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The High Battery was battered by waves as Tropical Storm Irma hit Charleston's peninsula in 2017. Brad Nettles/Staff

If carbon emissions are not radically cut by 2030, Charlestonians could see far stronger storms and the disappearance of shellfish habitat, according to a new broad-based review of climate change science. 

The report, published this month by the United Nations' Intergovernmental Panel on Climate Change, compared greenhouse gas-caused atmospheric warming of 1.5 degrees Celsius (2.7 degrees Fahrenheit) with 2 degrees Celsius (3.6 degrees Fahrenheit) — the benchmark that has outlined large-scale agreements like the Paris Climate Accord. 

Failing to limit warming at 1.5 degrees could trigger some of the most dire changes to the climate. The IPCC report has reverberated throughout the world since its publication, but its warnings weren't necessarily shocking, said Kirsten Dow, who studies climate at the University of South Carolina. 

"It's not surprising to hear at all that there are going to be serious impacts at 1.5 degrees," Dow said. "The climate is dangerous now."

Here are some of the biggest effects that climate change could bring:

1. Harsher hurricanes

Warmer air and oceans are already challenging the world's best hurricane forecast models, as storms become more intense. In some cases, they are becoming bigger, wetter and slower, challenging emergency officials who have tended to focus on high winds and the threat of storm surge more than flooding from heavy rains. 

In short, extreme weather is expected to become the norm, but storms aren't the only events that will become more intense.

Droughts are expected to worsen as well, when they hit. The IPCC report specifically mentions sub-tropical climates, like Charleston's, as those that could become drier overall. 

2. Dwindling oysters 

Warming above 1.5 degrees poses serious threats to ocean food webs around the world. It could prove particularly harmful for the shellfish along South Carolina's coast, which are ecologically important because they clean the water as they filter-feed. 

Shellfish are also an important local product for Charleston's food scene and a livelihood for the region's local growers and harvesters.

But sea level rise could make their habitat disappear, and researchers have already found that the state's salt marshes are losing ground. Ocean acidification, another byproduct of climate change, also poses a high risk to the life cycle of bivalves like oysters, according to the IPCC report.

3. Worse flooding 

Flooding has long been a persistent issue in low-lying Charleston, with threats coming during tropical storms, but also during pop-up events like the downpour this July that closed roads around the region and snarled traffic downtown just in time for the morning commute. 

Compounding the issue is sea level rise, which would make flooding more likely during king tides and hard rains. 

In addition to flooding, a rising sea level means brackish water moving farther inland, which can lead to salt intrusion into groundwater. Most water utilities in the Charleston area draw from local rivers, reservoirs and aquifers, but individual private wells could be affected as saltwater creeps farther inshore.

4. Higher electric bills

According to a forthcoming report on climate risks from the Environmental Protection Agency, parts of South Carolina could see more than 100 90-degree days a year by 2030. Typically, Charleston has seen about 53 annually, according to the Southeast Regional Climate Center. 

As temperatures rise, that means more days when it's too hot to be inside without an air conditioner running. That means increased energy costs for residents of the Palmetto State, who already paid the most in the nation for electricity in 2016. 

A hotter environment isn't just expensive day to day: It's also a threat to human health.

In addition to illnesses like heat exhaustion and heat stroke, a hotter atmosphere can exacerbate smog, and there's evidence that it may also increase the incidence of asthma.

5. Wealth transfer 

As the climate warms, residents of South Carolina who depend on farm work or other jobs that require them to be outside simply may not be able to work. 

The EPA report points out the Southeast as particularly vulnerable to the potential of higher temperatures hitting the brakes on many kinds of labor.

The region could lose $47 billion annually in wages by 2090 if nothing is done to mitigate carbon emissions. 

And Dow points out that infrastructure vulnerability from flooding and other impacts also could create wide-reaching economic effects, particularly for the Charleston area. 

"The Port of Charleston and all the economic development that depends on the well-being of our transportation infrastructure up and down Interstate 95, we should be looking at that," Dow said. 

Reach Chloe Johnson at 843-735-9985. Follow her on Twitter @_ChloeAJ.