Maybe we can discuss 'global warming" and leave out the Algorerhythms.

Most discussions cover the period from around 1860 to date. About 140-150 years. One reason is that the methods of measuring thempertature were primative before that time.

Here is a statement from a New Zealand scientist:

"...surface measurement at weather stations, gives an averaged mean global rise of a mere 0.6°C over 140 years, but is intermittent and irregular. Individual records are highly variable, regional, and sometimes, particularly in remote areas, show no change, or even a fall in temperature.

It is concluded that temperature measurements carried out away from human influence show no evidence of global warming.

The small and irregular rise shown by many surface stations must therefore be caused by changes in their thermal environment over long periods of time, such as better heating, larger buildings, darkening of surfaces, sealing of roads, increases in vehicles and aircraft, increased shielding from the atmosphere and deterioration of painted surfaces."