Dramatic swings between extreme heat and intense rainfall are testing China's ability to cope with increasingly wild weather, as high temperatures challenge power grids and water security while floods ruin crops and threaten urban populations.

Officials have warned repeatedly that China is especially vulnerable to the impacts of climate change due to its large population and unevenly distributed water supplies, even as infrastructure is built and policies are rolled out to bolster the country's climate resilience.

How worrying is the heat?