The issue of whether the planet is warming due to human activity is well settled, and over the past few months, we haven't devoted much blog space to pointing out Yet Another Global Warming Confirmation every other week. Today's press release from the Earth Institute at Columbia University is worth noting in passing, however, due to its cosmic phrasing of scientific results.
The study [...] reveals that Earth's current energy imbalance is large by standards of Earth's history. The current imbalance is 0.85 watts per meter squared (W/m2) and will cause an additional warming of 0.6 degrees Celsius (1 degree Fahrenheit) by the end of this century. This is equal to a 1-watt light bulb shining over an area of one square meter or 10.76 square feet. Although seemingly small, this amount of heat affecting the entire world would make a significant impact. To put this number in perspective, an imbalance of 1 W/m2 maintained for the last 10,000 years is enough to melt ice equivalent to 1 kilometer (6/10ths of a mile) of sea level.
Of perhaps more practical interest are the details about "thermal inertia," the lag between processes that have the potential to trap more heat and the realization of that potential. This thermal inertia is caused by the slower rate at which the oceans take up and release heat.
...there is an additional global warming of about 1 degree Fahrenheit that is already "in the pipeline," and has not yet manifested in overall ambient temperatures. Even if there were no further increase of human-induced gases in the air, climate would continue to warm about that much over the next century. [...] The delayed response of thermal inertia provides an opportunity to reduce the magnitude of human-made climate change before it is fully realized, provided that actions to reduce climate forcing agents are undertaken. On the other hand, if the world decides to wait for more overwhelming evidence of climate change, thermal inertia implies that still greater climate change will be in store, which may be difficult or impossible to avoid.
This is why policy responses to global warming-induced climate disruption are difficult to craft. We face a pace disconnect between our tools -- industries and technologies -- and the problem. We're used to situations where changes to the causal factors result in visible, near-term changes in the effects. Geophysical processes don't work at that pace; improvement or worsening of greenhouse gas emissions will have no immediate consequences. Indeed, we may find that actions to cut greenhouse gases seemingly have negative results, as temperatures continue to climb. That's thermal inertia biting us in the backside, and those of us in the realm of analysis and explanation need to be prepared for the resulting public confusion.
A one watt lightbulb is a pretty bad image. Who has ever seen a one watt lightbulb?
A birthday candle makes a better image. Three birthday candles together put out about one watt. Imagine three tiny pink birthday candles burning on every square meter of the Earth's surface. Every square meter of farmland, every square meter of ocean, of forest and tundra, in every sidewalk square in every city all over the world, imagine three tiny pink candles burning day and night.
That's global warming.
Patrick, that's a terrific analogy. Powerful, immediately visible, and compelling. Thank you.
THIS JUST IN: EARTH-HUGGING CLIMATE PANICKERS HATE BIRTHDAY CANDLES. CAN BAN ON CAKES, ICE CREAM BE FAR BEHIND?