I’ve been working for Greenpeace for nearly three years now as a climate and energy campaigner, and I’ve been lucky enough to spend some time on the Esperanza (one of the Greenpeace ships) before. That was over a year ago, and while I remember parts of it like it was yesterday, mostly it’s a hazy but good memory, which inspired me at the time. We were lucky enough to see sperm whales on that trip, but we were far from Africa, far from home.

This time is completely different: I’m sailing on the Rainbow Warrior from Cape Town to Durban, which is my home ground. I’m different too - I have more experience, and also more questions.

South Africa’s energy future is in flux, with Eskom building two of the biggest coal-fired power stations in the world (Medupi and Kusile), the government planning six new nuclear reactors and limited renewable energy uptake.

Part of my job is making sure that people know that we don’t need to invest more money in coal, and that every time people flick a light switch in South Africa, coal is burning somewhere, polluting our atmosphere, harming people’s health and using up our scarce water.

This planet is lurching closer towards runaway climate change – when all we’ll be able to do is our best to adapt to extreme droughts and floods. The reality is that within this context, South Africa’s energy choices matter. At some stage, we will no longer able to influence the tide of extreme weather brought on by climate change, only able to try to avoid being completely swept away.

With scary droughts and massive heatwaves in the USA driving global food prices; floods in China resulting in over 50 people dead; runaway wildfires in Europe and major droughts in the horn of Africa and Brazil, it seems clear that we’re heading closer to a series of irreversible tipping points. Climate change is real, we’re already living with it. Denial won’t get us anywhere.

Sometimes the scale of what we’re facing, what I’m fighting for, can be overwhelming. It’s all so big, we’re just one organisation, one team. I’m just one person – what kind of chance do we have of actually creating an Energy [R]evolution in South Africa with enough urgency to avoid a climate catastrophe?

Which brings me back to the Rainbow Warrior. Yesterday was a crazy, magical day – the kind of day that doesn’t happen very often. We’d been sailing for a couple of days, I’d been vaguely seasick, and we’d just reached the edge of the Wild Coast. And then it happened: at least five humpback whales right next to the ship, rolling and spraying and playing…almost within touching distance. The crew said that in all the years they’ve been working for Greenpeace, they’d never seen whales that close before.  We stopped the ship for over an hour while the whales frolicked, and everyone on the ship forgot about everything, except how beautiful it is to be alive.

Sometimes we need a day like I had yesterday to put things into perspective again. Yes, the scale of what we are facing is huge, unpredictable, bigger than humanity has ever faced before. Denial would be the easier option. But Greenpeace has never been an organisation to choose the easy way out. We’re prepared to do what we must for a better future.

Now I remember why I wake up and do what I do every day. It’s all linked – the choices we make have knock-on effects bigger than we can imagine, and when you combine our efforts, together we can make a difference.