The threat of rising sea levels within cities on the Atlantic and Gulf coasts is not lost on property owners and investors in coastal markets.

Even credit rating agency Moody’s Investors Service said cities on the coast will need to take climate change into account if they do not want to lose access to cheap credit, Bloomberg reports.

In a recent report to clients, Moody's said it now considers a city’s climate change provisions when it issues credit ratings for state and local bonds. Those markets that do not have plans in place risk default if they are hit with rising water or intense storms.

The risks are not limited to municipalities.

"The affects of climate change on commercial real estate are real and being factored in and considered by most major real estate investors and tenants today," San Rafael real estate consultancy The Muldavin Co. President Scott Muldavin said.

Topping Moody’s list of the states most at risk are Texas, Florida, Georgia and Mississippi. Others, like Miami Beach, are ahead of the game and have already implemented plans. Miami has invested approximately $500M in infrastructure projects that will prevent flood damage.

According to Muldavin, cities that do not implement appropriate climate change preparations put the commercial real estate industry at risk of facing much greater consequences than simply topping a Moody's list.

"After Katrina in 2005 and then Sandy more recently, there’s been a [massive] change in the availability of information from cities themselves on their resiliency. A real estate investor today can look up in two minutes and find copies of resiliency reports where cities identify the different parts of the city that are affected by potential changes and climate, the specific buildings affected and the potential mitigation effects," Muldavin said.

While some developers are building protective frameworks such as fences for older residences and moving electric infrastructure to higher floors to combat the risk, this means developers and landlords could still face a mass exodus of investment capital and decreasing property values should a city fail to act on a plan.

"Real estate values and decisions are based on probabilities and perceptions of things going on. So you have all the potential investors and tenants who think this might be real and then you have the perception that this could actually happen and that is something that is scary to a lot of people," Muldavin said.