Tag Archives: algae

No snow at Christmas?

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Norwegian Arctic (Image by Sarah)

The algae in the Arctic Ocean are blooming earlier every year at the moment because the sea ice melts more quickly each Spring as a consequence of global warming. This observation was made by Kevin Arrigo, a biological oceanographer at Stanford University and confirmed by Mati Kahru, an oceanographer at the University of California, San Diego using satellite imaging. But what’s good for algae is not good for polar bears or us because less ice deprives polar bears of a hunting platform and raises sea levels globally. A 1m rise in sea level would displace 145 million people, or the equivalent of about half the population of the USA. A 2 degree temperature rise would make the Earth as warm as 3 million years ago when sea levels were between 25m and 35m higher – the temperature in the Arctic in last month was 2.22°C above average for the time of year.  The extent of the sea ice in October was 28.5% less than average for the month. So while there will be snow at Christmas in the Arctic, there might not be in the future.

Our current engineering technology is both contributing to climate change and is inadequate to mitigate the consequences. These issues present a series of great opportunities disguised as insoluble problems (quoting John Gardiner), and given the predictions of the UN Intergovernmental Panel, we have less than 40 years to replace the equivalent of 200 years of engineering development (paraphrasing Yoshiyuki Sakaki). So, the generation of students entering engineering at the moment are going to be engaged in race that’s more challenging and more important to society than the race to the moon that preoccupied the generation that preceded mine.

Sources

Carl Zimmer, Global warming altering the Arctic food chain, Taipei Times, November 27th, 2016.

Blockstein DE, Weigman L, The Climate Solutions Consensus. Island Press, Washington, 2010.

John Gardiner, founder of Common Cause cited in Friedman, Thomas L., Hot, Flat and CrowdedWhy we need a green revolution and how it can renew America, Farrar, Straus & Giroux, New York, 2008.

Yoshiyuki Sakaki, President, Toyohashi University of Technology, Japan, Keynote presentation at ICEE/ICEER conference in Seoul, Korea, 25th August 2009.

Opal offers validation opportunity for climate models

OrangeFanSpongeSmallMany of us will be familiar with the concept of the carbon cycle, but what about the silicon cycle?  Silicon is the second most abundant element in the Earth’s crust.  As a consequence of erosion, it is carried by rivers into the sea where organisms, such as sponges and diatoms (photosynthetic algae), convert the silicon in seawater into opal that ends up in ocean sediment when these organisms die.  This marine silicon cycle can be incorporated into climate models, since each step is influenced by climatic conditions, and the opal sediment distribution from deep sea sediment cores can be used for model validation.

This approach can assist in providing additional confidence in climate models, which are notoriously difficult to validate, and was described by Katharine Hendry, a Royal Society University Research Fellow at the University of Bristol at a recent conference at the Royal Society.  This struck me as an out-of-the box or lateral way of seeking to increase confidence in climate models.

There are many examples in engineering where we tend to shy away from comprehensive validation of computational models because the acquisition of measured data seems too difficult and, or expensive.  We should take inspiration from sponges – by looking for data that is not necessarily the objective of the modelling but that nevertheless characterises the model’s behaviour.

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