi:10.1029/2006PA001275 (2006).
B. Martrat, J.O. Grimalt, C. Lopez-Martinez, I. Cacho, F.J. Sierro, J.A. Flores, R. Zahn, M. Canals, J.H. Curtis and D.A. Hodell- Abrupt Temperature Changes in the Western Mediterranean over the Past 250,000 Years. Science 306, 1762-1765 (2004).
I. Cacho, J.O. Grimalt, M. Canals, L. Sbaffi, N.J. Shackleton, J. Schönfeld and R. Zahn- Variability of the western Mediterranean Sea surface temperature during the last 25,000 years and its connection with the Northern. Hemisphere climatic changes. Paleoceanography 16, 40-52 (2001).
J. Villanueva, E. Calvo, C. Pelejero, J.O. Grimalt, A. Boelaert and L. Labeyrie. A latitudinal productivity band in the central North Atlantic over the last 270 kyr: An alkenone perspective. Paleoceanography 16, 617-626 (2001).
I. Cacho, J.O. Grimalt, F.J. Sierro, N. Shackleton and M. Canals. Evidence for enhanced Mediterranean thermohaline circulation during rapid climatic coolings. Earth and Planetary Science Letters 183, 417-429 (2000).
I. Cacho, J.O. Grimalt, C. Pelejero, M. Canals, F.J. Sierro, J.A. Flores and N. Shackleton- Dansgaard-Oeschger and Heinrich event imprints in Alboran Sea paleotemperatures- Paleoceanography 14, 698-705 (1999).


 
     
   
   
Figure 1. Comparison between the sea surface temperature record obtained with the alkenones in marine sediments from the Alboran Sea (MD95-2034) (Cacho et al., 1999) and the δ18O record in Greenland ice (GISP2 ‰). Observe the good parallelism in the abrupt changes.

Figure 2. Profiles of sea surface temperatures measured from the composition of alkenones in two nearby sites in the Alboran Sea (ODP977) and the Iberian Margin (eastern Atlantic Ocean; MD012443) (Martrat et al 2004 and 2007). Observe the good agreement between the two records, particularly for what concerns abrupt transitions, despite their location in different marine environments (Fig. 2).

Figure 3. Sites in the Alboran Sea (ODP977) and the Iberian Margin (eastern Atlantic Ocean; MD012443) sampled for high resolutions studies over the last 250,000 years.

Figure 4. Description of the precessional modulation of marine productivity using the alkenone concentrations (Villanueva et al., 2001)

Figure 5. Atmospheric δ18O in GRIP. Heinrich events are indicated on top (H); isotopically defined Greenland interstadials (GIS) are also indicated. Sea surface temperature was measured with the unsaturated alkenone ratio. Concentrations of C23-C33 n-alkanes and C20-C30 n-alkan-1-ols, they record wind driven higher plant continental inputs to ODP-1060. Fluxes of C23-C33 n-alkanes and C20-C30 n-alkan-1-ols in ODP-1060. Polar Circulation Index (PCI) in GISP2 and Ca2+ in GRIP. Shaded areas indicate cold events (Heinrich events and Greenland stadials). (Lopez-Martinez et al., 2006)

Figure 6. Record of the n-hexacosan-1-ol index (ratio between n-hexacosan-1-ol and n-nonadecane) in the Alboran Sea (core MD95-2043) that is tracing the degree of oxygen supply to the sedimentary organic matter and the intensity of deep water currents as consequence of turnover (Cacho et al., 2001). This record is compared with the δ18O and δ13C composition in Cibicidoides. The n-hexacosan-1-ol deep water record is showing abrupt increases in formation of Mediterranean deep water in the stadials (cold episodes) of Marine Isotope Stage 3.

Figure 7. Record of the n-hexacosan-1-ol index in the Iberian Margin (core MD01-2443) that is tracing the degree of oxygen supply to the sedimentary organic matter and the intensity of deep water currents as consequence of turnover (Cacho et al., 2001). This record is compared with the δ18O and δ13C composition in Cibicidoides. The n-hexacosan-1-ol deep water record is showing abrupt increases in formation of North Atlantic Deep Water or Antarctic Bottom Water. These can be identified by the increasing or decreasing values of δ13C in benthic foraminifera (Martrat et al., 2007)