Research Projects
- Tropical Pacific Climate &
Hydrology Since the Last Glacial Maximum
- Tropical Pacific climate changes during the last
2,000 years
- Holocene changes in the Intertropical Convergence
Zone (ITCZ)
- Paleohydrologic reconstructions from
molecular & isotopic changes in tropical Pacific
lake, bog & ocean sediments
- El Niño-Southern Oscillation variations since the
last
glacial maximum
- SST reconstructions from alkenones
in Eastern Equatorial Pacific sediments
- Smittenberg, Saenger, Dawson, Sachs (2011) Compound-specific
D/H ratios of the marine lakes of Palau as proxies for West Pacific
Warm Pool hydrologic variability. Quaternary
Science Reviews Vol. 30: 921-933.
- Sachs & Myhrvold (2011) "A
shifting band of rain." Scientific
American Vol. 304: 60-65.
- Zhang, Metzger, Sachs (2011) "Co-occurrence
of long chain diols, keto-ols, hydroxy acids and keto acids in recent
sediments of Lake El Junco, Galapagos Islands." Organic Geochemistry Vol. 42:
823-837.
- Carré, Azzoug, Bentaleb, Chase, Fontugne, Jackson,
Ledru, Maldonado, Sachs, Schauer (2011) Mid-Holocene
mean climate in the south eastern Pacific and its influence on South
America. Quaternary International
In Press, Corrected Proof.
- Sachs & Ladd (2010) "Climate
and oceanography of the Galapagos in the 21st century: expected changes
and research needs." Galapagos
Research Vol. 67: 50-54.
- Sachs, Sachse, Smittenberg,
Zhang, Battisti, Golubic (2009) "Southward
movement of the Pacific intertropical convergence zone AD 1400-1850."
Nature
Geoscience, 2(7): 519-525.
- Koutavas
& Sachs (2008) Northern
timing of deglaciation in the
eastern equatorial Pacific from alkenone paleothermometry, Paleoceanography
Vol. 23: PA4205, doi:10.1029/2008PA001593.
- Sachse & Sachs (2008) Inverse
relationship between D/H fractionation in cyanobacterial lipids and
salinity in Christmas Island saline ponds. Geochimica et Cosmochimica Acta
Vol.72: 793-806.
- Pahnke,
Sachs, Keigwin, Timmermann, Xie
(2007) Eastern
tropical Pacific
hydrologic changes during the past 27,000 years from D/H ratios in
alkenones, Paleoceanography
Vol. 22, PA4214, doi:10.1029/2007PA001468.
- Smittenberg & Sachs (2007) Purification
of dinosterol for hydrogen isotopic analysis using high-performance
liquid chromatography–mass spectrometry Journal of Chromatography A
Vol. 1169: 70-76.
- Zhang, Metzger & Sachs
(2007) Biomarker
evidence for the co-occurrence of three races (A,
B and L) of Botryococcus braunii in El Junco Lake,
Galápagos, Organic
Geochemistry Vol. 38: 1459-1478.
- Saenger, Smittenberg, Miller, Sachs (2006) A
Physico-chemical survey of inland lakes and saline ponds: Christmas
Island (Kiritimati) and Washington (Teraina) Islands, Republic of
Kiribati Saline
Systems Vol. 2(1): 8
- Sachs
& Smittenberg (2005) Reconstructing the History of El
Niño from Galapagos Lakes EAPSpeaks,
MIT-EAPS Newsletter Vol. 1(1).
- Koutavas, Lynch-Stieglitz,
Marchitto, Sachs (2002) "El
Niño–like pattern in Ice Age tropical
Pacific sea surface temperature." Science
Vol. 297:
226-230.
- Hydrogen isotopes in algal and plant lipids and their
application to paleoclimatology
- Phytoplankton Continuous cultures
We are growing mangroves in our laboratory in order to quantify the
hydrogen and carbon isotope fractionation during lipid synthesis across
a range of salinities. These experiments are being
performed by graduate student Nemiah Ladd with assistance from our
culturing guru Kathleen Hemeon, UW undergraduates Thien-Y Le and Tory
Johnson, and Interlake High School student David Golub.
The figure on the left shows the outside
of 3 of the growing tanks. The plastic tent keeps the humidity high.
There is a mock tidal cycle with two high and two low tides per day.
The figure on the right shows the inside of the 15 PSU salinity tank on
October 3, 2011. The largest plants are Rhizophera apiculata, the propagules of which were collected in Pohnpei, Micronesia in July, 2011. There are also Rhizophera mangle and Laguncularia racemosa plants growing in this tank, from propagules and seeds from Florida. If you look closely you can also see some Xylocarpus granatum
seeds that have roots, but no shoots yet. These were collected in
Kosrae, Micronesia in September, 2011.
 
- Sachs & Schwab (2011) Hydrogen
isotopes in dinosterol from the Chesapeake Bay estuary. Geochimica et Cosmochimica Acta
Vol. 75(2): 444-459.
- Schwab & Sachs (2011) Hydrogen isotopes in
individual alkenones from teh Chesapeake Bay estuary. Geochimica et Cosmochimica Acta.
In press.
- Schwab & Sachs (2009) The
measurement of D/H ratios in alkenones and their isotopic heterogeneity.
Organic
Geochemistry Vol. 40: 111-118.
- Zhang, Z., J.P. Sachs, A. Marchetti
(2009) Hydrogen
isotope fractionation in freshwater and marine algae: II. Temperature
and nitrogen-limited-growth-rate effects. Organic Geochemistry
Vol. 40(3): 428-439.
- Bühring, S.I., R.H. Smittenberg, D. Sachse, J.S.
Lipp, S. Golubic, J.P. Sachs, K.-U. Hinrichs, R.E. Summons (2009) "A
hypersaline microbial mat from the Pacific Atoll Kiritimati: insights
into composition and carbon fixation using biomarker analyses and a
13C-labeling approach." Geobiology
7: 1-16.
- Bowman
& Sachs (2008) Chemical
and physical properties of some saline lakes in Alberta and Saskatchewan,
Saline
Systems. Vol. 4:3.
- Sachse
& Sachs (2008) Inverse
relationship between D/H fractionation in cyanobacterial lipids and
salinity in Christmas Island saline ponds, Geochimica et Cosmochimica Acta
Vol.72: 793-806.
- Zhang & Sachs (2007) Hydrogen
isotope fractionation in freshwater algae: I. Variations
among lipids and species, Organic
Geochemistry
Vol. 38: 582-608.
- Smittenberg & Sachs (2007) Purification
of dinosterol for hydrogen isotopic analysis using high-performance
liquid chromatography-mass spectrometry. Journal of Chromatography A,
1169(1-2), 70-76.
- Englebrecht & Sachs (2005) Determination
of sediment provenance at drift sites using hydrogen isotopes and
unsaturation ratios in alkenones, Geochimica et Cosmochimica Acta
Vol. 69(17): 4253-4265
- Deep ocean oxygen, carbon storage & the
biological pump
- Carré, Azzoug, Bentaleb, Chase, Fontugne, Jackson,
Ledru, Maldonado, Sachs, Schauer (2011) Mid-Holocene
mean climate in the south eastern Pacific and its influence on South
America. Quaternary International
In Press, Corrected Proof.
- Koutavas
& Sachs (2008) Northern
timing of deglaciation in the
eastern equatorial Pacific from alkenone paleothermometry, Paleoceanography
Vol. 23: PA4205, doi:10.1029/2008PA001593.
- Pahnke
& Sachs (2006) "Sea
surface temperatures of southern
middle-latitudes 0-160 ky BP."
Paleoceanography
Vol. 21: PA2003, doi:10.1029/2005PA001191
- Sachs
& Anderson (2003) "Fidelity
of alkenone paleotemperature
reconstructions in southern Cape Basin sediment drifts" Paleoceanography
Vol. 18(4): 1082.
- Stenni
et al. (2003)
"A
late-glacial high resolution site and source temperature record
derived from the EPICA Dome C isotope records (East Antarctica)." Earth and Planetary Science
Letters Vol. 217: 183-195.
- Koutavas, Lynch-Stieglitz,
Marchitto, Sachs (2002) "El
Niño–like pattern in Ice Age tropical
Pacific sea surface temperature." Science
Vol. 297:
226-230.
- Lehman, Sachs, Crotwell, Keigwin, Boyle (2002). "Relation
of subtropical Atlantic temperature, high latitude ice rafting, deep
water formation, and European climate 135,000-60,000 years ago."
Quaternary Science Reviews 21: 1917-1924.
- Sachs,
Anderson & Lehman (2001) "Glacial
surface temperatures of the
southeast Atlantic Ocean." Science
Vol. 293:
2077-2079.
- Sachs & Lehman (1999) "Subtropical
North Atlantic temperatures 60,000 to 30,000 years ago." Science Vol. 286: 756-759.
- Holocene cooling of the Northwest Atlantic Ocean
- The origin of fine particles in sediment
drifts
-
- Eastern Mediterranean sapropels
- Nitrogen & carbon isotopes in chlorophyll
|
People
Julian
Sachs -
Principal Investigator
 Dr. Josh Gregersen - Research Scientist
/ Lab Manager
Kathleen Hemeon - Research Aide I, Phytoplankton Specialist
 Dr. Julie Richey - NOAA Postdoctoral Fellow
 Dan Nelson - Graduate Student
Alyssa Atwood - Graduate Student,
NSF Graduate Fellow, DOE Graduate Fellow
 Nemiah Ladd
- Graduate Student, NSF Graduate Fellow
 Ashley
Maloney - Graduate Student, UW Program on Climate Change Graduate Fellow
 Conor Myhrvold - MIT Science
Writing Graduate Student
 Tory Johnson - UW Undergraduate
 Jake Zaragoza - JISAO Summer Intern /
Gonzaga Univ. Undergraduate
 Johnny Huynh - UW Undergraduate
 Ariel Townsend - UW Undergraduate
Thien-Y, Le - UW Undergraduate
David Golub - Interlake
High School Gifted Student Intern
Lab Alumni
 Dr.
Avery Cook Shinneman - Postdoctoral Investigator
 Dr. Ines
Mügler -
Humboldt Postdoctoral Fellow
 Dr.
Orest Kawka - Lab Manager / Research Scientist II
 Amanda Chomos, Laboratory
Assistant
 Dr. Juzhi Hou - UW PCC
Postdoctoral Fellow
Dr. Matthieu Carre - JISAO Postdoctoral Fellow
 Brittany Demianew - Research Scientist I
 Dr. Valerie Schwab - Swiss NSF Postdoctoral Fellow
 Dr. Dirk
Sachse - Humboldt Postdoctoral Fellow
 Dr.
Rienk Smittenberg - Comer
Postdoctoral Fellow
Dr.
Katharina
Pahnke - Comer Postdoctoral Fellow
Dr.
Zhaohui
Zhang - Comer Postdoctoral Fellow
Casey
Saenger - Graduate Student
Recent
Undergraduate Researchers
 Kyle Thomas - Texas Southern
University Undergraduate, NOAA/JISAO Intern
 Fran Janny - UW Undergraduate
 Jeff Bowman
- Levinson & Mary Gates Scholar
Jane Lee
Eric Battisti
Brittany Demianew
Carie Frantz
Evan Howard
Brittany Kimball
Daniel Luksic
Jen Nomura
Recent High
School Interns
Nathan Kato - Interlake High School Gifted Student Intern
Lab Photos
(We like to snowboard & ski!)
Crystal Mountain - March 29, 2011
Ashley & Julie on SHENDA - Nov 2, 2010
L to R: Julian, Dan, Avery, Julie, Mat, Ashley
 Crystal Mountain - March
15, 2010
L to R: Alyssa, Julian, Dan, Nemiah, Sarah, Jesse
 Crystal Mountain -
April 5, 2009
L to R: Julian, Dan, Mt. Rainier, Alyssa, Orest
 Mt. Baker Powder Day - March 31,
2008
L to R: Alyssa, Julian, Dan
 Mt. Baker Powder
Day - April 11, 2007
L to R: Orest, Rienk, Valerie, Matthieu, Julian, Dirk
 Steven's Pass Powder Day - March 9, 2006
L to R: Luzzi, Valerie, Julian, Dirk, Rienk
|
Chesapeake
Bay: May 2006
Preparing a
Filtration System
Kosrae,
FSM: August
2009
Inside of batch culturing
chamber
Chemostat Culture of 
