No Light Syrup – Global Warming?

My friends and I have been making maple syrup for nearly 30 years.  We don’t have any records from when we began so we aren’t quite sure what year we did it the first time.  We do it on a small scale outdoors on a crude fireplace.  But it gets us out of the house and into the fresh air when we might otherwise prefer to be inside by the fireplace.

Since 1989, however, we do have some records such as when we tapped the trees, when we boiled sap for the first time, and the quantity produced each year.  We even have some anecdotal data as to the quality of the sap we produced.   Quality is generally judged by the color of the syrup produced.  The highest quality is very light amber in color and gives a sweet buttery flavor.  As the season progresses the color gets progressively darker – a deep brown almost black color.  And the taste has a much more pronounced “maple” flavor.

The date of our first boil each year varies depending on the weather, but the date of the first boil has been reasonably consistent over the years.  Last year we only had one boil in which the color of the syrup was light.  In 2009 we had no boils that resulted in light color syrup.  We have a theory that global warming has come to the sugar bush in Indiana.

I have a friend who is still not convinced that the earth is warming and more particularly that the burning of fossil fuels is causing it.  I, on the other hand, am convinced that the earth is warming and that we are the cause of it.

I recently read a fascinating book, The Long Thaw, by David Archer, a professor of geophysical sciences at the University of Chicago.  While most of us who think about climate change think in terms of years and even a century, Archer speaks in terms of hundreds of millennia.  It is a gutsy book that brings a great many research facts to bear and in an unemotional manner presents the scenarios our ancestors can expect if we continue to change the temperature of the planet.  What follows are a number of quotes from the book that should get us to seriously consider this issue.

“Just in the last few decades, the temperature of the atmosphere has begun to rise in a way that can be explained only by the greenhouse theory, which has implication that it will get even warmer if CO₂ continues to rise.”

“Global warming could be one of human kind’s longest lasting legacies.  The climatic impacts of releasing fossil fuel CO₂ to the atmosphere will last longer than Stonehenge.  Longer than time capsules, longer than nuclear waste, far longer than the age of human civilization so far.”

“…The climate changes that civilized humanity has witnessed have been 1° C or less.”

“By the year 2100, traditional oil and gas will be gone.  It may take a few centuries to burn all the coal, however, and the coal is where most of the carbon is.”

“Mankind is becoming a force in climate comparable to the orbital variations that drive the glacial cycles.”

“The slow progression between hothouse and icy climates is driven by the cycling of CO₂ into and out of the solid Earth.  CO₂ is released from the Earth in volcanic gases and hot springs at the bottom of the ocean.  CO₂ is taken up by weathering reactions, the same reactions that will generate the long tail of the fossil fuel CO₂.”

“Volcanoes release much less CO₂ every year than we do, so the near term future is going to be dominated by us.”

“The sea level rise forecast for the coming century is 0.2 to about 0.6 meters.  This forecast includes the effects of water expanding as it warms up and the water from melting mountain glaciers in places like Alaska.  The forecast explicitly does not include what will ultimately be the most important process – the melting of major ice sheets in Greenland and Antarctica.”

“Ice sheet models … do predict the eventual melting of Greenland if the local summertime temperature were 3° C warmer.  Greenland by itself would raise sea level by 7 meters if it melted.”

“Our fossil fuel deposits, 100 million years old, could be gone in a few centuries, leaving climate impacts that will last for hundreds of millennia.” 

“Because there is so much coal on Earth, the climate of the future will be decided by what happens to coal.”

I distinctly remember reading in my big old geography book in 5^th grade that we have enough coal deposits to last another 200 years.  At the time, part of my job at school and at home was to shovel coal into the furnaces heating my school and my house.  I remembered thinking that 200 years is not a very long time.  I wondered what we would do when the coal ran out.

Well we haven’t yet run out, but we dare not burn what is left if we have any hope of not irreversibly changing the climate of our planet.

As engineers, can there be a more important challenge for us to tackle?  How can we provide the present energy intensive life style for a growing world population without destroying the earth’s climate?  Are we up to the task?