The survey of 150 UK and European companies revealed that 87% of businesses surveyed see climate change as the single biggest threat in terms of risk and growth, ahead of terrorism, pandemic flu, flooding, and the credit crunch.
Following the floods of 2007 and the recent storms, 74% of businesses see adverse weather as a real threat.
Although 70% said they were prepared, 40% of small manufacturing firms and 50% of large retail firms admit to not having a plan in place.
The survey also found 83% of businesses were concerned that traditional sources of energy would become scarce and the cost of oil and gas would rise to adversely high levels in the next five years, with 60% saying they were not prepared.
Martin Caddick , leader of the business continuity management team at insurance and risk advisory firm Marsh, said while most firms had accurately identified climate change and energy risk among the biggest challenges, fewer had been successful in tackling them head on.
"A lack of preparedness continues to be a major issue for European firms in today's turbulent times," he said.
The survey also showed shortcomings and risks of outsourcing and offshoring practices as another top concern.
More than half (65%) those surveyed said they were worried that they had underestimated and poorly understood the associated risks, 61% were concerned about the failure of suppliers, and 46% said they were not prepared for interruptions to services.
On financial concerns, the survey found that 33% of businesses believe they will be affected by subprime lending and the credit crunch, with 40% of those saying they were not prepared for the effect that would have on them.
More than half (60%) of businesses said they were concerned about a terrorist attack on UK soil within the next 18 months.
Although 73% said they were prepared, 75% of large manufacturing companies admitted they had not planned for such an event.