A study conducted by Dr. Thomas Stevens and his team from the Department of Geography at Royal Holloway, University of London, shows that a change in the level of salt in the Pacific Ocean could have been the root of the cause behind the Quaternary ice age that took place over two and a half million years ago. The findings of the experiment were published in the journal Nature’s Scientific Reports and have recently been summarized for an article completed by Science Daily.
Dr. Stevens and his team studied a variety of samples in a dust entitled red clay that accumulated in north central China between six million and two and a half million years ago. Using this dust, the researchers were able to reconstruct a course of events that resulted in the creation of ice sheets in the Northern Hemisphere; some of these sheets ultimately developed to reach a thickness of three kilometers.
From this dust, a clear course of events to the ice sheets emerged. The level of salt evident in the Pacific Ocean shifted fundamentally, causing the creation of sea ice. The replacement of ice instead of water changed the pattern of the wind, which, in turn, prompted intensified monsoons. The presence of intense precipitation in the cooling global temperatures surprised the researchers, as scientists often associate violent storms with warmer climates. However, an explanation became clear as they researched the interaction between plate tectonic moments brought on by the meeting of North and South America. The closing of the Panama Seaway and the increased wind patterns brought on a global cooling, which induced, in turn, a cyclical process of creating more sea ice and prompting heavier precipitation. From there, glaciers formed and monsoons turned to snowfall, eventually resulting in the accumulation of ice sheets.