Northwest Africa and Southeast Australia are regions which are particularly vulnerable to climate change. In her thesis, Raquel Lopes dos Santos of the Royal Netherlands Institute for Sea Research, investigate organic compounds in marine sediment cores, in order to reconstruct past environmental conditions in these areas. She found that vegetation changes were large and abrupt over the past 150,000 years in these regions and were caused by climate change as well as indirectly by humans. Lopes dos Santos will defend her thesis at the Utrecht University, on 17 December, 2012.

“Organic matter will be  consumed by the ocean floor organisms if the ‘quality’ is good enough”, stated Lara Pozzato in her PhD Thesis. The quality is more important than, for exemple, the amount of oxygen in the environment. Pozzato studied the interactions among organic matter and organisms at sea floors in different settings. She will defend her PhD thesis on November 16, at the Utrecht University.

The amount of dissolved iron in the surface water of some parts of the Antarctic Ocean is so small that it limits algal growth. In the Arctic Ocean, iron concentrations are higher due to the influence of rivers. Maarten Klunder measured iron concentrations in various parts and at various depths of the Arctic Ocean. In addition, he ascertained where the iron came from. On 5 October 2012, Klunder will defend his PhD thesis on this research project at the University of Groningen.

About 50 million years ago, the Antarctic summer was subtropical, winter temperatures were above freezing and there was a tropical rainforest on the coast. These are the remarkable results of a research cruise to eastern Antarctica aboard a drilling vessel, led by expedition leader Henk Brinkhuis from Utrecht University and the Royal Netherlands Institute for Sea Research. The international research team will publish their results in the authoritative scientific journal Nature later this week.