Geoscientists from Australia and France have used the geological record of Earth’s deep oceans to discover a connection between the orbits of our home planet and Mars. They’ve discovered a surprising 2.4-million-year cycle where deep currents wax and wane which, in turn, is linked to periods of increased solar energy and a warmer climate.
“In 1976, scientists demonstrated for the first time the presence of 10,000 – 100,000-year astronomical cycles in Pleistocene deep-sea sediments, confirming Milutin Milankovitch’s theory that Earth’s climate is modulated by periodicities in perturbations of Earth’s orbit around the Sun and Earth’s spin axis,” said University of Sydney researcher Adriana Dutkiewicz and her colleagues.
“Apart from the well-known astronomical cycles with periods of 19,000, 23,000, 41,000, 100,000, and 400,000 years that pace Earth’s climate, the geological record also contains signals of much longer-period grand cycles, which are predicted by astronomical theory.”
“These grand cycles include orbitally-forced periodicities of millions and even tens of millions of years that are similarly linked to changes in incoming solar energy and paleoclimate.”
In their new research, the authors used the deep-sea sediment record to check for links between sedimentary shifts and changes in the Earth’s orbit.
They found that the vigor of deep-sea currents shifts in 2.4-million-year cycles.
“We were surprised to find these 2.4-million-year cycles in our deep-sea sedimentary data,” Dr. Dutkiewicz said.
“There is only one way to explain them: they are linked to cycles in the interactions of Mars and Earth orbiting the Sun.”
“The gravity fields of the planets in the solar system interfere with each other and this interaction, called a resonance, changes planetary eccentricity, a measure of how close to circular their orbits are.”
“For the Earth it means periods of higher incoming solar radiation and warmer climate in…
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