On the other hand, it seems quite logical that one needs to tap into the heat capacity of these deeper layers to create internal variability on long time scales. (gfdl.noaa.gov)
This places recent global warming trends in the context of temperature changes over longer time scales. (skepticalscience.com)
Where my concern does lie however, is within not knowing the «forces of nature that act on very long time scale». (universetoday.com)