Monday, 24 June 2013

All Weather is Attributable to Climate Change

Imagine for a moment that you are driving on Highway 401 doing the speed limit at 100 km/hr. Traffic is moving along and other cars are moving along with you with minor differences in speed, say from 90-110 km/hr. You are in a normal traffic flow that's fairly predictable, allowing you to maintain a nice comfortable cruising speed. A car blows by doing 140 km/hr, weaving through traffic, disrupting traffic and risking an accident as other drivers brake suddenly when he cuts in front of them. Further along traffic all of a sudden bunches up, brake lights flash everywhere, and it's because someone is putting along at 60 km/hr, again disrupting traffic and risking an accident. The drivers doing 140 and 60 km/hr are driving at abnormal speeds that disrupt the normal traffic flow making the other drivers uncomfortable and incurring their ire.

Why is 100 km/hr considered "normal"? Because of an arbitrarily posted speed limit that everyone agrees to adhere to. On other highways and in other jurisdictions the speed limits vary, setting a different standard for normal. But consider what is happening as everyone drives at normal (or abnormal speed). When you press the throttle, you cause fuel to flow to the engine. You are causing an input of energy. You control how much energy is input into the system, but you are still inputting energy. The normal state for your vehicle (when turned on) is when the engine is idling. There is no "normal" amount of energy that you input. Everything above idle is variable and subject to the decisions you make. On various roads the amount of energy required to maintain the posted normal speed varies appropriately.

It is much the same with our climate. The amount of CO2, methane and other labelled green house gasses in the atmosphere are the throttle that control how much solar energy is trapped and inputted into our climate. An ideal system, where the throttle is kept at an even setting, can process and remove excess CO2 keeping things more or less in balance. Human activity is disrupting this balance by causing the throttle to be increasingly depressed, continuously increasing the energy input into the system and accelerating the warming process.

As a result of this acceleration, worldwide climates have changed and are continuing to change. Since climate patterns drive weather patterns, it is fair to say that all weather is affected by this higher energy climate system.

We like to think of weather as normal and abnormal. Even worse we use descriptions of "natural" and "unnatural" to describe weather events. And then we pick and choose and say the "unnatural" weather is caused by climate change while natural weather is caused by.. well.. we don't say what it's caused by. It is assumed that climate change doesn't affect "natural" weather events. But if the climate has changed, how is "natural" weather unaffected? Just as we use the arbitrary 100 km/hr speed limit as a definition of a normal speed on the 401, we use weather that we like as the arbitrary marker for normal weather and blame "climate change" for abnormal weather events. But the climate still dictates the weather patterns we experience. Every weather pattern, including the ones we like and the ones we don't.

No single weather event is linked to climate change. All weather events; the nice, the good, the uncomfortable and the damaging are linked to climate change. What has changed is their normal distribution, i.e. the occurrence of each type of weather event in any given region.

It has become a fallacious and distracting argument to try to link weather disasters to climate change. Focusing only on the worst weather events implies that these disasters would never have happened if climate change wasn't happening. That is illogical. Floods, hurricanes, ice storms, tornadoes, droughts and other nasty weather patterns happened before we humans changed Earth's climate and would continue to happen if we had evolved as Gaia loving druids in perfect harmony with nature.

So were the recent floods in Calgary affected by our changed climate? Absolutely. Just as the nice day we had here in Ontario that allowed me to type this blog post in comfort on my deck was affected by Climate Change.

Our climate is changing. New weather patterns are emerging, and the changes we have wrought could be disastrous for societies that depended on the old weather patterns. And for me, that is frightening enough. Changes that we are not prepared for will catch us with our pants down and cause damage to our food supply, our homes and our infrastructure. And we ignore at our peril the impacts of weather that we like. Early warm springs and light winters can negatively affect us too. Harsh winters that used to kill off insects that damage our crops no longer prevent their spread as they move into new territories. Drier springs and early spring melt affect our growing seasons by contributing to drought like conditions in our fields and farms. It isn't just the big headline grabbing events we have to adapt to, it's the subtle long-term changes that affect us too.

All weather is affected by climate change. And all of us are affected by those changes. We're being forced to adapt, whether we want to or not.


Kuze said...

Great piece.

I find the usual crowd of Malthusian bed-wetters' argument that warming is uniformly bad for humanity unconvincing. Especially when they act as though we're barely hanging on through the past century's warming.

Looks pretty good to me. There is a false schism present in much environmental discourse as though "humanity" and "nature" are two different things. Whether something is "natural" is irrelevant, the question is whether something is of net benefit or net harm.

Ken Breadner said...

Excellent analogy.
I'd note that the 'norms' are slowly changing. I don't know if you've noticed, but the night-time lows are considerably warmer than they used to be, most of the time now. You used to be able to ballpark a low as half the high temperature. Now that's out the window.