One problem with global warming is that we dont have the right words to describe it.
‘Warming’ to most of us means ‘increase in temperature’. But this is not what we really mean when we talk about global warming. What we really mean is ‘increase in energy’ (although when something experiences an increase in energy its temperature usually goes up). Most (about 95%) of the global warming energy from the sun that gets trapped here is absorbed by water in the sea.
This trapped solar energy causes the temperature of the sea to rise but not by very much; currently by 0.01° C per year. But because there is so much sea this rise requires a huge amount of energy; terajoules of it. But what is a terajoule? We dont have any vernacular words to describe large amounts of energy.
There is one phrase, however, that conjours up a lot of energy; the phrase ‘Hiroshima bomb’.
The current warming of sea surface waters, 0.01° C per year, sounds small enough to ignore with safety. But this works out at four Hiroshima bombsworth of energy every second of every day – which looks a touch more serious.
The detail is here. The IPPC stats show a global building up of heat energy of 8 x 1021 Joules per year while the Hiroshima bomb yield was 6.3 x 1013 Joules . More here.