With the world’s poor predicted to bear the brunt of more frequent extreme heat and worsening coastal floods in a warmer world, aid agencies are calling on governments to direct more funding into protecting the most vulnerable communities on the front lines of climate change.

The poorest fifth of the global population is expected to experience daily heat extremes due to climate change sooner than the wealthiest, according to research published on Tuesday by an international team including Britain’s University of East Anglia.

And a report released by Christian Aid this week reveals that the Indian cities of Kolkata and Mumbai are likely to have the largest number of people in the way of coastal flooding by 2070, with Dhaka in Bangladesh, China’s Guangzhou and Ho Chi Minh City in Vietnam close behind.