So what are you arguing? That it is not possible to come to any conclusion regarding the earth climate without first waiting some multiple of 400k years? That it&#x27;s not possible to separate a long-term 400k-year temperature variation trend from short term temperature variations due to unusual&#x2F;novel forcing conditions?<p>The thing your hot summer day analysis is missing is a clear physical explanation that explains why the trend you are observing is occurring, and why it is going to keep occurring until 24:00. We probably don&#x27;t even need the explanation to be 100% accurate for this to be useful, merely accurate to a first or second order approximation.<p>I believe &quot;we&quot; [1] have got enough understanding of the earth system to make some pretty reasonable inferences on limited data. Certainly not complete understanding, but it&#x27;s not like a bunch of people are merely using e.g. some deep learning voodoo to perform regression on climate data and have literally no idea what the underlying physical processes involved might be.<p>Here&#x27;s an example of my own: consider the geoengineering &quot;launch a bunch of disk-shaped satellites to block x% of the sun&#x27;s light from hitting the earth&quot; thing. Let&#x27;s ignore the fact that this isn&#x27;t necessarily a great idea, and assume someone has gone ahead and done it. We can predict with reasonable confidence what the primary consequences of this intervention will be: less light from the sun hits the planet, planet&#x27;s mean temperature lowers a bit. This behaviour won&#x27;t be at all explainable as part of a 400k year planetary periodicity.<p>[1] not in the sense of you or i, necessarily, but the relevant scientists in the field.