Global climate is the earth redistributing heat and trying to reach equilibrium, since thermal energy always moves from hot to cold the result on any large system is weather. Our weather is chemistry and physics, this physics can be mathematically modeled and has been experimentally verified, the same holds for the chemistry. The earth’s climate is a complex system, mathematical models of complex systems can never be 100% accurate, another complex system is the financial markets, with all the vast resources and effort spent trying to predict the market it has never been reliably accomplished. Sport teams cannot be 100% modeled, the worst sport team can unexpectedly defeat the best sport team. A climate model with 100% accuracy will never happen. Sporting outcomes cannot be perfectly predicted, but the potential outcomes are modeled well enough to allow sport bookies to make a good living, climate models cannot be perfectly predictable but the overall forecast can be useful.
The earth’s energy inputs are measurable physical events, there is no magic, we receive energy from the sun, from radioactive decay in the earth’s core, from gravitational flexing of the earth’s shape, from the rest of the universe via star light and cosmic rays, from natural events such as forest fires, and finally, from mankind’s activities. On an average day the sun is the dominate energy source, although a nearby super nova would certainly change that equation, of all these sources, only one can be affected by humans, and that is the human contribution. Our component has two forms, the actual energy we contribute from automobile engines and nuclear weapons test, plus the changes we make in the chemistry of the atmosphere and oceans. Changing the composition of a liquid will change its thermal response, adding antifreeze to water changes its freezing point and it boiling point. Same for a gas, changing the humidity (water content) of air changes the amount of thermal energy it can hold. Human activity adds components to our oceans and atmosphere, we add dust by walking around, we add combustion by-products and we add artificial fertilizer to our lawns. All this modifies the thermal properties of atmosphere and ocean. Too much of anything is bad, and one bad result is the increase in the thermal retention of atmosphere and ocean.
All life changes its environment, for instance, the first anaerobic microbes poisoned themselves with their waste product of free oxygen, and the roots of vegetation help grind down mountains. That humans will change our environment is natural, it is even unavoidable, where we differ is that we are aware of our actions and the possible consequences.
The general public has become aware of global climate change, while the uncertainty of a complex system makes the consequences a range of possibilities. The range of possibilities contains no positive outcomes following the current trajectory. This lack of a good outcome is why we need a public debate. The science of climate change can be weighed, tested and verified. Our policy choices to climate change also need to be weighed, tested and verified. To guide in the policy debate we need more than science, as normal humans we are too greedy and self centered for some coldly intellectual debate. We need a better economical and a moral argument. We need a positive vision of the future; we need a climate change policy where the rich get richer.
Exploitation of natural resources has always been profitable. Mining is profitable because the mine operator does not pay for all the cost, the toxic runoff from mines destroy local fisheries, which are driven out of business, the mine operator pays no cost for this by-product of their operation. Typically the larger society pays the full cost of natural resource exploitation. Unfortunately, this additional cost is hidden from the people that ultimately pay the bill. It is hidden in taxes, lost jobs, and increased health care cost. This lack of accounting for the total cost of human activities also applies to climate change. The cost to me of my morning cup of coffee is very narrowly defined.
Where we poorly model the science of climate change we really mess up modeling of the economic cost of climate change. The skeptics that mislead about the science of climate change find the economics of climate change an easy target. This is all so human, I just want to throw my hands up and go watch the next football game.
To guide global climate change policy we should change the accounting rules to include the total cost of human activities, but that is a subject for future blogs.