10. New Orleans, La.
Average Annualized Loss (AAL): $1.86 billion, 18% increase from 2005

The Insurance Information Institute reported that Hurricane Katrina, which struck Louisiana in 2005, generated a record $41.1 billion in insurance losses—not including $16.1 billion in claims insured by the National Flood Insurance Program and millions more in insured damages to off-shore energy facilities.

9. Ho Chi Minh City, Vietnam
AAL: $1.95 billion, 12% increase from 2005

In a briefing on Asian flood risks, Marsh & McLennan says, "In emerging markets [such as Vietnam], companies often choose to take the risk themselves rather than buying insurance in the first place, so the issue isn't necessarily around flood insurance, it's about insurance penetration."

8. New York, N.Y.—Newark, N.J.
AAL: $2.06 billion, 5% increase from 2005

Swiss Re estimates that in 2012, Hurricane Sandy, which caused massive destruction in the U.S. Northeast, caused $35 billion in insurance losses.

"As illustrated by the recent landfall of Sandy on the East Coast of the United States, there is a need to prepare at the local, national and international level for larger floods and the disasters that ensue," says Nature Climate Change. 7. Tianjin, China
AAL: $2.27 billion, 26% increase from 2005

Tianjin's manufacturing industry, including an airline assembly factory, makes up the majority of the city's economic output. Any deluge that hits this city nestled between the Hai, Yellow and Yangtze rivers would have drastic effects; thus, in May 2012 the city began a project that would increase Tianjin's drainage capacity. 

6. Miami, Fla.
AAL: $2.55 billion, 21% increase from 2005

"The U.S. appears particularly vulnerable, with three in ranking [in the top 10 at-risk cities] by relative AAL," states the Nature Climate Change report. "On average, however, rich cities are better protected than poorer ones, and the ranking in terms of absolute flood losses contains more cities from developing countries."

5. Shenzen, China
AAL: $3.14 billion, 7% increase from 2005

Shenzhen is a major city in South China's Guangdong Province, one of the nation's most flood-prone regions. Marsh & McLennan says a lack of penetration is a major issue in China, although the national government has increased funding for flood prevention projects and flood storage basins.

4. Guayaquil, Ecuador
AAL: $3.19 billion, 13% increase from 2005

The largest, most populated city in Ecuador sits on the banks of the Guayas River, which is fed by the Pacific Ocean. It is poised to become one of the nation's poshest areas, but is highly prone to flooding due to its closeness to sea level and taxed sewage system. The city experienced destructive flooding and mudslides due to heavy rain in March 2013. However, Guayaquil has undergone electric and road infrastructure projects in recent years.

3. Kolkata, India
AAL: $3.35 billion, 24% increase from 2005

Kolkata, or Calcutta, is a commercial and cultural center with upwards of 4 million residents, which houses India's oldest operating port.  Kolkata is one of two Indian locations on the list of top 10 cities at risk of coastal flood damage. According to Towers Watson, the Indian non-life industry is growing fast, registering $176.4 billion of total gross written premium income in spring 2012, a nearly 20 percent increase from the previous year.

2. Mumbai, India
AAL: $6.41 billion, 5% increase from 2005

Formerly known as Bombay, Mumbai is the world's fourth most-populous city, and home to 26 billionaires (more than live in Shanghai, Paris or Los Angeles). Located on India's west coast, it has a deep harbor and rich economy: it is the center of the Bollywood movie industry as well as the Reserve Bank of India, the Insurance Institute of India, and the country's major stock exchanges.

1. Guangzhou, China
AAL: $13.2 billion, 11% increase from 2005

Guangzhou, China's third largest city, is the capital of China's Guangdong province. Home to nearly 13 million people, it is a transportation and trading hub situated on the Pearl River, just 75 miles northwest of Hong Kong. It is a "Beta World City", or global economic node, as categorized the Globalization and World Research Network.