The caesium finds its way into tiny pores on the surface, and the only way to remove it effectively is to grind off the surface, a difficult procedure which can create contaminated dust.

BBC: Daunting challenge of Fukushima clean-up

The most recent spikes in the Earth's temperature are no different, long term, than the peaks one finds beside deep valleys on the Earth's surface.

FORBES: Fact and Comment

It travels around the room and its carpet-covered surface bumps into objects that come into its path, until it finds a resting place.

CNN: Clever clock stops you sleeping late