LOS ANGELES-Greta Thunberg is angry, and not just about climate change.

“The haters are as active as ever”, the 16-year-old Swedish climate activist posted on social media on Thursday, “going after me, my looks, my clothes, my behaviour and my differences”. Anything, she says, rather than talk about the climate crisis.

It hasn’t stopped her from campaigning. On Friday, she led another of her climate strikes, heading up a huge demonstration in Montreal, demanding international aviation does more to cut its carbon footprint.

But she is clearly very annoyed, accusing critics of “crossing every line to avert the focus” with, what she calls, lies and conspiracy theories.

Of course, the attention isn’t surprising. Over the past year, Greta Thunberg has arguably done more to galvanise global action on climate than any other single individual.

And there is no question the unnerving power of her rhetoric comes in part from the fact that she is so young.

As you may have noticed, the haters are as active as ever - going after me, my looks, my clothes, my behaviour and my differences.

A key reason her “How dare you!” message hit home so hard in the UN this week was because she seemed so jarringly out of place in the air-conditioned formality of the UN’s New York HQ.

It is unusual for young people to hold the adult world to account so forcefully and so publicly and some people clearly don’t like it. Donald Trump is one. The US president appeared to mock Thunberg this week when he tweeted that she “seems like a very happy young girl looking forward to a bright and wonderful future”.

She brushed off his sarcasm on Swedish television with a laugh, saying she “knew he was going to say something about me”.

The UK newspaper The Sun has suggested these include “energy giants and pushy celebrity parents - including a fame-hungry mum who once appeared on Eurovision”.