Last year’s one-two storm punch already had officials wondering if climate change was to blame for what has been described as a 100-year event. Now, as pictures of damage from Hurricane Sandy begin to pour in, the question of climate change is being raised again.

It’s something to which the Department of Energy and Environmental Protection has been paying attention. The DEEP issued a draft report on the topic in 2011.

“This raises real questions about historic assumptions and 100 year storms and whether or not we’re going to see them at a frequency that is more often than 100 years,” DEEP Commissioner Daniel C. Esty said Monday after a briefing in the Emergency Operations Center.

It has been 25 years since the last hurricane and now that the state has seen two in a row, it “gives rise to concern both about the frequency and the storms we need to prepare for going forward,” Esty said.

The storms have consequences with respect to the types of infrastructure investments the state plans to make going forward, he added.

Esty said he gives credit to Gov. Dannel P. Malloy and the Two Storm Panel, which already has flagged this as an issue for the future both in the draft report issued by an advisory panel and in the energy strategy document released by Malloy a few weeks ago.

He said the siting of sewage treatment plants and other public infrastructure, which have existed in the state since the 1950s, may no longer be seen as good locations based on the history of the storms. He said the electrical equipment at new sewage treatment plants is being stationed up a flight of stairs now so there’s less of a risk it will be compromised by flooding.

Esty was careful to say the storms, including Sandy, are not necessarily “evidence of climate change.” However, “what prudence argues is what the climate scientists believe is potentially happening is the increased intensity and frequency of wind storms, including hurricanes in Connecticut, and that a thoughtful state government would take that into account and plan for it.”

Sandy came ashore in New Jersey as a Category I hurricane, but Esty said the state is going to need to plan for bigger, more frequent storms in the future.

A draft 2011 report from the Department of Emergency Services and Public Protection found the maximum wind gust from Tropical Storm Irene was 66 mph. An estimated 2 to 3 percent of trees within 50 feet of the center line of state roads were felled by the storm.

Things could have been much worse.

The draft report found that if it was a Category I hurricane, an estimated 180,000 trees would fall resulting in about 150,000 trouble spots and nearly a complete outage of the state requiring 67 days for full restoration. If it were a Category III hurricane, 420,000 trees would fall resulting in about 350,000 trouble spots and a 100-percent outage of the state requiring 157 days for full restoration.

Tropical Storm Irene and the October snow storm each knocked out power to more than 800,000 customers, far exceeding any storm in recent history.

“However, they pale in comparison to the damage that will be inflicted on Connecticut by a Category 3 hurricane with sustained winds between 100 to 120 mph,” the recommendation from the Two Storm Panel states.

Testimony provided to the Two Storm Panel by meteorologists from the National Weather Service stated that Connecticut is overdue for a major hurricane and data from the Northeast Regional Climate Center indicates a major increase in precipitation over the last 40 years.

According to a report entitled “Severe Weather In North America” and published by Munich Re, a reinsurance company, “Nowhere in the world is the rising number of natural catastrophes more evident than in North America.”

“The study shows a nearly quintupled number of weather-related loss events in North America for the past three decades, compared with an increase factor of 4 in Asia, 2.5 in Africa, 2 in Europe, and 1.5 in South America,” according to a press release about the report.

Climate change affects the formation and intensity of heat-waves, droughts, hurricanes, cyclones, and other extreme weather events.

But whether it’s real or not is still being debated.

In 2009, Rep. John Piscopo, R-Thomaston, introduced a bill to repeal Global Warming legislation. It would have forced the state to leave a Regional Greenhouse Gas Initiative compact, which “creates a regulatory structure for incentives and penalties designed to reduce carbon emissions.” It died in committee on a voice vote.