Climate change is finally getting the publicity that it deserves and I’m over the moon about it. I’d say “better late than never”, but unfortunately that doesn’t really apply to something capable of causing our collective demise. Regardless of the current US political agenda adulterating a ubiquitous global concern about the climate, scientists are getting more of the press that they need to encourage action build upon hard facts and I am feeling a fraction more encouraged than I was at the start of this year.
As I’ve mentioned before, the reason it can be so difficult for us to act on climate change is because it often feels so out of our grasp; too difficult to wrap our heads around. With the plastic crisis, it’s easy to see that our everyday actions can have an impact: say no to the disposable stuff and switch to sustainable alternatives. But for climate change, we need to calculate our carbon footprint; things like getting rid of your car might not be a viable option for you right now. So, what can you do?
For a start, I find that educating yourself on the science can be immensely helpful. A little time figuring out how it’s all happening can fill in the blanks and help you realise the urgency required in doing something about it. So, even if you can’t get rid of your car (or fill in the blank with whatever other detrimental action you like here), you can pressure your government representatives with the facts; ask them what they’re going to do about the impending x, y or z knocking at your door. Australia’s school children just showed us all that there’s great power in peaceful protest. Plus, there’s something about seeing children as young as 5 or 6 marching for a future that society’s much older leaders can’t be bothered to protect that really hits home. We, the adults, need to do better.
The climate is fuelled by a few major powerhouses, namely those giant oceans and their changing conditions as a response to sea ice melt and sea surface temperature. As the planet gets warmer each year, we see greater melting of the ice caps, which dumps more water into the oceans. This causes a huge knock-on effect, as we’ll see, but first of all we have to understand ocean currents.
The Southern Oscillation dominates the Pacific and all of its weather. Normally at the equator, the surface waters of the west are warm and there is cool water in the east. This is maintained by and balanced with an easterly surface wind in a system known as the Walker Cell. This surface water sits above the thermocline (a special band of water that kind of acts like a wall), with very cold water below. When conditions are optimal, the Pacific sees very neutral patterns of rainfall and temperature; this is good. But some weird stuff can happen as a result of climate change and it’s becoming more extreme over time.
Firstly, there’s the La niña phase. When the wind picks up, this can drive more of that deep, cold water from below the thermocline up to the surface, resulting in much cooler water than usual in the central and eastern Pacific. For a warming climate, this is good! It reduces the risk of drought and wildfires in the United States and gives the sea a break. But unfortunately, these events are becoming less common and shorter, dominated instead by the alarming El niño reverse oscillation.
During El niño (which you might see referred to as El niño Southern Oscillation, or ENSO), the Walker Cell dramatically weakens or reverses, minimising upwelling of deep, cold ocean water and causing a warm pool of water to develop (where it is typically cooler) in the eastern Pacific. This happens when the surface sea temperature is increased, which throws off the winds and causes positive feedback, furthering the reverse oscillation.
So, why’s it so bad, you ask? Because it triggers immense flooding in South America and brings heavy rains over Indonesia, the Philippines and Malaysia. These are places often ill-equipped at dealing with the extreme weather and devestation can be overwhelming. ENSO often brings drought to areas that are typically humid, such as parts of Australia and tends to result in more intense, dramatic bursts of rainfall to these drought-stricken areas, resulting in mudslides.
Then there’s the effects on our coral reefs and the mass-bleaching events that occur during ENSO. Our seas need regular upwellings of cold water to keep corals happy, but there’s an alarming risk that these will be fewer as La Niña events become less frequent. We know that coral reefs are the nurseries of the oceans and losing them will result in a dramatic loss of biodiversity.
Another marine ecosystem that suffers are the precious and diverse kelp forests that line the west coast of North America. During ENSO, kelp-hungry urchins go a bit wild as their population booms. They can plough through a lot of kelp in a relatively short time and if there’s less kelp, there’s less habitat for everything else that lives there. Think of these urchins like the loggers of any terrestrial forest.
Finally, there are the repercussions felt around the world as a result of an El Niño event, which causes an increase in global temperature: less rainfall, more drought, more wildfires, more crop failure, more ice cap melt…it’s a self-perpetuating cycle. Remember I mentioned earlier that melting ice caps have a huge knock-on effect? Not only will the landmass below absorb more heat (furthering global warming), but there’s a loss of habitat for arctic organisms such as the charismatic polar bears and seals that need ice to survive. There is also thought to be a huge risk of disruption to our ocean currents as a result of all the fresh water ice melt being dumped into a very carefully-balanced system. Ever see The Day After Tomorrow? It was a film actually built on a fairly accurate premise and there will likely be dramatic implications for the North Atlantic if this continues.
So how do you feel now that you know a little bit more about some of the implications of climate change? I hope I’ve made you just a little uncomfortable. Not anxious, but driven to campaign for change. Your voice matters and will be heard if you use it for good, supporting your claims with facts and sharing the knowledge. The clock is ticking, so let’s get busy.