These are installed/operating reactors with a cooling design as old as their nuclear technology, whose designers made assumptions about what future water temper

These are installed/operating reactors with a cooling design as old as their nuclear technology, whose designers made assumptions about what future water temperatures would be in the locations they were built. Those assumptions turned out to not be valid... it's not unusual for that to happen in engineering designs for systems with a lifetime that spans decades. The article implies that nuclear power isn't an option to reduce carbon footprint because nuclear reactors won't work with elevated water temperatures. This is false, and is probably an attempt at influencing public opinion away from nuclear energy. All that's really happening is that existing reactors aren't getting the cooling capacity they need from their existing water cooling plant. This can be addressed by expanding the cooling system or building a new one with greater capacity. Expensive, and undesirable to have to do, but that's very different from "Nukes can't work because of climate change" Newly built reactors would simply take into account the elevated external temperatures from climate change and be designed according to those constraints in the first place. The core of modern reactor designs is fueled by molten salts which also function as a coolant at temperatures of 900F or higher. As long as the cooling water that removes waste heat is cool enough in ambient temperatures to not be already boiling, a cooling system that uses it can be designed.