How climate change is affecting the Thanksgiving table

Turkey with mashed potatoes and chunky cranberry sauce.

Climate change is already reshaping many facets of human life, like where we live and how we move around. It’s also, increasingly, changing how we eat, by disrupting crop growth and other aspects of food supply chains.

Last year, the Globe took a look at how the climate crisis is threatening our ability to enjoy classic Thanksgiving dishes. With the holiday upon us once again, we’re revisiting the story.

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I’ve got a lot to be thankful for this Thanksgiving: my health, the ability to finally gather with family, the time I have off from work to relax. I’ll also be expressing my gratitude for the food on the table, especially because many of the season’s classic dishes aren’t promised in the future. Here’s how three of my favorite Thanksgiving staples are threatened by the climate crisis.

Cranberry sauce

Cranberries are a Thanksgiving staple, especially in Massachusetts where they’re the most-grown crop. But shifts in the climate are making them harder to grow.

The berries are native to the region, and they’ve evolved to withstand extreme temperatures and rainfall patterns. But despite their toughness, Brian Wick, executive director of the Cape Cod Cranberry Growers’ Association, says erratic weather fueled by climate change has put them at risk.

“Last year, there was a record drought in southeastern Massachusetts that impacted the harvest with small berries,” he said. “They didn’t all make it to the harvest due to the extreme, dry conditions.”

This year, we had no shortage of rain as Massachusetts saw one of its wettest summers on record. Yet too much water can also pose issues because moist conditions can allow fungus to grow and spoilage to occur.

“A lot of fruit rotted before harvest last year,” Wick said.

In addition, every few years, growers have traditionally driven across the ice to put a fresh layer of sand onto cranberry bogs, which acts as a natural fertilizer. These days, however, winters are rarely cold enough to form ice layers thick enough to traverse.

Like the crops themselves, cranberry farmers are resilient and have already started to adapt to these changes. Many are using new equipment, changing their fertilizing schedules, and switching to hardier varietals.

“Our growers need to be able to persevere, and they will,” Wick said. “But it’s, it’s going to take some investment in the industry over the next period of years to stay sustainable and economically viable.”

Mashed potatoes

I can imagine Thanksgiving without cranberry sauce, but I can’t bear the thought of it without mashed potatoes, which climate change is unfortunately also putting at risk.

In the United States, the most common kind of potato is the Russet Burbank, which is conveniently also the variety often used to achieve a fluffy, lump-free mash. But the area where Russet Burbanks are most often grown, the northwest, is changing.

Potato farmers in the region rely on the slow melt of snow from the mountains to irrigate their crops. Yet as the northwest gets warmer, less snow is accumulating — a 2018 analysis found that mountains of the western United States now see between 15 to 30 percent less snow than they did in the middle of the 20th century, and a 2021 analysis found that by the 2070s, the region could have no snowpack at all. That can leave soil parched, and hot weather can dry it out even further, making it very difficult to successfully grow potatoes.

If climate change continues to get more severe, potatoes will be even more endangered. One 2017 paper found that by 2055, global potato yields could fall by up to 6 percent from current levels due to climate change. By 2085, if world leaders don’t take urgent action to curb greenhouse gas emissions, they could drop by up to 26 percent. As though we needed another reason to implement climate policy.

Pumpkin pie

Climate change is also impacting the arguably best part of the Thanksgiving lineup: pumpkin pie.

Illinois, the United States’ top pumpkin producer, is getting much hotter and wetter due to the climate crisis. The heat can cause pumpkins to ripen too quickly and rot, and the excessive rain can threaten pumpkin crops, too.

“Persistent heavy rainfall in the spring can delay pumpkin planting, which in turn often results in harvest delays and an increased risk of crop loss,” Trent Ford, Illinois’ state climatologist, said. “Additionally, planting pumpkins in excessively wet soils increases the risk of disease.”

These changes are already visible. In 2015, the town of Morton, Ill. — which produces a stunning 85 percent of the world’s canned pumpkin — saw an abundance of rain that cut the country’s canned pumpkin supply in half.

National data show that Illinois could get even wetter in the future, and according to a 2015 paper, due in large part to all that additional rain, average statewide crop yields — including pumpkin yields — could drop by 73 percent by 2100 from 2015 levels. That means the canned pumpkin situation could get even worse.

Ford called on scientists to more closely examine how climatic shifts will impact pumpkin growers. “There has been little research done on the impacts of climate change on pumpkins, relative to commodity crops like corn and soybeans,” he said.

Thankfully, this year, pumpkin yields seem to be doing just fine despite heavy precipitation. But I know I’ll never take pumpkin pie for granted again.