Long before people started measuring CO2 concentrations in ice cores we knew, unequivocally that the climate on the planet "changes." It has been both warmer and colder in the past, there are fossil records, there are glacial valleys, there are even pictures painted on cave walls.
Some scientist asked the question "Since we know climate changes, is it changing now? And if it is changing now, how is it changing?" And in response to that question lots of great research was done to look at factors which could affect climate.
Generally the science has always started with a basic model describing net energy, energy added to the planet minus energy radiated from the planet. The theory being that the laws of thermodynamics tell us that if the net energy was positive the overall planet would get warmer over time and if the net energy were negative it would get cooler over time.
Once that was established as the basic framework, people set out to try to identify every way in which energy is 'added' to the planet (sources) and every way in which energy 'leaves' the planet (sinks). Each of these sources or sinks have an unknown contribution to the overall equation.
Many of the sources and sinks are variable, which is to say they change in magnitude over time. So a sub-problem that people have invested a lot of time and energy in trying to identify 'proxies' or direct ways to identify variability. The classic example is of course CO2.
CO2 is a 'greenhouse' gas in that it traps energy because it is opaque to infra-red light. Higher frequency light passes through it and is absorbed or reflected by what that light hits. Light that is reflected returns to space, light that is absorbed is re-radiated as infra-red light (black body radiation). CO2 in the atmosphere prevents that radiation from leaving the planet. So like a car with the windows up, or a green house, the infra-red light is ‘trapped.’ The amount of infrared light that will be trapped (and its energy content) is proportional to the concentration of CO2 in the atmosphere. More CO2, more energy is trapped, less goes to space.
Once you have a bunch of sources and sinks, and measurements of their variability over time, and measurements of the temperature over time, you construct a 'model' for how they all contribute to the climate. The model is a series of coefficients to attach to each source or sink based on its relative contribution to the other sources and sinks.
You pick numbers kind of out of the air as to the co-efficients to give each source or sink, and you use the measurements you've taken and put them in your model and get back a predicted set of temperatures. You compare that to the temperatures that were actually measured and look to see how well they correlate.
You continue to measure these things, you feed your new measurements into your model, and you predict future changes. Then when the future becomes the present, you look at what you predicted and compare that to what the model said would happen and if they don't agree you go back and fiddle with the co-efficients until they do.
That is all good solid science. But in climate science something unfortunate happened.
Of all the things folks were putting into the models, the one that had the biggest co-efficient (which defined it as the greatest overall contributor to the climate) has been 'greenhouse gases' (which includes CO2 and Methane). Scientists being scientists identify all the sources of greenhouse gases in the atmosphere. And one of them, CO2, is a byproduct of 'industrialization' (aka human activity).
That observation, created a religion. The religion's first principles were:
) The climate is changing. (remember this)
1) Greenhouse Gas is the biggest factor affecting the climate.
2) CO2 is a greenhouse gas.
3) Human activity creates CO2.
4) Human activity is the* dominant factor in the warming of the climate.
5) If Humans would apply themselves to eliminating the production of CO2 the climate will stop changing.
The first tragedy here is that science didn't "discover" the climate was changing, they knew the climate changed, they were only trying to figure out if the current change was a warmer period or a colder period. That green house gases was the dominant factor was a surprise because it creates a new question “What are all the factors that change the concentration of greenhouse gases in the atmosphere?” One of the things the science agreed on was that the climate changes whether or not humans are present, so the religious tenet that we can control the climate by eliminating our production of CO2 is false.
Several people did however recognize that the religion met the model for enacting large scale changes. That model is :
1) Find a really big threat, explain how the threat will kill you.
2) Describe how only by following the religion can the threat be averted/met.
3) Explain that people who aren’t part of the religion aren’t just stupid, they are threatening our ability to meet the threat and should be eliminated/marginalized.
This scheme works and so people use it. Whether you’re un-american for not agreeing that Communisim will destroy life as we know it, or that your un-american for not reducing your carbon footprint and averting the coming flood of rising seawater, if you’re not fighting with us against the boogeyman, you are the Enemy.
So the science of climate change is still working on their models. This solar minimum will give us new data to update our models and co-efficients. If it exposes the Global Warming religion for what it is, then I don’t think Al Gore will take the fall, I think science will, and that makes me sad.