New research indicates that, absent human-induced climate change, Earth might have been on course for another glacial period in just 11,000 years. This prediction stems from a detailed analysis of how the planet’s orbital mechanisms influence solar energy distribution, drawing on the principles of Milankovitch cycles that have historically driven glacial and interglacial periods.
For millions of years, these natural oscillations allowed Earth to transition between glacial periods approximately every 41,000 years. However, in the last 800,000 years, ice ages have occurred roughly every 100,000 years. The term “ice age” encompasses any time period marked by polar ice, but it is often used to refer specifically to significant glaciation episodes.
Previous studies struggled to clarify how orbital changes contributed to this prolonged cycle, known as the “100,000-year problem.” In contrast, researchers adopted a broader approach, examining glacial patterns over time rather than correlating specific orbital shifts to distinct ice age events. This enabled them to establish meaningful connections between orbital variations and ice dynamics, despite inconsistencies in historical ice records.
The findings suggest a consistent pattern over the last 900,000 years, where every interglacial phase has followed a specific alignment of Earth’s axial tilt and orbital shape. This alignment indicates a predictive relationship between climate cycles and orbital characteristics, according to the research team.
According to the study, if greenhouse gas emissions were not a factor, the next interglacial period could be expected in approximately 66,000 years. However, this projection is contingent on the occurrence of a glacial period beforehand. Current projections suggest glaciation could begin within the next 11,000 years, although this scenario relies entirely on natural climate processes.
Human activities have released over 1.5 trillion tons of carbon dioxide into the atmosphere since the industrial revolution, significantly impacting long-term climate patterns. The current levels of greenhouse gases are anticipated to halt the natural onset of glacial periods for tens to hundreds of thousands of years.
Experts note that even pre-industrial CO2 concentrations might have been sufficient to postpone the advance of ice sheets by up to 50,000 years, due to minimal expected orbital changes and the complexity of Earth’s climatic responses. Ongoing research is crucial for refining our understanding of future climate scenarios.
Topics:
- climate change/
- global warming
