"Sea-level rise in this century is likely to be 70–120 centimeters by 2100 if greenhouse-gas emissions are not mitigated." Source: Potsdam Institute for Climate Impact ResearchAs most who know me are well aware, I'm a skeptic when it comes to claims made by global warming alarmists. In fact, I refuse to convert to calling them "climate change" alarmist because that phrase has no quantitative meaning. Climates always change and there is no single climate change theory as I've mentioned in one of my previous posts. There are at least 7 different theories on why the Earth's climate changes.
That being said, one of the predictions that have always bothered me is sea-level rise. Why? Because in order to predict sea-level rise you have to first calculate sea-level which is extraordinarily difficult. The field of study wherein sea-level is estimated is called geodesy or geodetics. There is an excellent (and very brief) YouTube video describing the immense complexities of calculating the Earth's sea-level.
As the video says, "Sea-level seems like a pretty easy concept, right? You just measure the average level of the oceans and that's that." However, there are a large number of variables to consider. I won't go into the details here. What's important is the accuracy of those estimates provided by geodetics. As the video states, "The model has allowed Geodesists themselves to correctly predict the average level of the ocean to within a meter everywhere on earth." In mathematics, this concept is called statistical significance. It means that measurements less than this statistical significance have a higher probablity of being due to just chance alone or random fluctuations in the calculation process. So, if the statistically significant sea-level measurement is approximately 1 meter, how can a climate impact study make a prediction that both varies below that measure (i.e., a variance of 50 centimeters ) and whose predicted increase is only 20 centimeters above the statistically significant measurement?
The answer is that it can't! It's like having a meter stick with no markings on it and measuring an object as being 70 centimeters. That my friends is what we call a SWAG (scientific wild-ass guess.) Factoring in this concept, let's rewrite the opening quote to adjust for mathematics and favor the alarmists.
"Sea-level rise in this century is likely to be 0-2 meters by 2100 if greenhouse-gas emissions are not mitigated."Doesn't sound so precise or scientific anymore, does it. This implies that there could be no impact or high impact. That's the point and they are hoping no one notices!