This seminal 1976 paper tested the Milnkovitch orbital forcing hypothesis by comparing the 450,000 year geological record of the climate as recorded in marine sediments with the cycle of variations in Earth’s tilt and orbit. The analysis finds clear evidence for orbital forcing in the marine sediment record, but the authors conclude that orbital forcing by itself is not able to explain the dominant 100,000 year glacial/deglacial cycle.
A reanalysis of the effect of black carbon emissions has found that it is second only to carbon dioxide emissions in its warming impact on the climate. Together carbon dioxide, black carbon, and methane emissions represent the anthropogenic sources with the largest impact on Earth’s climate.
A recent study of ice cores from Antarctica provides a climate record for the past 800,000 years. The analysis reveals that atmospheric carbon dioxide was strongly correlated with Antarctic temperature throughout eight glacial cycles.
A recent study has created a simple mathematical rule that can account for the timing of the onset of interglacials following ice ages over the past three million years. The rule is based on predictable long-term astronomical variations in the Earth’s orbit and tilt called Milankovitch cycles.