Whoever you listen to in the lead-up to the world climate summit in Poland, there message seems to be the same. Politicians and government officials, environmental group representatives and scientists are all spreading something like stubborn optimism.

No, they say, we are not going to back down in the fight against greenhouse gases, despite all the bad news. And anyway, a great deal has already been achieved. More and more countries are investing in renewable energies, and in Poland we are going to turn the vague promises made in Paris into concrete policies. We will do this together — poor countries and rich countries alike.

Dark shadows

If only there weren't those dark shadows looming over this COP24 climate conference: The US, under President Donald Trump, quit the Paris climate accord last year. Brazil, under its new president, Jair Bolsonaro, will probably be leaving soon too. The Amazon country's nationalist head of state has already bluntly called off holding next year's conference in the capital, Brasilia. Emissions are rising again worldwide, and the two-degree target set in Paris is far from achievable.

And not only in the US and Brazil, but also in Australia and many Eastern European countries, multilateral agreements based on the goodwill of states are not en vogue, to put it mildly. The political will needed for saving the world's climate has been better. And what about Germany? Although it is bravely sticking up for climate protection, it will not be able to meet its own climate targets for 2020 and is preparing for a heated debate on the urgently needed phase-out of lignite mining, which could take a great deal of time.

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For the time being, hope is therefore once again coming from below, at the grassroots level. In the US, for example, cities, municipalities and private companies are joining forces against the ignorance of the climate change denier-in-chief Trump.

Young people in Germany are taking to the streets for the environment again, after long years of being rather passive. And more and more people are aware of what needs to be done now, apart from restructuring the economy: a new form of mobility is already beginning to take hold in metropolises. Cars driven by combustion engines still exist, but certainly not for long. These are all wins for climate protection.

Putting on the pressure

In Germany, recent state elections and the rise of the Greens have shown that many people regard climate change as one of humankind's most pressing problems. On the other hand, right-wing populists here and abroad are using crude conspiracy theories to oppose the overwhelming scientific conviction that climate change is caused by humans.

What this actually means for the UN conference in Katowice is that more research needs to be done, money needs to be collected for poorer countries, the Paris Agreement must be vigorously defended and implemented against all odds. And we must all remain optimistic and hope that change can be brought about through the growing pressure of communities around the world.