Hotter than Hades

There's been a lot of speculation about whether the latest heat wave is a sign of global warming. I'm generally hesitant to infer cause and effect from such events. Climate is what we expect; weather is what we get, and the two are often miles apart. But even if the heat wave had nothing to do with climate change, it provided useful insights into life in a warming world. We usually focus on the emissions linkage with energy at the front end, but tend to be vague about potential energy costs or benefits on the other end. But when it's hotter than blazes for two weeks at a stretch, that imposes an extreme load on power supplies for cooling, as we have seen across much of the US. Our steady migration into hotter areas makes matters even worse. Anyone looking at power grid reliability and new power generation must surely be scratching their heads over how to incorporate this into their plans.

The answer is partly a function of how we picture further warming. If we see it as a broad, gradual increase in daytime highs, more or less evenly distributed around the world, then it might not be so bad. Unfortunately, that isn't the scenario most climatologists expect. Rather, they project widely varying temperature changes around the globe. With a nod to TerraBlog for highlighting it in their posting on the subject, this is illustrated in some helpful charts showing that, as a result of higher mean temperatures, greater temperature variability, or both, we could be in for a lot more hot weather than previously. A world that's a little warmer on average, but that includes more frequent and more intense heat waves would be much less comfortable for people and much less hospitable for the crops upon which we depend, even if those crops grew faster as a result of the elevated CO2 levels.

What are the implications of all this for energy demand, and will the result dampen or amplify the drivers of further climate change? I haven't seen a definitive answer, and I'm not sure one will be possible for a long time. But although the balance point between less need for heating and greater need for cooling is highly uncertain, it does foretell a shift in fuels. Today's winter heating fuels include a hefty contribution from oil, in the form of distillate heating oil and propane. By comparison, relatively little oil finds its way into the electricity used by air conditioning. That draws on a mix of nuclear, coal, and gas--and increasingly, cleaner sources such as wind and solar.

Thus, global warming ought to reduce winter demand for oil and increase summer demand for electricity and its source fuels. That makes the rapid development of a global LNG market even more essential. Whether this fuels shift gives rise to a "reinforcing loop" in global warming depends on how much of the incremental electricity will come from coal, and how much of that will be of a type that lends itself to carbon sequestration.