The difference between Climate and Weather

 Our Climate Commission has just released a report entitled The Critical Decade. These are the key messages from the report:

1. There is no doubt that the climate is changing. The evidence is overwhelming and clear.
2. We are already seeing the social, economic and environmental impacts of a changing climate.
3. It is beyond reasonable doubt that human activities – the burning of fossil fuels and deforestation – are triggering the changes we are witnessing in the global climate.
4. This is the critical decade. Decisions we make from now to 2020 will determine the severity of climate change our children and grandchildren experience.

For the Sydney region where we live, the report predicts:

1. Higher temperatures will increase the likelihood of large and intense fires.
2. Rising sea levels will exacerbate existing vulnerability of coastal towns and infrastructure in the Illawarra/ NSW south coast region.
3. Changing rainfall patterns and the risk of more intense rainfall events pose challenges for low-lying urban centres in the Illawarra/NSW south coast.
4. Biodiversity will be at risk.

But many people, including our politicians, still confuse weather and climate. Here’s a quote from our Federal Opposition climate change spokesman Greg Hunt on the report. Incidentally he says he respects the science.

“There’s a significant issue here, although many of the claims attributed to it have not always been entirely accurate,” he said.

“The dams were predicted to be empty rather than full by now, so everybody needs a little bit of humility.”

He doesn’t understand that the full dams have nothing to do with climate. They are full because of the wet weather we’ve been experiencing over recent months in the Sydney region.

To clarify the difference between weather and climate consider these statements:

“I don’t think I’ll go on the picnic tomorrow because I think it’s going to rain.”

“I don’t think I’ll buy that seaside property as it’s likely to be a bad investment because of rising sea levels.”

The first statement is about weather and the second is about climate. Don’t let the shock-jocks and other populists confuse the issue when pointing out the cool summer we’ve just experienced or that we are enjoying a particularly pleasant autumn. Remember – this is weather, not climate.

Looking backwards, climate tells us things like how the last century compares with the previous. Looking forward, climatologists can predict what the next 50 years might be like and how it might differ from the previous fifty.

Climate forecasts should also be telling us how to prepare our communities for things like worsening bushfires, rising see levels and climate refugees.

So when listening to someone claiming climate change is not something we should worry about, always ask yourself if they really understand the difference between climate and weather.

You can read the full report of the Climate Commission here:
http://climatecommission.gov.au/topics/the-critical-decade/