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.

scholarly journals A Revised Mid-Pliocene Composite Section for ODP Site 846

2020 ◽  
Author(s):  
Timothy D. Herbert ◽  
Rocio Caballero-Gill ◽  
Joseph B. Novak
Keyword(s):  
Time Series ◽  
Stable Isotopes ◽  
Gamma Ray ◽  
Sea Surface ◽  
Primary Data ◽  
Data Sets ◽  
Late Pliocene ◽  
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 errors in primary data sets for stable isotopes and alkenone-derived sea surface temperature estimates (SST) in the late Pliocene interval containing the M2 glaciation (ca. 3.250–3.3 Ma) by tying high resolution core measurements to a continuous downhole conductivity log. In addition, we provide new stable isotopic and alkenone measurements that correlate well to the revised splices of color reflectance and gamma ray attenuation porosity evaluator data. A new composite splice is proposed, along with composite isotope and alkenone time series that should be integrated into revised Pliocene paleoclimatic stacks.

scholarly journals A multivariate climate index for the western coast of Colombia

2013 ◽  
Vol 33 ◽  
pp. 21-26 ◽  
Author(s):  
E. Rodríguez-Rubio
Keyword(s):  
Time Series ◽  
Equatorial Pacific ◽  
Sea Surface ◽  
Climate Index ◽  
Western Coast ◽  
Coastal Station ◽  
Orthogonal Function ◽  
Sst Variability ◽  
Eastern Equatorial Pacific ◽  
Explained Variance

Abstract. Indices of the interannual and interdecadal variability at Tumaco Island (2° N; 79° W; Colombia), based on time series of sea surface temperature (SST), air temperature (AT) and precipitation (P) from a coastal station, are presented regarding the period 1960–2010. These indices are derived from the first two EOF (empirical orthogonal function) modes of the normalized time series, which grasp 84% of the explained variance. The first EOF represents the interannual variability closely correlated with the ENSO-related SST variability of region Niño 1+2 (r = 0.74; lag = 1), Niño 3 (r = 0.71; lag = 1), and the well-known period band 2–8 yr. Furthermore, the first EOF also accounts for the extreme warm events in the eastern equatorial Pacific due to them being well correlated with the E index (r = 0.70). The second EOF represents a much longer variability dominated by the ENSO-like mode or Pacific Decadal Oscillation (PDO), represented by two interdecadal modes (8–16 yr and 20–30 yr), and may account also with moderate warm events and cool events, being more sensitive to cool events.

EXTREME VALUES OF SEA SURFACE TEMPERATURE ASSOCIATED WITH LONG-PERIOD PHENOMENA OCCURRED DURING 1960-2015 IN THE COLOMBIAN PACIFIC OCEAN

2017 ◽  
Author(s):  
Diaz Juan Navia ◽  
Diaz Juan Navia ◽  
Bolaños Nancy Villegas ◽  
Bolaños Nancy Villegas ◽  
Igor Malikov ◽  
...  
Keyword(s):  
Time Series ◽  
Pacific Ocean ◽  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Extreme Values ◽  
Sea Surface ◽  
Absolute Maximum ◽  
Data Set ◽  
Arctic Oscillation Index ◽  
Colombian Pacific

Sea Surface Temperature Anomalies (SSTA), in four coastal hydrographic stations of Colombian Pacific Ocean, were analyzed. The selected hydrographic stations were: Tumaco (1°48'N-78°45'W), Gorgona island (2°58'N-78°11'W), Solano Bay (6°13'N-77°24'W) and Malpelo island (4°0'N-81°36'W). SSTA time series for 1960-2015 were calculated from monthly Sea Surface Temperature obtained from International Comprehensive Ocean Atmosphere Data Set (ICOADS). SSTA time series, Oceanic Nino Index (ONI), Pacific Decadal Oscillation index (PDO), Arctic Oscillation index (AO) and sunspots number (associated to solar activity), were compared. It was found that the SSTA absolute minimum has occurred in Tumaco (-3.93°C) in March 2009, in Gorgona (-3.71°C) in October 2007, in Solano Bay (-4.23°C) in April 2014 and Malpelo (-4.21°C) in December 2005. The SSTA absolute maximum was observed in Tumaco (3.45°C) in January 2002, in Gorgona (5.01°C) in July 1978, in Solano Bay (5.27°C) in March 1998 and Malpelo (3.64°C) in July 2015. A high correlation between SST and ONI in large part of study period, followed by a good correlation with PDO, was identified. The AO and SSTA have showed an inverse relationship in some periods. Solar Cycle has showed to be a modulator of behavior of SSTA in the selected stations. It was determined that extreme values of SST are related to the analyzed large scale oscillations.

scholarly journals Interpretation of the Chemical and Physical Time-Series Retrieved from Sentik Glacier, Ladakh Himalaya, India

1984 ◽  
Vol 30 (104) ◽  
pp. 66-76 ◽  
Author(s):  
Paul A. Mayewski ◽  
W. Berry Lyons ◽  
N. Ahmad ◽  
Gordon Smith ◽  
M. Pourchet
Keyword(s):  
Time Series ◽  
Chemical Species ◽  
Data Sets ◽  
Reactive Iron ◽  
Physical Time ◽  
Ladakh Himalaya ◽  
Data Density ◽  
Mass Circulation ◽  
The Himalaya ◽  
Analysis Of Time Series

AbstractSpectral analysis of time series of a c. 17 ± 0.3 year core, calibrated for total ß activity recovered from Sentik Glacier (4908m) Ladakh, Himalaya, yields several recognizable periodicities including subannual, annual, and multi-annual. The time-series, include both chemical data (chloride, sodium, reactive iron, reactive silicate, reactive phosphate, ammonium, δD, δ(18O) and pH) and physical data (density, debris and ice-band locations, and microparticles in size grades 0.50 to 12.70 μm). Source areas for chemical species investigated and general air-mass circulation defined from chemical and physical time-series are discussed to demonstrate the potential of such studies in the development of paleometeorological data sets from remote high-alpine glacierized sites such as the Himalaya.

scholarly journals An edge-cloud collaboration architecture for pattern anomaly detection of time series in wireless sensor networks

2021 ◽  
Author(s):  
Cong Gao ◽  
Ping Yang ◽  
Yanping Chen ◽  
Zhongmin Wang ◽  
Yue Wang
Keyword(s):  
Time Series ◽  
Wireless Sensor Networks ◽  
Sensor Networks ◽  
Anomaly Detection ◽  
Estimation Method ◽  
Feature Representation ◽  
Sensor Data ◽  
Wireless Sensor ◽  
Data Sets ◽  
Edge Node

AbstractWith large deployment of wireless sensor networks, anomaly detection for sensor data is becoming increasingly important in various fields. As a vital data form of sensor data, time series has three main types of anomaly: point anomaly, pattern anomaly, and sequence anomaly. In production environments, the analysis of pattern anomaly is the most rewarding one. However, the traditional processing model cloud computing is crippled in front of large amount of widely distributed data. This paper presents an edge-cloud collaboration architecture for pattern anomaly detection of time series. A task migration algorithm is developed to alleviate the problem of backlogged detection tasks at edge node. Besides, the detection tasks related to long-term correlation and short-term correlation in time series are allocated to cloud and edge node, respectively. A multi-dimensional feature representation scheme is devised to conduct efficient dimension reduction. Two key components of the feature representation trend identification and feature point extraction are elaborated. Based on the result of feature representation, pattern anomaly detection is performed with an improved kernel density estimation method. Finally, extensive experiments are conducted with synthetic data sets and real-world data sets.

Sign in / Sign up

Export Citation Format

Share Document