Related papers: An additional planet as a model for the Pleistocen…
Mammoths lived in Arctic East Siberia. In this region there is not sufficient sunlight over the year for the growth of the plants on which these animals feed. Therefore the latitude of this region was lower before the end of the…
In Arctic East Siberia many remains of mammoths have been found. In this region there is not sufficient sunlight over the year to allow for the growth of the plants on which these animals feed. Consequently the latitude of these regions…
The astronomical theory of Milankovitch relates the changes of Earth' past climate to variations in insolation caused by oscillations of the orbital parameters. However, this theory has problems to account for some major observed phenomena…
The striking asymmetry of the ice cover during the Last Global Maximum suggests that the North Pole was in Greenland and then rapidly shifted to its present position in the Arctic See. A scenario which causes such a rapid geographic polar…
We present a phase-space model that simulates Pleistocene ice volume changes based on Earth's orbital parameters. Terminations in the model are triggered by a combination of ice volume and orbital forcing and agree well with age estimates…
As is well known, during the Last Glacial Maximum, about 20'000 years ago, the ice was asymmetrically distributed around the present North Pole. It reached the region of New York, while east Siberia remained ice free. Mammoths lived in…
The Milankovitch theory states that the orbital eccentricity, precession, and obliquity of the Earth influence our climate by modulating the summer insolation at high latitudes in the northern hemisphere. Despite considerable success of…
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…
The Mid-Pleistocene Transition, the shift from 41 kyr to 100 kyr glacial-interglacial cycles that occurred roughly 1 Myr ago, is often considered as a change in internal climate dynamics. Here we revisit the model of Quaternary climate…
The glacial cycles are attributed to the climatic response of the orbital changes in the irradiance to the Earth. These changes in the forcing are to small to explain the observed climate variations as simple linear responses. Non-linear…
A comparison of northern and southern hemispheric paleotemperature profiles suggests that the Bolling-Allerod Interstadial, Younger Dryas stadial, and subsequent Preboreal warming which occurred at the end of the last ice age were…
Ice sheets appeared in the northern hemisphere around 3 million years ago and glacial-interglacial cycles have paced Earth's climate since then. Superimposed on these long glacial cycles comes an intricate pattern of millennial and…
"With five parameters one can fit an elephant". This provocative statement expresses the fact that when a theory has several adjustable parameters, an agreement with empirical data can be of modest value. What about a theory which contains…
The layered polar caps of Mars have long been thought to be related to variations in orbit and axial tilt. We dynamically link Mars's past climate variations with the stratigraphy and isotopic composition of its ice by modeling the exchange…
From the Archean toward the Proterozoic, the Earth's atmosphere underwent a major shift from anoxic to oxic conditions, around 2.4 to 2.1 Gyr, known as the Great Oxidation Event (GOE). This rapid transition may be related to an atmospheric…
The nature of the early Martian climate is one of the major unanswered questions of planetary science. Key challenges remain, but a new wave of orbital and in situ observations and improvements in climate modeling have led to significant…
For a hypothetical planet on a highly eccentric orbit, we have calculated the osculating orbital parameters and its closest approaches to Earth and Moon over a period of 750 kyr. The approaches which are close enough to influence the…
Paleoclimate data help us assess climate sensitivity and potential human-made climate effects. We conclude that Earth in the warmest interglacial periods of the past million years was less than 1{\deg}C warmer than in the Holocene. Polar…
The timeline of the Earth's history reveals quasi-periodicity of the geological record over the last 542 Myr, on timescales close, in the order of magnitude, to 1 Myr. What is the origin of this quasi-periodicity? What is the nature of the…
Our solar system's path has recently been shown to potentially intersect dense interstellar clouds 2 and 7 million years ago: the Local Lynx of Cold Cloud and the edge of the Local Bubble. These clouds compressed the heliosphere, directly…