There are good reasons for Putin to fear climate change.
Warmer weather causes permafrost to thaw, which has several unpleasant consequences.
When it melts, turbo-anthrax spores from 20.000 years ago reactivate; then the water dries off and the (infected) dust gets swept away by the winds. There have already been outbreaks caused by ancient anthrax.
Then the methane trapped in the muddy ice percolates upwards and enters the atmosphere: methane is four times as potent as CO2 at greenhouse effect; furthermore, it breaks down into more CO2 (and water vapour). Lastly, the decaying plant bits start rotting again as microbes gain purchase, producing even more fresh methane. Oh, and did I mention that the methane might catch fire?
And then there are the summertime forest fires. Since Russia is so vast, forest fires can quickly spread over thousands of hectares. A single year of heavy forest fires caused problems to Russia's food supply. Now imagine them as a yearly event.