Contemplating Humanity’s Carbon Use Efficiency

Saint Paul’s Hospital

A Little Science…
I’ve spent today thinking about efficiency, namely, iron (Fe) use efficiency by phytoplankton (single celled photosynthetic organisms). Iron is primarily involved in a variety of metabolic processes, notably photosynthesis and respiration (i.e. making your cake and eating it too). In fact, around 90% of the Fe in a phytoplankton cell is found within the chloroplast – a subcellular compartment where light energy is harvested into chemical energy. Basically, without Fe, phytoplankton (like all living things – especially anemics) would perish.

Vast areas of the open ocean receive such sparing amounts of Fe that the seed phytoplankton population is unable to totally use up all the other nutrients available to it. In fact, 30% of global ocean is limited by Fe, and this limitation is thought to be of utmost importance in controlling atmospheric carbon dioxide levels over geological time through the biological pump (i.e. phytoplankton turn CO2 into sugars, then sink below the surface mixed layer of the ocean that is contact with the atmosphere, die, and thus act as a vector to sequester CO2 away from the atmosphere).

Interestingly, however, there are phytoplankton that reside in these “oceanic deserts”. How, you may ask? Well, laboratory studies of individual species isolated from marine environments characterized by high and low Fe concentrations have elucidated a number physiological mechanisms that make the “desert” species capable of thriving. The most straight forward example is: evolve to use less of it! Indeed, by making use of a physiological index called the Fe Use Efficiency (IUE), one can determine the amount of carbon a cell can turn into sugar for every atom of cellular Fe. Basically, when limited by Fe, the higher your IUE, the better you are at making a living in the Fe-limited photosynthetic world.

…And Everything Else
I’ve probably walked past Saint Paul’s 1000 times – or once every 1.8 days for 5 years. This is my fifth Christmas in Vancouver, and the fifth time I’ve had the pleasure to see the giant spectacle of Christmas lights outside the hospital downtown. I usually spend hours studying at the coffee shop across the street – watching dozens of people stand and stare at the 3 story castle of colour, while a few professional photographers set up their tripods and tinker with their camera’s f-stops and shutter speeds to catch that perfect shot they might monger off onto a post card company.

Then, I usually catch myself drifting off into my childhood memories. I remember building a giant snow throne in the 4 to 5 foot snow drifts that had accumulated on our front lawn, feeding my dad the long string of Christmas lights that we had spent the entire morning checking for burnt bulbs. He would snag the line onto a bent nail hammered into the end of my hockey stick, and attempt to string up the two 6 meter spruce trees standing on each side of our front walk. Then, that night when it was dark enough outside, we would all go outside while he plugged the extension cord in and watch our quantized creation come to life.

Tonight, as I walked home past the hospital and the lights and the young teenage couple standing under the walkway and the older couple sitting on the bench, I thought to myself, “I wonder how much energy is required to light these every season? How much carbon is being used up just to light this display?”

I stopped in stride. “How could I ask myself such a ridiculous questions – who cares, its beautiful!” I thought, “Look how many people are enjoying it, this symbol of bliss and happiness that has marked a dozen of your childhood winter seasons!” I took a picture with my camera, and walked home.

How much are we willing to sacrifice for the “Go green or go home!” or the zero-carbon footprint mantras? Any extraneous use of energy is arguably a waste of energy in the “we’ve only got only planet” mindset. However, is the world willing to give up all unnecessary uses of energy – from lighting up St. Paul’s Hospital to manufacturing art supplies, from electro-graf to interactive architecture. How can humanity improve its carbon use efficiency? How can we (royal we) thrive socially, culturally, and economically in a carbon-limiting world? Ultimately, a drastic change in the way we think about energy, its uses, and what we truly value about the way we currently live is of order.

If tomorrow, all uses of energy beyond what were absolutely essential to humanity’s survival were banned, what would you want to be saved?

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Dave Semeniuk spends hours locked up in his office, thinking about the role the oceans play in controlling global climate, and unique ways of studying it. He'd also like to shamelessly plug his art practice: