They help counteract the uneven distribution of solar radiation reaching Earths surface so if there was no surface current Earths surface temperature would increase to dangerous levels over time.
Answer: sensory adaptation.
Sensory adaptation it's when the sensitivity to a
stimulus decreases as a consequence of constant exposure to the stimulus.
When the stimulus starts, the neurons will begin firing action potentials. After a while in the same environment, you'll most likely have forgotten all about that sensation (in this case noise) even though the stimulus is exactly the same.
A president can know their 2 year term is up when other politicians are considering to prepare their own campaigns for the next election cycle. It always occurs in the midst of their term, usually two years in.
