US credit ratings agency Standard & Poor’s has ranked Cambodia’s economy and creditworthiness as the most vulnerable to the effects of climate change.

Of 116 nations measured by S&P as part of a vulnerability index published last month – with a number 1 ranking being the least vulnerable – Cambodia scored the lowest, coming in at 116th.

The index took into account the share of Cambodia’s population living in areas below five metres of altitude, the percentage that agriculture contributes to GDP and the results of a similar study conducted by Notre Dame University in 2012.

Cambodia’s dependence on agriculture-related products as a driver for 35 per cent of its GDP growth in 2012, the more than 10 per cent of the country living at or below five metres of altitude, and a poor ranking in the Notre Dame University study all contributed to the country’s “highly vulnerable” status.

“[Cambodia has] the highest average rank number of any of the rated sovereigns included. Therefore, we assign Cambodia the highest possible overall rank of 116, being the most vulnerable to climate change,” the report states.

“Climate change, and specifically global warming, is going to be the second global mega-trend affecting sovereign credit risk,” it says, cautioning that the world’s poorest nations’ economies are set to be disproportionately affected by global warming.

Food insecurity, reduced agricultural crop yields and restricted labour forces triggered by changing rainfall conditions, disaster recovery efforts placing increased pressure on government budgets, and civilian deaths are just some of the economic consequences Cambodia faces as global warming worsens, the S&P report warns.

Vietnam, Bangladesh and Senegal followed Cambodia as the economies most at risk of climate change, while Luxembourg, Switzerland and Austria – all high-altitude European nations – were ranked as the least vulnerable.

S&P affirmed Cambodia’s credit rating of “B” in 2013, labelling the country as having a strong and stable long-term and short-term outlook. The ratings agency did not cite climate change risks as a detrimental factor in its latest credit rating.

Sok Puthyvuth, president of the Cambodia Rice Federation, said that the economic impact of climate change was a global issue and that Cambodia’s agriculture sector should look offshore for solutions to the threat.

“I believe the solution to this will rest in technologies which allow farmers to respond quicker to changes in the weather,” he said, citing examples from Israel where farmers are able to grow their crops even in harsh desert environments.

Srey Chanthy, an independent economist, said while the threat is not immediate, the Cambodian government needs to start investing in disaster-mitigation measures sooner rather than later.

“I am concerned for five years down the track,” Chanthy said. “The government needs to invest in disaster-resilient infrastructure such as water irrigation and drought resistant varieties, while somehow also maintaining the existing natural resources.”

He added that Cambodia’s economy would find it difficult to recover from a natural disaster much worse than the floods of 2011, which damaged 10 per cent of the country’s total agricultural crops and $200 million worth of infrastructure.

“Cambodia in 2011 had to have financial intervention from donors such as the Asian Development Bank and the World Bank to recover from the floods,” he said.

“If much worse than that occurred it would be very difficult for the economy to recuperate.”