oceans

One of the big mysteries in the scientific world is how the ice sheets of Antarctica formed so rapidly about 34 million years ago, at the boundary between the Eocene and Oligocene epochs.

There are 2 competing theories:

The first explanation is based on global climate change: Scientists have shown that atmospheric carbon dioxide levels declined steadily since the beginning of the Cenozoic Era, 66 million years ago. Once CO2 dropped below a critical threshold, cooler global temperatures allowed the ice sheets of Antarctica to form.

Classified as: science, climate change, oceans, External, Antarctic, antarctica, Department of Earth and Planetary Sciences, Galen Halverson
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Published on: 31 Jan 2017

A team of researchers from McGill University and the Quebec government have discovered microplastics (in the form of polyethylene 'microbeads,' less than 2 mm in diameter) widely distributed across the bottom of the St. Lawrence River, the first time such pollutants have been found in freshwater sediments.

Classified as: Redpath Museum, Sustainability, McGill, Anthony Ricciardi, oceans, microplastics, contaminants, microbeads, pollution, St. Lawrence river
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Published on: 23 Sep 2014

The ocean the Titanic sailed through just over 100 years ago was very different from the one we swim in today. Global warming is increasing ocean temperatures and harming marine food webs. Nitrogen run-off from fertilizers is causing coastal dead zones. A McGill-led international research team has now completed the first global study of changes that occurred in a crucial component of ocean chemistry, the nitrogen cycle, at the end of the last ice age. The results of their study confirm that oceans are good at balancing the nitrogen cycle on a global scale. But the data also shows that it is a slow process that may take many centuries, or even millennia, raising worries about the effects of the scale and speed of current changes in the ocean.

Classified as: ice age, nitrogen cycle, ocean chemistry, oceans
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Published on: 13 Jun 2013