TLDR We cannot.
Climate - truthful information about climate, related activism and politics.
Discussion of climate, how it is changing, activism around that, the politics, and the energy systems change we need in order to stabilize things.
As a starting point, the burning of fossil fuels, and to a lesser extent deforestation and release of methane are responsible for the warming in recent decades:

How much each change to the atmosphere has warmed the world:

Recommended actions to cut greenhouse gas emissions in the near future:

Anti-science, inactivism, and unsupported conspiracy theories are not ok here.
Slightly longer tl;dr: "Pay me or other influencers to attend a conference where we can muse about whether we truly cannot"
That's how imagination works. You can imagine something having nothing to do with reality.
Maybe I don't understand the question.
We got here not by one big move. It took a long time, poor information and many small choices. Companies made money by convincing people to be unthinking consumers.
On macro scale, you cannot do much except be informed and vote. If everybody bought green, corporations would have to follow the consumer's spending habits to make profits.
On a personal level, you can grow a garden, plant edible landscape and edible perennials wherever you can. You can buy the most efficient and durable cars, appliances and clothes. If possible, you can choose live in areas that do not depend on massive use of energy for heating or cooling.
"Positivity" is a weird thing. You can be rich and sad because your neighbor is more rich. You can be working yourself ragged and happy because it's a competition on a topic that you love.
You can be Caribbean pirates dancing with death fighting for life and liberty against cartoonishly evil empires and you can be suffering from depression in safety with people you love.
You can live in the shadow of a toxic chemical plant treasuring every moment you spend with your family or you can have a private island and prosperous family and feel hollow.
Climate change will almost certainly lead to violent clashes between groups and states unwilling to give up unsustainable wealth and privilege and also between them and people just trying to survive, on a scale never before seen on Earth. Nuclear, biological, and mass autonomous weapons may be used. Over a billion violent deaths next century seems likely, and over seven billion violent deaths is very possible.
But that doesn't mean we have to feel negative all the time while living through that. That depends on what we do and what we're working for. Building anarchist spaces, I haven't felt this alive since I was a child. People are facing the risk of permanent injury, prison, and worse, but they look more alive than 99% of wage workers.
We have a chance to build a better world with our own hands as the old one burns, for however many millions of people will be alive in the 22nd century if not for ourselves. Every thing we do matters to us, to our friends, to our comrades, and to the world. Maybe we'll end up in a place where despair is appropriate, but it is not now.
I don't know if this counts as a "positive imagined future", but it is the one we are heading towards and I am happy.