There are lot of blind spots in this single author paper: - Author does PCA to build a model however there is no data on fitness of the model. Specifically, wh

There are lot of blind spots in this single author paper: - Author does PCA to build a model however there is no data on fitness of the model. Specifically, what is the variance? Without this information it is irresponsible to make prediction to the year. - According to Wikipedia, it is highly controversial to associate Maunder Minimum to "little ice age". Author provides no details/limitations on this. Overall, it looks like more investogation needed. It would be hard to take this paper at its face value.