Home » Laser Diffraction, Mastersizer, Particle size

Measuring ancient ocean floor to illuminate climate change

24 February 2011 No Comment

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In the UK and US we recognize the idiom; ‘What goes around, comes around’, while the Russian equivalent is; ‘As the call, so the echo,’ and in this instance the Russian’s have the poetic edge in my opinion. However, the point that I am trying to raise is the idea that what has happened in the past can be reflected in the present and , if you happen to be working in the Earth sciences, you have the entire history of the planet, across geological time, to reference!

The cyclical nature of Earth’s climate enables scientists to tackle environmental questions of today by looking at ancient analogues in Earth’s past. By measuring grain size in samples of oceanic sediment using a Mastersizer particle size analyzer, climatologists have been able to gain insight into the scale and nature of the climate forcing resulting from modern pollutants.

The Paleocene-Eocene Thermal Maximum (PETM) as an analogue of today’s climate change

The most extreme change in Earth surface conditions during the most recent geological era began at the temporal boundary between the Paleocene and Eocene epochs. Referred to as the Paleocene-Eocene Thermal Maximum (PETM; 55Ma), scientists in the fields of oceanography and atmospherics consider this event to be a close ancient analog to modern global warming. As such, a great deal of information regarding current climate change concerns can be inferred by investigating environmental evidence laid down during this period.

In a presentation given at the 2010 fall meeting of the  American Geophysical Union, Professor T. Bralower and colleagues from Pennsylvania State University’s Geosciences department delivered a set of results under the heading; ‘High-resolution grain size analysis and its significance for detecting ocean acidification at the onset of the Paleocene-Eocene Thermal Maximum (PETM; 55Ma)’. Also published on 20 October 2010 in the EPOCA (European Project on Ocean Acidification) Ocean acidification blog, these results provide quantitative estimates of the changes in microscopic marine life in sea sediments deposited during the course of the PETM. These changes are indicative of the prevailing environmental conditions.

Meeting the needs of geoscientists

In the Pennsylvania State University and other work, the  Mastersizer system  has proved suitable  for delivering grain size analysis of samples such as ocean sediment. Capable of distinguishing large particles within a population of smaller ones, across a wide range of sample sizes, the Mastersizer’s inbuilt algorithm handles polydisperse samples with ease.

If you’re working in this field, we’d love to hear more about your experiences with particle size measurement.