The bathtub is full!
Imagine with me a bathtub. A big, old, clawfoot bathtub. The tap is on and the drain is also open. However, the water coming into the tub is greater than what is flowing out of the drain. So, naturally, the bathtub is filling up. At the same time, the tap has continued to be opened more and more, so the difference between what is coming in and what is going out is increasing.
Since this is a big tub, there has been room to keep all the water. But now, the tub is very full and close to overflowing. What can be done?
Shift this analogy to the climate. Our emissions of greenhouse gases has been greater than what the climate can capture. The tap is open further than what the drain takes out. There are also other places which can ‘capture’ these greenhouse gases – these are called ’sinks’ by climatologists. This is the bathtub and it had a lot of room.
There is evidence that these ’sinks’ are filling up. The bathtub is full. What we need to remember, is that in order to get the level of the bathtub away from the edge where it will overflow, we need to have the tap’s flow to be less than what out the drain.
Which means our level of greenhouse gas emissions needs to be more than just stabilized. We’ll still overflow if all that countries around the world do is no longer increase their emissions. We need to lower the total emissions around the world so that we are emitting less than what the climate can ‘absorb’. This way, the bathtub will slowly start to drain.
There is more and more technology which will allow us to change the way we live or the way we produce products so that we do not emit as many greenhouse gases. These are already available for us to use. We just need to make these changes in our practice. And hopefully the image of the bathtub helps us to understand why!
Sterman from MIT talks much more about this bathtub and what we can do.