There have been warning signs for decades; now South Africa’s second-biggest city is racing to prevent a drought from throttling the economy and causing social unrest.

“Just as the apostles faced the storm on the sea, you had to face the brunt of ‘El Niño costero.’”

Many readers also pointed out that in comparison with other foreign policy issues, climate change’s consequences are the broadest and have the most impact.

“What we need to do is just continue to live out the challenge of ‘Laudato Si’,’ which is to examine our relationship with the earth, with God and with each other to see how we can become better stewards of this gift of the earth.”

The pope said the Paris agreement is "a clear path of transition toward a model of low- or no-carbon economic development, encouraging solidarity and emphasizing the strong links that exist between fighting climate change and fighting poverty."

Scientists say new figures show global carbon emissions will reach a record high in 2017.