Global average temperature has risen by about 1oC over the last century. But it has not risen steadily. There have been ups and downs. The record is noisy. When the data is analysed its variance spectrum is “red”, i.e. there is a concentration of variance at low frequencies. This gives rise to “spurious regression” which is sufficient to account for the observed variation, that is, there is no statistically significant trend in global average temperature. The presumed correlation with atmospheric CO2 concentration is also spurious for the same reason.
In 1962 philosopher Karl Popper set out seven principles defining the Scientific Method, e.g. A theory which is not refutable by any conceivable event is non-scientific. Climate models are certainly refutable and so are indeed scientific theories. Prof John Christy of the University of Alabama has spent decades collating model predictions of global average temperature and testing them against observations. All but one of 102 models failed the test. Clearly the models don’t work. They don’t work because the equations on which they are based do not satisfy the Second Law of Thermodynamics. If climate “science” really were a science this sort of fluid dynamic modelling would have been abandoned decades ago.
Instead millions of dollars in research funding is being wasted on projects that are no better than Astrology.