"This is in part due to their reliance on agricultural production and employment, which can be vulnerable to shifting climate patterns and extreme weather events, but also due to their weaker capacity to absorb the financial cost," S&P said. It added that this could contribute to rising global rating inequality.
Vietnam, Bangladesh and Senegal topped the list of countries most vulnerable to climate change, whereas developed nations – the United States and Europe – were at the bottom of the ranking.
Climate change in focus
The report comes at a time of increasing concern about the economic impact of climate change, as politicians, business leaders and think tanks across the word point to the rising risks and associated costs.
Read MoreLloyd's warns on climate change impact
Earlier this month, insurance market Lloyd's of London warned that insurance companies need to factor climate change, and in particular extreme weather events, into their risk models.
Meanwhile, the Organisation for Economic Co-operation and Development (OECD) said that the costs of natural and man-made disasters have more than doubled in the last ten years, rising to $1.5 trillion in damages and economic losses.
But governments have also joined the chorus of organizations cautioning on the effects of a changing climate. According to the U.S.' National Climate Assessment, the impacts of climate change are extremely wide-ranging, and include human health, weather and the environment.
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