An international team of scientists has discovered new relationships between deep-sea temperature and ice-volume changes to provide crucial new information about how the ice ages came about.
Researchers from the University of Southampton, the National Oceanography Centre and the Australian National University developed a new method for determining sea-level and deep-sea temperature variability over the past 5.3 million years. It provides new insight into the climatic relationships that caused the development of major ice-age cycles during the past two million years.
The researchers found, for the first time, that the long-term trends in cooling and continental ice-volume cycles over the past 5.3 million years were not the same. In fact, for temperature the major step toward the ice ages that have characterised the past two to three million years was a cooling event at 2.7 million years ago, but for ice-volume the crucial step was the development of the first intense ice age at around 2.15 million years ago. Before these results, these were thought to have occurred together at about 2.5 million years ago.
The results are published in the scientific journal Nature.
Starting An Ice Age
Follow us on Twitter
- Crucial new information about how the ice ages came about : PR & Podcast
- 2014 Sino-UK Coevolution of Life and the Planet Summer School
- Past and Future CO2 – Reconstructing atmospheric Carbon Dioxide
- Co-evolution of Life and the Planet conference in UCL and Geological Society London
- PR: What the geological evidence of the past tells us about modern sea-level rise