(This is the second in a 10-part series intended to look at some of the issues surrounding Guyana’s bid for funds from the World Bank-administered Forest Carbon Partnership Fund (FCPF) and from Norway, and for the President’s Low Carbon Development Strategy.)
By Janette Bulkan
Carbon as in the ‘Low-Carbon Development Strategy’ is only the latest manifestation of what may well prove to be a whimsical belief in ‘El Dorado’. What exactly is carbon? Mr Freddie Kissoon recently described one commonplace understanding of the meaning of ‘carbon’: “when I was a small boy in Wortmanville at Christmas we used to put carbide in empty cans, spit inside the tin and light it. It went off like a bomb. One day it went the wrong way and almost flew into my face. I was about eight years old then, and I ran home crying. Since then I have no interest in any kind of carbon” (Guyana – Kaieteur News. Columnist Freddie Kissoon. 19 June 2009. President Jagdeo was at UG. http://www.kaieteurnewsonline.com/2009/06/19/president-jagdeo-was-at-ug/). Coal and diamonds are two forms of elemental carbon; carbon stored in trees is another. In today’s column, we will review some basic information on the nature of carbon, and its place in global initiatives to address global warming.
What is carbon?
Carbon is a chemical element, which is depicted by the symbol ‘C’. Carbon is the fourth most abundant element in the universe by mass, and the second most abundant element in the human body by mass (about 18.5 percent) after oxygen. Carbon is present in all known life forms; its abundance, and its ability to form organic compounds like carbon dioxide (CO2), make this element one of the chemical bases of all known life. Carbon dioxide is the most abundant of the greenhouse gases (GHG) which are causing the planet to warm dangerously. The following are three key points about carbon and trees:
#1: Trees remove or sequester carbon dioxide from the atmosphere.
Carbon is constantly being exchanged between the atmosphere, the oceans and the land. Plants play an important role in this exchange: using the energy from sunlight, plants convert atmospheric carbon dioxide into plant food, stored as biomass in the form of various compounds of carbon. This conversion is called photosynthesis, and is one reason why forests feature prominently in the discussions on global warming. But trees also respire to release the energy needed for growth and for defence against pest attack, and this respiration returns almost as much CO2 to the atmosphere as is taken up by photosynthesis.
Many tree species are long-lived. Trees increase in size as they absorb more carbon from the atmosphere. A recent report ‘Increasing Carbon Storage in Intact African Tropical Forests’ published in the journal Nature (19 February 2009) estimates that tropical forests are absorbing nearly one-fifth of the global carbon dioxide released by burning fossil fuels. Eventually trees die and in decaying release their stored CO2 back to the atmosphere. So, in a natural forest undisturbed by human activity most of the trees are taking in CO2 by photosynthesis, respiring most of that CO2 to generate energy, and sequestering some of the CO2 in timber. But some old trees are dying and there is dead wood on the ground, and that is returning the stored CO2 back to the atmosphere. A mature forest undisturbed by human activity is mostly in equilibrium, with carbon gain and carbon loss almost exactly balanced. In terms of area, you can imagine that most of the natural forest is sequestering carbon but some patches of forest are naturally releasing more carbon through decomposition.
#2: Trees release carbon into the atmosphere when burnt
Trees contribute to global warming when trees are burnt, whether deliberately or accidentally, or when a tree ages and dies. In the case of forest fires, carbon is released rapidly; in the case of natural processes of decay and dying, the carbon is released slowly. As tropical forests are removed (deforestation) or degraded (which is technically a reversible process), the planet loses in two major inter-related ways: generally an irreversible loss of a critical carbon sink (the absorptive capacity of trees), and intensification of global warming, and all its catastrophic feedback effects.
#3: Trees provide multiple ecosystem benefits, beyond storing carbon
In addition to storing most of the planet’s above- and below-ground carbon, forests provide many significant environmental and sustainable development co-benefits including biodiversity conservation; watershed protection; reduction of runoff, siltation and flooding; protection of fisheries; and sustained livelihoods and incomes for indigenous peoples and local communities dependent on intact natural environments. These are in addition to commercial benefits from harvests of timber and non-wood forest products.
Greenhouse gases – roles in atmosphere
Greenhouse gases (GHGs) are those gases in the atmosphere that allow sunlight to reach the Earth, but slow down the outward flow of heat from Earth. Carbon dioxide (CO2) is the most abundant, making up 56 percent of the greenhouse gases, with methane making up another 16 percent. Carbon is released to the atmosphere when fossil fuels (coal, petroleum), and trees, are burned. Carbon emissions from deforestation and forest degradation in developing countries make up about one-fifth of the total global emissions of GHGs every year.
Changes in GHG emissions
– historical, present
Every year human activities add about 30 billion tonnes of CO2 to the atmosphere. From studying climate records, scientists have established that half of this CO2 accumulates in the atmosphere. The concentration of CO2 in the atmosphere has risen by a little over 1/3 from the beginning of the Industrial Revolution (c. 1750): from 270 parts per million (ppm) to 384 ppm – or from 2.2 trillion tonnes to almost 3 trillion tonnes globally. It is only when those figures are disaggregated that we can fully appreciate the alarming accelerations in CO2 emissions over the last fifty years. Between 1750 and 1952, CO2 levels increased by 45 ppm. In the following 40 year-period — from 1952 to 1991 — the rate of CO2 emissions quintupled to 1 ppm a year – as another 40 ppm were added to the atmosphere. Then, in the past 15 years, from 1991 to 2006, the rate of increase doubled again with 30 ppm, or 2 ppm a year, added in 15 years. This is an exponential rate of increase, and starkly underlines why urgent action is needed.
There are two important points to add: For a long time, it was widely, and mistakenly, thought that the ocean would absorb nearly all the industrial CO2 released particularly over the past 250 years after the invention of machinery powered by coal, or fossil fuels. Scientists later established that because of the slowness of ocean uptake, CO2 concentrations will take decades and centuries to come back down, even if humans stop emitting CO2 immediately. Roughly 15 percent of the carbon we emit will still be in the atmosphere 500 years from now. Secondly, simply stabilizing CO2 at the present concentration requires a reduction in current emissions of around 60 percent, and because of climate feedbacks, the reduction may need to be closer to 80 percent in the long term. I shall look at when and how carbon became a tradable commodity in my next column.
