Why aren't we talking about this?

FYI:  This is a break from your regularly scheduled homestead building programming.

I recently watched this clip from Bill Maer’s show where world renowned climate scientist Bill McKibbon had a short debate with 2 conservative commentators about whether climate change is real and warrants immediate action.  In it, Bill McKibbon asks if the actions to mitigate or reverse climate change are conservationist in nature (i.e. trying to maintain the current state), why isn’t it a conservative political issue?  I would encourage you to watch it (its short) before reading the rest of this so that you have the context for what I’m about to say.

http://www.liveleak.com/view?i=ce7_1349566635

In the clip, a conservative writer for CNN makes the argument that “The projections for how bad it will be go out for 100 years and no model can be accurate that far in the future”.  He also seems to imply that we should just wait and see before we commit to doing anything about the problem.

This argument amounts to saying “We don’t know for sure so we should just ignore it.”  I have 2 counter arguments to this one.  First, there is a scientific process for evaluating how accurate a model is and one must follow it to determine how trustworthy the projections are.  You can’t just make a blanket statement that all models that try to project into the future are inherently wrong.  That would mean that all budget projections for federal and state governments should be tossed out, all retirement planning is a waste of time because it depends on projections of the economy out 40+ years and no one should ever be granted a 30 year mortgage because it requires believe the model that our economy will grow thus ensuring that you continue to have a job to pay it back.  Clearly, we use models at all levels of our society and they serve a useful function to alert us to trends and help inform decisions about how our current behavior can influence future results.  The same is true for climate models.

The scientific method for evaluating a model uses shorter term predictions to test whether the model accurately represents a system’s behavior.  Typically, a scientist would put in the values for the system at some known point in time (so, say the climate and human activity for 1990) and let the model run to see how well or poorly it predicts the current state.  Additionally, a given run of the model using current data would be checked against as we move forward to see if it accurately represented how the system is behaving now.  If the model performs well in those tests, then its results can be assumed equally trustworthy in the longer term.  No model is 100%, but many are close and they provide necessary information on how our decisions can affect the future.

Along with the accuracy check, a scientist would look at the bias in the model.  No model is 100% accurate, so an analysis of the gaps between what the model predicted and what actually happened gives  a sense of whether the predictions generally err on one side or the other of true – in other words, is the model generally predicting a worse situation or a better one?  Future predictions can then be evaluated in that light.

Lets take a look at how climate models perform under this process.  First, there are many climate models out there.  Every major national energy agency has a model and there are numerous models in academia.  All of the commonly used models show a significant warming trend that leads to increasing natural disasters, more frequent and severe droughts and significantly rising sea levels.  Lets look at one of the oldest of these models, the one presented in The Limits to Growth published in 1972.  In this book, a group of scientists predicted that human populations would collapse somewhere around 2050 without significant, large scale and unified action.  Scientists have compared actual conditions in the world with the model's predictions at several points, including a printed update in 2004 (Limits to Growth: The 30-Year Update)  demonstrating that we are tracking very closely to that prediction now.  We are right on the path predicted by the model when no actions are taken to improve the situation.  Based on that, we can have a high degree of confidence in the model’s future predictions, none of which are pleasant. 

Now lets consider the second test – which way are the results biased?  This model, along with the ones used by the major energy agencies, has a bias toward optimism.  What does that mean?  It means that the predictions are proving to be better than what is actually happening.  The current effects of climate change are more severe than what is predicted by most models.  This means that when we see the model predicting it to be really bad in the future if we don’t do something, it will probably be worse in reality.   

So, the models used to predict the effects of climate change have proven very accurate and their bias is toward showing things will be better than they are actually proving to be. 

My second argument for why we should not just throw out all scientific models that predict the future (other than that it is a ridiculous idea on its face), is that his argument amounts to saying, “lets gamble and see if its really as bad as you think it will be.”  This is akin to saying that we are collectively ok with gambling the lives of over 6 BILLION people because we don’t want to change our policy and behavior.  Why do I say we’re gambling with people’s lives?  Lets look at some of the concrete effects of climate change, most of which we can already see.

First, we know that we can grow enough food to feed the current world population in the climate we have enjoyed for the last several centuries.  As that climate changes, there is no guarantee that we will be able to continue to do that.  In fact, there is mounting evidence that we will not be able to feed the world in the near future.  The overall drying and warming trend mean that the kind of farming we use today to feed ourselves can’t produce as much food as it does now.  More specifically, it says that every 1 degree increase in the average global temperature results in a 10% reduction in the amount of grain harvested.  We are already predicted (and remember the predictions are biased toward understating effects) to see a 2-4 degree rise in global temperatures.  That means a 20-40% reduction in our staple crop production.  This in a world that is already seeing record levels of hunger (we hit an all time record for number of people starving in the world last year).  Its safe to say that a reduction of that magnitude would result in widespread famine because it already is (we’re already 1 degree higher than our 1900’s average).

But wait, if it gets warmer doesn’t that mean we can just move farther north and farm there?  As one who has spent a lot of time growing food, I love this line of reasoning.  It clearly comes from people who have no basic understanding of geography or farming.  If you look at the world’s major food producing areas (like the American Midwest), they share one common thread – great soil.  In order to consistently farm somewhere, you need deep, loose soil that will feed the plants.  Now lets look at what is directly north of the Midwest.  Hmmm.  Canadian forest.  Well, we can just cut the trees down, right?  Not exactly.  Those trees are growing on rocks.  The soil in the area of Canada that will have weather most similar to the current Midwest is shallow and full of rocks.  This is not an area that can be successfully farmed on a large scale.  Additionally, if we cut down all the trees we will further accelerate the warming trend and all of its effects.  So, no, we can’t just move our farms north. 

Second, the increasing frequency and severity of natural disasters means that more people will be killed, displaced and traumatized by tornadoes, floods, droughts, hurricanes, mud slides, etc.  It will also be more expensive to pay for more and worse storm damage.  Anyone who thinks that we can pay for these exponentially increasing costs hasn’t been paying attention to the current debate about the federal deficit.  The magnitude of natural disasters that we can expect to see, not in 100 years, but in 10, 20 or 30 years (so well within my lifetime) is projected to overwhelm the GDP of all developed nations.  In other words, we won’t be able to rebuild.  Those affected will be left with nothing.  The suffering and trauma this will cause are unimaginable and they will happen everywhere.  We are already seeing this in New Orleans where many communities still have not been rebuilt since Katrina.

To summarize my argument against the “models aren’t accurate and we should ignore them” point:

-The models have proven very accurate in the 10-40 year window that we already have data on.

-The models are biased toward things being better than they are turning out to be, so if they say its going to be bad we can assume it will be worse.

-We will not be able to feed ourselves in the world predicted by climate models

-Increasing numbers of people are and will be affected by natural disasters that we are less and less able to deal with.

One last thought in case you aren’t convinced:  you don’t need the model anyway, because its already happening. All of these effects are already starting and are easy to see.  Climate change isn’t the future’s problem, its ours.  Right now.  Here.  And its getting worse.  This is THE ISSUE we should be talking about.  And we are ignoring it.