Global warming or climate change?

These two phrases are used, misused and confused.  Time for some clarity.

They mean different things.  If you use them interchangeably to mean the same thing then you’re likely to have got it wrong at least half the time.  In fact I reckon folk get it wrong more often than not.  There’s a distinct bias towards climate change, which is somehow regarded as more politically correct, at least by those who haven’t really thought about it.

First, global warming.  There are clues in the words.  Global, because it affect the globe, the whole planet; warming because the temperature is rising.  Global warming is happening because we’ve added greenhouse gasses to the atmosphere.  It will continue happening until the planet reaches a new equilibrium temperature at which incoming and outgoing radiation are in balance.

Climate change is to do with changes in climate.  Again there are clues in the words.  Global warming will cause changes in climate and these changes are local and regional, varying depending on the geography of land and mountains, oceans and their currents.

So, if you are discussing whether a particular part of the world will get warmer or cooler, wetter or drier, more unsettled of more stable, or you are discussing resulting changes in agriculture, floods and droughts, population adaptations and migrations, then fine, use the phrase climate change.  These are all the second order consequences of global warming.

If you are discussing the effects of burning fossil fuel and of the release of methane on the planet’s climate system, then it is only right and proper to use the phrase global warming.  Don’t be embarrassed; don’t worry about upsetting people with inconvenient truths.  Call a spade a spade and call freshly dug soil freshly dug soil, but don’t muddle them up.

And another thing... think about sea level rise.  Much of it is the result of the thermal expansion of the ocean's water. Now that has to be a result of global warming, pure and simple. No climate changes involved.  Even the contribution made by ice melt is a temperature thing.  To talk about sea level rise under the heading of 'climate change' stretches language to absurdity. It's global warming.