Question: What countries are most vulnerable to climate change and why?

Hazel Jeffery answered on 8 Feb 2021:

The World Economic Forum used an index from the Notre Dame University and it showed the most vulnerable countries to climate change as the following:

So what is it that makes these countries so vulnerable?
Somalia: Both food and water supplies are likely to be hit, with changing weather patterns causing drought and famine.
Eritrea: Food supply problems, already common, are likely to be made worse.
Sudan: Existing problems with access to clean and safe drinking will be made worse, with the related risk to human health.
Burundi: Reliance on rice, wheat and maize means changing weather patterns are a threat to food supply.
Papua New Guinea: Rising sea levels threatening food, water and infrastructure.
Mauritania: Combination of drought and rising sea levels threatening aspects of food and water supply, as well as damaging infrastructure.
Yemen: Worsening of existing water supply problems, and increasing levels of poverty.
Chad: Both drought and flooding are likely to cause problems for farmers in the country.
The Solomon Islands: Rising sea levels are already threatening the Islands’ entire existence.
The Gambia: The agriculture sector could be hit hard by changing weather patterns.

There are different ways of creating this vulnerability list depending on what factors you think are important.