A year ago, we were tallying the damages from 2017, a record year of weather and climate-related disasters: a triple whammy of major hurricanes, including Hurricane Maria, and several huge wildfires and floods. All told, it came out to about $306 billion, making it the most expensive year for disasters in US history.

The National Oceanic and Atmospheric Administration on Wednesday released their damage estimates for 2018. The total? At least $91 billion. While that may look small compared to 2017, make no mistake: Extreme weather hit us hard in 2018, taking hundreds of lives and tens of thousands of homes and livelihoods.

2018 brought Hurricane Michael, which struck the Florida coast in October, and the Camp Fire, California’s deadliest and most destructive fire on record. The Camp Fire alone racked upward of $13 billion in losses, according to CoreLogic, a property analytics firm. Hurricane Michael is estimated to have cost the US economy at least $25 billion.

The causes of these and the other major disasters of 2018 were complex, with many contributing factors. But climate change played a supporting role in many of them, creating riskier conditions for storms and fires to arise in.

And while President Donald Trump and Republicans in Congress continue to recklessly deny the short- and long-term risks of climate change, more and more Americans are waking up to the fact that the damages from weather and climate disasters will only grow only more severe as the climate crisis accelerates. Here’s what we learned from the heat waves, hurricanes, wildfires, and droughts that befell America last year, and the lessons they offer for how to prepare for the future.

1) Climate change was an indisputable force in this year’s disasters

From rising sea levels to more extreme heat, the raw ingredients for many natural disasters are getting stronger, the reports from the United Nations’ Intergovernmental Panel on Climate Change and the US government’s National Climate Assessment confirmed.

And while we still have plenty to learn about how global warming is affecting extreme weather, several events in 2018 were instructive, showing us how much work we have to do to prepare for a warmer, less stable climate.

Heat waves can be deadly, and climate change is making them more frequent

Scientists say that the increasing frequency, intensity, and duration of heat waves are some of the strongest signals of climate change. More Americans die from heat-related illnesses than from any other weather event, and the number will likely grow as humans continue to spray heat-trapping gases into the atmosphere.

2018 is on track to be the fourth-hottest on record. Over the summer, deadly heat baked many parts of the world, including the United States. Chino, California saw a record 120 degrees Fahrenheit in July. This proved especially dangerous for people who had to work outside: Several US workers died on the job from the heat this summer.

But we saw again this year that temperatures don’t have to rise to triple digits before they become dangerous. In fact, it turns out heat waves tend to be more dangerous in cooler climates, where high temperatures are a larger deviation from the norm. This heat is especially dangerous for the elderly, many of whom already face heart and lung problems.

It’s been another devastating year for wildfires, and the risks are growing

The massive, almost year-round wildfires we’ve been seeing in the western US can scarcely be described as “natural.” While wildfires are an important part of many ecosystems, the destruction wrought by the towering infernos we saw this year like the Carr Fire in July were worsened by human activity.

First, people ignite the vast majority of fires. The Carr Fire, for example, was started by sparks from a broken-down vehicle. The likelihood of igniting wildfires continues to rise as populations grow and people build their homes closer to fire-prone areas. This also increases the damage from the fires that do occur, since property ends up so close to flammable vegetation.

Policies like active fire suppression have also paradoxically increased the risks from wildfires. By extinguishing smaller blazes, leaf litter, shrubs, and small plants build up in forests, increasing the fuel load.

The role of climate change in wildfires also got a lot more attention this year. Scientists reported that climate change accounts for 55 percent of the increase in dryness in Western forests. This has doubled the area burned by forest fires. Persistent drought, heat, and bark beetle infestations have combined to kill off 129 million trees across California.

We saw these signals converge ahead of the Camp Fire, California’s single-most deadly and destructive fire. The blaze was likely ignited by power lines in an area of dry forest. It then rapidly engulfed entire towns nestled into the forest and torched 150,000 acres.

However, the climate signal is weaker in chaparral landscapes, like those around Los Angeles. The vegetation in dry, grassy regions tends to grow quickly, so years of drought don’t have as strong an effect as they do on forests, where the trees take decades to grow.

That may change in the future. In a study published in Environmental Research Letters in 2015, researchers reported that the area burned by wildfires will increase by as much as 77 percent by 2050 due to climate change.

The consequences of fires don’t end with the flames. The smoke from this year’s fires shrouded cities like Seattle and Sacramento in some of the worst breathing conditions in the world. For residents, it was like smoking more than a dozen cigarettes. So as fires grow larger, so too will the risks from poor air quality.

Massive rainfall events are on the rise

In a devastating turn of fate, some of the areas scorched by fires last year were hit by massive flooding early this year. Huge amounts of rain forced evacuations in California as the freshly denuded landscape threatened mudslides.

Flash floods following huge rain storms also struck other parts of the country. In May, Maryland was drenched in more than 8 inches of rain in just two hours, turning streets into rivers. It was the second time in two years such a flood occurred.

Both the amount and the rate of rainfall are some of the strongest signals of climate change. As air heats up, water evaporates faster. And for every degree Celsius increase in temperature, air can hold 7 percent more water.

According to the National Climate Assessment, average annual rainfall across the US has gone up by 5 percent since 1990. Extreme rainfall events are also increasing in part due to climate change, and nine of the top 10 years for extreme one-day precipitation events have happened since 1990.

2) Hurricanes rapidly intensified into dangerous storms. There may be more rapidly intensifying tropical cyclones to come.

Early in October, the National Hurricane Center issued a five-day forecast showing Hurricane Michael making landfall near Mexico Beach, Florida. It predicted that the storm would arrive with 80 mph winds.

Yet the storm that arrived October 10 was not like the one expected. It was an extremely intense Category 4 storm with 155 mph winds. Measured by barometric pressure, Michael was one of the top four most powerful storms to ever make landfall in the US. When it came ashore, meteorologists say, it was like a 20-mile-wide tornado. The gulf-side town of Mexico Beach, Florida, was all but flattened from the onslaught.

This year’s hurricane season was not particularly unusual compared to the long-term average. There were eight hurricanes (there’s usually 6.3 on average).

Today is November 30 - the official end of the Atlantic #hurricane season. The season overall was slightly above normal, with 15 named storms, 8 hurricanes and 2 major hurricanes. Average is ~12 named storms, ~6 hurricanes and ~3 major hurricanes. pic.twitter.com/NAKDFvsJVQ — Philip Klotzbach (@philklotzbach) November 30, 2018

But the hurricanes that did hit the United States landed a powerful punch. In September, Hurricane Florence hit the Carolinas, and dumped upward of 35 inches of rain in places and more than 10 trillion gallons across North Carolina, South Carolina, and Virginia.

Florence made landfall in North Carolina near Wilmington as a hurricane, then slowed down to a sluggish 2 miles per hour. It stalled over the Carolinas, bringing incredible amounts of rain to the region. These numbers make Florence comparable to last year’s Hurricane Harvey, which stalled over the Houston area and broke the national rainfall record for a single tropical storm. It dumped around 27 trillion gallons of water in total and destroyed around 30,000 homes.

Florence, like Michael, also rapidly intensified, growing from a tropical storm to a category 4 hurricane in just two days.

Atmospheric scientists suspect that in a warming world, rapid intensification of storms will become more common, fueled by increased sea temperatures.

Hurricane Willa, which impacted Mexico, also rapidly intensified from 40 mph winds to 160 mph winds in just two days in October. Another tropical cyclone, Typhoon Yutu also very quickly intensified, transforming from a tropical storm to a massive dangerous typhoon— with 180 mph winds — in just two days. It was the strongest on Earth this year, tearing through the Northern Mariana Islands, a US territory in the Pacific, located near Guam. The eye of Super Typhoon Yutu passed directly over the islands Saipan and Tinian, flattening homes in its wake.

Overall, forecasting hurricane intensity is hard. Atmospheric scientists are much, much better at hurricane track forecasts (which are getting more and more accurate every year. ) Scientists don’t perfectly understand the mechanisms that lead to rapid intensification. But these rapidly intensifying tropical cyclones may be a sign of what’s to come.

3) We’re still not planning adequately for these disasters

Since 1980, the United States has suffered 238 disasters with billion-dollar-plus price tags. The total bill tops $1.5 trillion, according to NOAA.

The alarming regularity of extreme weather and climate events means that public officials need to stop thinking of them as one-off emergencies and start planning for them as regular events. That means carving out large provisions in budgets to pay for disasters. It also requires difficult decisions about where to rebuild, what to protect, and who gets left behind.

We’re getting much better at anticipating and tracking calamities. We can now forecast hurricanes 72 hours in advance more accurately than we could predict their paths 24 hours in advance in 1990.

But even when we see the risks and vulnerabilities, we have a hard time getting out of the way. Residents in Paradise, California, which burned down in the Camp Fire, were wary of the dry trees around their properties for years, but many could not afford to go anywhere else. At Tyndall Air Force Base on the Florida coast, more than a dozen F-22 fighter jets were left in the path of Hurricane Michael in part due to the immense logistics that surround the Air Force’s most high-tech aircraft.

We were also reminded this year that after storms pass and flames burn out, people can continue suffering from a disaster. Puerto Rico’s blackout from Hurricane Maria spanned nearly a year, causing havoc for the island’s health, economy, and safety, which in turn contributed to an estimated 2,975 deaths.

This year’s disasters are going to haunt us for months, if not years, as well. The Camp Fire destroyed nearly 10,000 homes in California. Residents are now jumping into one of the tightest and most expensive real estate markets in the country. Disaster managers are moving many of the people who lost their homes into longer-term shelters.

But that still leaves a major question: Should people rebuild their lives where they once were, or move on to safer ground? People around the country will increasingly be asking themselves this question, as the changing climate renders the future more uncertain.