Long-Term Monitoring Of Cyclic Frequency Variability in Rapidly Oscillating ap Stars at the Sutherland Station of The South African Astronomical Observatory

AbstractSubtropical ocean gyres play a key role in modulating the global climate system redistributing energy between low and high latitudes. A poleward displacement of the subtropical gyres has been observed over the last decades, but the lack of long-term monitoring data hinders an in-depth understanding of their dynamics. Paleoceanographic records offer the opportunity to identify meridional changes in the subtropical gyres and investigate their consequences to the climate system. Here we use the abundance of planktonic foraminiferal species Globorotalia truncatulinodes from a sediment core collected at the northernmost boundary of the South Atlantic Subtropical Gyre (SASG) together with a previously published record of the same species from the southernmost boundary of the SASG to reconstruct meridional fluctuations of the SASG over last ca. 70 kyr. Our findings indicate southward displacements of the SASG during Heinrich Stadials (HS) 6-4 and HS1, and a contraction of the SASG during HS3 and HS2. During HS6-4 and HS1, the SASG southward displacements likely boosted the transfer of heat to the Southern Ocean, ultimately strengthening deep-water upwelling and CO2 release to the atmosphere. We hypothesize that the ongoing SASG poleward displacement may further increase oceanic CO2 release.

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Long-Term Monitoring of Cyclic Frequency Variability in roAp Stars

Variable Stars as Essential Astrophysical Tools ◽

10.1007/978-94-011-4299-1_14 ◽

2000 ◽

pp. 363-372

Author(s):

D. W. Kurtz

Keyword(s):

Cyclic Frequency ◽

Long Term Monitoring ◽

Term Monitoring

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Long-Term Monitoring of Scots Pine Litter Decomposition Rates Throughout Sweden Indicates Formation of a More Recalcitrant Litter in the South

AMBIO ◽

10.1007/s13280-011-0202-0 ◽

2011 ◽

Vol 40 (8) ◽

pp. 878-890 ◽

Cited By ~ 3

Author(s):

Ewa Bringmark ◽

Lage Bringmark ◽

Lars Sonesten ◽

Kristina Mjöfors ◽

Maj-Britt Johansson

Keyword(s):

Litter Decomposition ◽

Scots Pine ◽

The South ◽

Decomposition Rates ◽

Long Term Monitoring ◽

Term Monitoring

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Meridional Changes in The South Atlantic Subtropical Gyre During Heinrich Stadials

10.21203/rs.3.rs-115324/v1 ◽

2020 ◽

Author(s):

Tainã Pinho ◽

Cristiano Chiessi ◽

Rodrigo Portilho-Ramos ◽

Marília Campos ◽

Stefano Crivellari ◽

...

Keyword(s):

Global Climate ◽

South Atlantic ◽

Subtropical Gyre ◽

Climate System ◽

The South ◽

Foraminiferal Species ◽

Ocean Gyres ◽

Long Term Monitoring ◽

Term Monitoring

Abstract Subtropical ocean gyres play a key role in modulating the global climate system redistributing energy between low and high latitudes. A poleward displacement of the subtropical gyres has been observed over the last decades, but the lack of long-term monitoring data hinders an in-depth understanding of their dynamics. Paleoceanographic records offer the opportunity to identify meridional changes in the subtropical gyres and investigate their consequences to the climate system. Here we use the abundance of planktonic foraminiferal species Globorotalia truncatulinodes from a sediment core collected at the northernmost boundary of the South Atlantic Subtropical Gyre (SASG) together with a previously published record of the same species from the southernmost boundary of the SASG to reconstruct meridional fluctuations of the SASG over last ca. 70 kyr. Our findings indicate southward displacements of the SASG during Heinrich Stadials (HS) 6-4 and HS1, and a contraction of the SASG during HS3 and HS2. During HS6-4 and HS1, the SASG southward displacements likely boosted the transfer of heat to the Southern Ocean, ultimately strengthening deep-water upwelling and CO2 release to the atmosphere. We hypothesize that the ongoing SASG poleward displacement may further increase oceanic CO2 release.

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Revealing Variety of Comets by Long-Term Monitoring Observation with a 50-cm Telescope

International Astronomical Union Colloquium ◽

10.1017/s0252921100079033 ◽

2001 ◽

Vol 183 ◽

pp. 265-270

Author(s):

Jun-ichi Watanabe ◽

Hideo Fukushima

Keyword(s):

Heliocentric Distance ◽

Temporal Variations ◽

Astronomical Observatory ◽

Long Term Monitoring ◽

Term Monitoring

AbstractWe have been monitoring comets using the 50-cm telescope at the Mitaka campus of the National Astronomical Observatory, Japan since 1996. Over 20 comets, including bright ones such as comet C/1995 O1(Hale-Bopp), have been observed over long-term periods, namely over large heliocentric distance scales. Our samples show variety of comets in terms of both morphological and temporal variations. Several typical examples of various morphology, probably due to dust, are shown to emphasize the importance of long-term monitoring of comets.

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