CAPTURING CLIMATE VARIABILITY IN STABLE ISOTOPIC PROXIES FROM THE EASTERN EQUATORIAL PACIFIC: WHAT CAN AND CAN’T STABLE ISOTOPES RECORD?

2016 ◽  
Author(s):  
Nicholas J. Martin ◽  
◽  
Jessica L. Conroy ◽  
David C. Noone ◽  
Kim M. Cobb ◽  
...  
Keyword(s):  
Stable Isotopes ◽  
Climate Variability ◽  
Equatorial Pacific ◽  
Eastern Equatorial Pacific ◽  
Stable Isotopic ◽  
Isotopic Proxies

scholarly journals A revised mid-Pliocene composite section centered on the M2 glacial event for ODP Site 846

2021 ◽  
Vol 17 (3) ◽  
pp. 1385-1394
Author(s):  
Timothy D. Herbert ◽  
Rocio Caballero-Gill ◽  
Joseph B. Novak
Keyword(s):  
Time Series ◽  
Stable Isotopes ◽  
Gamma Ray ◽  
Equatorial Pacific ◽  
Sea Surface ◽  
Published Data ◽  
Data Sets ◽  
Stable Isotopic ◽  
Composite Section ◽  
Gamma Ray Attenuation

Abstract. The composite section from ODP Site 846 has provided key data sets for Pliocene stable isotope and paleoclimatic time series. We document here apparent outliers in previously published data sets for stable isotopes and alkenone-derived sea surface temperature (SST) estimates in the Pliocene interval containing the M2 glaciation (ca. 3.290–3.3 Ma) by tying high-resolution core measurements to a continuous downhole conductivity log. We generate a revised sequence of new stable isotopic and alkenone measurements across the M2 event that correlate well to the revised splices of color reflectance and gamma ray attenuation porosity evaluator data from Site 846, and to a new composite section produced at equatorial Pacific ODP Site 850. A new composite splice for Site 846 is proposed, along with composite isotope and alkenone time series that should be integrated into revised Pliocene paleoclimatic stacks.

Enhanced E. huxleyi carbonate counterpump as a positive feedback to increase deglacial pCO2sw in the Eastern Equatorial Pacific

2021 ◽  
Vol 260 ◽  
pp. 106921
Author(s):  
Chiara Balestrieri ◽  
Patrizia Ziveri ◽  
Michaël Grelaud ◽  
P. Graham Mortyn ◽  
Claudia Agnini
Keyword(s):  
Positive Feedback ◽  
Equatorial Pacific ◽  
Eastern Equatorial Pacific

Ocean Response to Wind Variations, Warm Water Volume, and Simple Models of ENSO in the Low-Frequency Approximation

2010 ◽  
Vol 23 (14) ◽  
pp. 3855-3873 ◽  
Author(s):  
Alexey V. Fedorov
Keyword(s):  
Low Frequency ◽  
Equatorial Pacific ◽  
Warm Water ◽  
Water Volume ◽  
Thermocline Depth ◽  
Phase Lag ◽  
Eastern Equatorial Pacific ◽  
The Pacific ◽  
Warm Water Volume ◽  
Frequency Approximation

Abstract Physical processes that control ENSO are relatively fast. For instance, it takes only several months for a Kelvin wave to cross the Pacific basin (Tk ≈ 2 months), while Rossby waves travel the same distance in about half a year. Compared to such short time scales, the typical periodicity of El Niño is much longer (T ≈ 2–7 yr). Thus, ENSO is fundamentally a low-frequency phenomenon in the context of these faster processes. Here, the author takes advantage of this fact and uses the smallness of the ratio ɛk = Tk/T to expand solutions of the ocean shallow-water equations into power series (the actual parameter of expansion also includes the oceanic damping rate). Using such an expansion, referred to here as the low-frequency approximation, the author relates thermocline depth anomalies to temperature variations in the eastern equatorial Pacific via an explicit integral operator. This allows a simplified formulation of ENSO dynamics based on an integro-differential equation. Within this formulation, the author shows how the interplay between wind stress curl and oceanic damping rates affects 1) the amplitude and periodicity of El Niño and 2) the phase lag between variations in the equatorial warm water volume and SST in the eastern Pacific. A simple analytical expression is derived for the phase lag. Further, applying the low-frequency approximation to the observed variations in SST, the author computes thermocline depth anomalies in the western and eastern equatorial Pacific to show a good agreement with the observed variations in warm water volume. Ultimately, this approach provides a rigorous framework for deriving other simple models of ENSO (the delayed and recharge oscillators), highlights the limitations of such models, and can be easily used for decadal climate variability in the Pacific.

scholarly journals Dynamic Metasomatism: Stable Isotopes, Fluid Evolution, and Deformation of Albitite and Scapolite Metagabbro (Bamble Lithotectonic Domain, South Norway)

Geofluids ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-22 ◽  
Author(s):  
Ane K. Engvik ◽  
Heinrich Taubald ◽  
Arne Solli ◽  
Tor Grenne ◽  
Håkon Austrheim
Keyword(s):  
Stable Isotopes ◽  
Chemical Evolution ◽  
Metal Transport ◽  
Ductile Deformation ◽  
Crustal Evolution ◽  
Fluid Type ◽  
Isotopic Data ◽  
Magmatic Rocks ◽  
Stable Isotopic ◽  
Magmatic Fluids

New stable isotopic data from mineral separates of albite, scapolite, amphibole, quartz, and calcite of metasomatic rocks (Bamble lithotectonic domain) give increased knowledge on fluid type, source, and evolution during metamorphism. Albite from a variety of albitites givesδ18OSMOWvalues of 5.1–11.1‰, while quartz from clinopyroxene-bearing albitite gives 11.5–11.6‰.δ18OSMOWvalues for calcite samples varies between 3.4 and 12.4‰and shows more consistentδ13C values of −4.6 to-6.0‰. Amphibole from scapolite metagabbro yields aδ18OSMOWvalue of 4.3 to 6.7‰andδDSMOWvalue of −84 to −50‰, while the scapolite givesδ18OSMOWvalues in the range of 7.4 to10.6‰. These results support the interpretation that the original magmatic rocks were metasomatised by seawater solutions with a possible involvement from magmatic fluids. Scapolitisation and albitisation led to contrasting chemical evolution with respect to elements like P, Ti, V, Fe, and halogens. The halogens deposited as Cl-scapolite were dissolved by albitisation fluid and reused as a ligand for metal transport. Many of the metal deposits in the Bamble lithotectonic domain, including Fe-ores, rutile, and apatite deposits formed during metasomatism. Brittle to ductile deformation concurrent with metasomatic infiltration illustrates the dynamics and importance of metasomatic processes during crustal evolution.

Stable Isotopes Analysis of Precipitation in Subtropical Plateau of Yunnan

2014 ◽  
Vol 1010-1012 ◽  
pp. 1059-1063
Author(s):  
Wei Guan ◽  
Tao Fan ◽  
Xiu Qin Zhu
Keyword(s):  
Stable Isotopes ◽  
Rainy Season ◽  
Mean Value ◽  
Dry Season ◽  
Precipitation Line ◽  
Stable Isotopic ◽  
Different Seasons ◽  
Geographical Position ◽  
The Mean ◽  
The Relationship

To elucidate the relationship between stable isotopes of precipitation (SIP) and the extreme drought in Kunming area, based on the stable isotopes data of the GNIP in Kunming site from 1986 to 2003, the precipitation line equation is brought forward and the seasonal change rule of stable isotopes are discussed. The stable isotopic compositions of precipitation exhibit great diversities in different seasons during to influences of multiple factors, such as monsoon, rainfall amount moisture source and others. The δ18O values in rainwater exhibit significant seasonal variations, the average of-10.12‰ in rainy season, the dry season is-4.5‰, having lower values in the rainy season and higher one in the dry season. The amount effect of precipitation is very distinct, that concealed the temperature effect. Got the special geographical position,dvalues present unique characteristics, the average ofdvalues is 10.78‰ in rainy season, and is 4.86‰ in dry season, the mean value is generally lower than most parts of the world.

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