The Frame and Scale of the Climate/Energy Challenge: Issues and Implications (18 Dec 2007)

AMS Climate Change Audio - Environmental Science Seminar Series (ESSS)

Does the current framing and scaling of the climate/energy issue adequately capture the challenge posed? If not, what might be a more appropriate frame and scale? The Union of Energy and Climate The issues of global energy demand and climate response are, at one level, complex and contentious. However, they are linked by simple but compelling considerations. First, we know that energy demand is driven by the product of population, per capita yearly income, and the amount of energy required for each dollar of economic production. The product of these three quantities sets the rate of current (2007) world energy consumption at approximately 0.5 billion trillion joules of energy each year. With the projected increase in population and average per capita income, this number will reach approximately 1.5 billion trillion joules each year by 2050. That increase is equivalent to the construction of 1000 large coal burning power plants per year for the next four decades. The scale, the size, of this increased demand for energy must be recognized in any analysis of the global climate issue because approximately 80 percent of current energy generation is from fossil fuels that release carbon dioxide when combusted. While the flow of energy is obviously important to the global economic infrastructure, the flow of energy within the Earth’s climate system reveals simple but compelling conclusions. The Earth’s climate system receives approximately 4000 billion trillion joules of energy each year from the sun in the visible region of the spectrum. The Earth radiates approximately 4000 billion trillion joules of energy back into the blackness of space each year in the infrared. But the energy flow within the climate system is such that some 5500 billion trillion joules cycle per year between the Earth’s surface and the atmosphere that contains water vapor, clouds, and carbon dioxide, etc. The amount of energy cycled back to the Earth’s surface from the overlying atmosphere increases with increasing carbon dioxide and water vapor. Why is this important to the issue of climate change? Small changes in globally averaged land surface or ocean temperatures are often cited and debated, or their significance casually dismissed. That is the global warming debate. That discussion misses the crucial point. It is the net flow of heat, not globally averaged temperatures, that guides the course of future events. Net heat flow carries with it a fundamentally different message from the implications of global warming. An analysis of the climate issue from this point of view will be topic discussed at this AMS Science Series.