Investigations into the impact of astronomical phenomena on the terrestrial biosphere and climate
This thesis assesses the influence of astronomical phenomena on the Earth's biosphere and climate. I examine in particular the relevance of both the path of the Sun through the Galaxy and the evolution of the Earth's orbital parameters in modulating non-terrestrial mechanisms. I build mode...
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ftdatacite:10.48550/arxiv.1505.07856 2023-05-15T16:41:29+02:00 Investigations into the impact of astronomical phenomena on the terrestrial biosphere and climate Feng, Fabo 2015 https://dx.doi.org/10.48550/arxiv.1505.07856 https://arxiv.org/abs/1505.07856 unknown arXiv arXiv.org perpetual, non-exclusive license http://arxiv.org/licenses/nonexclusive-distrib/1.0/ Earth and Planetary Astrophysics astro-ph.EP Astrophysics of Galaxies astro-ph.GA Atmospheric and Oceanic Physics physics.ao-ph FOS Physical sciences Preprint Article article CreativeWork 2015 ftdatacite https://doi.org/10.48550/arxiv.1505.07856 2022-04-01T12:16:33Z This thesis assesses the influence of astronomical phenomena on the Earth's biosphere and climate. I examine in particular the relevance of both the path of the Sun through the Galaxy and the evolution of the Earth's orbital parameters in modulating non-terrestrial mechanisms. I build models to predict the extinction rate of species, the temporal variation of the impact cratering rate and ice sheet deglaciations, and then compare these models with other models within a Bayesian framework. I find that the temporal distribution of mass extinction events over the past 550 Myr can be explained just as well by a uniform random distribution as by other models, such as variations in the stellar density local to the Sun arising from the Sun's orbit. Given the uncertainties in the Galaxy model and the Sun's current phase space coordinates, as well as the errors in the geological data, it is not possible to draw a clear connection between terrestrial extinction and the solar motion. In a separate study, I find that the solar motion, which modulates the Galactic tidal forces imposed on Oort cloud comets, does not significantly influence this cratering rate. My dynamical models, together with the solar apex motion, can explain the anisotropic perihelia of long period comets without needing to invoke the existence of a Jupiter-mass solar companion. Finally, I find that variations in the Earth's obliquity play a dominant role in triggering terrestrial deglaciations over the past 2 Myr. The precession of the equinoxes, in contrast, only becomes important in pacing large deglaciations after the transition from the 100-kyr dominant periodicity in the ice coverage to a 41-kyr dominant periodicity, which occurred 0.7 Myr ago. : 147 pages, 45 figures, PhD thesis, deposited in HeiDOK by Heidelberg University Library Report Ice Sheet DataCite Metadata Store (German National Library of Science and Technology) Jupiter ENVELOPE(101.133,101.133,-66.117,-66.117) |
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DataCite Metadata Store (German National Library of Science and Technology) |
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Earth and Planetary Astrophysics astro-ph.EP Astrophysics of Galaxies astro-ph.GA Atmospheric and Oceanic Physics physics.ao-ph FOS Physical sciences |
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Earth and Planetary Astrophysics astro-ph.EP Astrophysics of Galaxies astro-ph.GA Atmospheric and Oceanic Physics physics.ao-ph FOS Physical sciences Feng, Fabo Investigations into the impact of astronomical phenomena on the terrestrial biosphere and climate |
topic_facet |
Earth and Planetary Astrophysics astro-ph.EP Astrophysics of Galaxies astro-ph.GA Atmospheric and Oceanic Physics physics.ao-ph FOS Physical sciences |
description |
This thesis assesses the influence of astronomical phenomena on the Earth's biosphere and climate. I examine in particular the relevance of both the path of the Sun through the Galaxy and the evolution of the Earth's orbital parameters in modulating non-terrestrial mechanisms. I build models to predict the extinction rate of species, the temporal variation of the impact cratering rate and ice sheet deglaciations, and then compare these models with other models within a Bayesian framework. I find that the temporal distribution of mass extinction events over the past 550 Myr can be explained just as well by a uniform random distribution as by other models, such as variations in the stellar density local to the Sun arising from the Sun's orbit. Given the uncertainties in the Galaxy model and the Sun's current phase space coordinates, as well as the errors in the geological data, it is not possible to draw a clear connection between terrestrial extinction and the solar motion. In a separate study, I find that the solar motion, which modulates the Galactic tidal forces imposed on Oort cloud comets, does not significantly influence this cratering rate. My dynamical models, together with the solar apex motion, can explain the anisotropic perihelia of long period comets without needing to invoke the existence of a Jupiter-mass solar companion. Finally, I find that variations in the Earth's obliquity play a dominant role in triggering terrestrial deglaciations over the past 2 Myr. The precession of the equinoxes, in contrast, only becomes important in pacing large deglaciations after the transition from the 100-kyr dominant periodicity in the ice coverage to a 41-kyr dominant periodicity, which occurred 0.7 Myr ago. : 147 pages, 45 figures, PhD thesis, deposited in HeiDOK by Heidelberg University Library |
format |
Report |
author |
Feng, Fabo |
author_facet |
Feng, Fabo |
author_sort |
Feng, Fabo |
title |
Investigations into the impact of astronomical phenomena on the terrestrial biosphere and climate |
title_short |
Investigations into the impact of astronomical phenomena on the terrestrial biosphere and climate |
title_full |
Investigations into the impact of astronomical phenomena on the terrestrial biosphere and climate |
title_fullStr |
Investigations into the impact of astronomical phenomena on the terrestrial biosphere and climate |
title_full_unstemmed |
Investigations into the impact of astronomical phenomena on the terrestrial biosphere and climate |
title_sort |
investigations into the impact of astronomical phenomena on the terrestrial biosphere and climate |
publisher |
arXiv |
publishDate |
2015 |
url |
https://dx.doi.org/10.48550/arxiv.1505.07856 https://arxiv.org/abs/1505.07856 |
long_lat |
ENVELOPE(101.133,101.133,-66.117,-66.117) |
geographic |
Jupiter |
geographic_facet |
Jupiter |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_rights |
arXiv.org perpetual, non-exclusive license http://arxiv.org/licenses/nonexclusive-distrib/1.0/ |
op_doi |
https://doi.org/10.48550/arxiv.1505.07856 |
_version_ |
1766031927980064768 |