There are numerous, in-depth reports about climate change from scientific communities and governmental committees. Some of the most prominent are listed at the end of this paper. Many reports detail the causes and outcomes of greenhouse gasses (GHGs) and rising atmospheric temperatures. Others, such as the 2018 special report by the IPCC, provide detailed scenarios for potential mitigation (slowing or ceasing CO2 emissions within given timeframes) and interventions (such as removing CO2 from the atmosphere.) Due to the extent of existing climate science, this paper will focus on issues related to next steps, particularly with respect to human use of energy. What would it mean to cease use of fossil fuels, and what alternatives are there? Do we have the sense of urgency, and the political will, to face the needed changes?
At present, the Paris Agreement represents the highest level of intergovernmental cooperation about climate change to be achieved. Despite the agreement, however, global use of fossil fuels has continued to increase. According to a report by BP (2019), in 2018 primary energy consumption grew at a rate of 2.9%, almost double its ten-year average. As a result, carbon emissions grew by 2%, the highest rate in seven years. Collectively, India, China and the US accounted for two-thirds of the increases in energy demands.
While the science may seem clear, the political will for change does not yet exist. As noted, we have yet to begin any meaningful reductions in the use of fossil fuels. One of the key questions is, how much energy do we actually need?
At the level of survival, a moderately active adult needs about 8-11 MJ (mega joules) of food per day. 8.37 MJ equates to 2000 Calories (kilocalories), which is about 100 Watts of electricity – enough to power a 100 Watt incandescent light bulb for an hour.
Smil (2018) has estimated minimum and maximum amounts for modern societies. According to his calculations, “No country whose annual primary commercial energy consumption…averages less than 5 GJ/capita…can guarantee even basic necessities to all its inhabitants” (p. 358). At 40 – 50 GJ per capita, “Some societies have been able to secure adequate diets, basic health care and schooling, and a decent quality of life” (p. 362). Current quality of life peaks at about 110 GJ per capita per year. Beyond that, no discernable improvements appear.
The most positive long-term scenario would be solar-powered energy for all human needs. Our Sun produces 3.9 × 1026 Watts of energy per second. That is roughly 30 trillion times more than our total use of fuels (fossil and biomass) and primary (hydro and nuclear) electricity in 2005. For as long as our biosphere remains viable, we will not run out of solar energy.
The ultimate scenario is one in which humans realign with the biosphere – if that is possible. It will make no difference how much energy we generate, with or without GHGs, if we make the planet less habitable for all species. We cannot continue to extract resources which took millions of years to create, and then dispose of wastes with no way for them to degrade and regenerate in the natural cycles that exist.
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