3 takeaways from a landmark Surgeon General’s report on the US loneliness crisis.
The US Surgeon General is sounding an alarm: Americans are more lonely and socially disconnected than ever, and it’s a serious threat to their physical and mental health that demands urgent policy action.
A new report from the Surgeon General says that social isolation’s effects on mortality are equivalent to smoking 15 cigarettes every day. Social isolation (an objective measure of lacking connection to families, friends, and community) and loneliness (a subjective measure of feeling disconnected) contribute to a person having a higher risk of heart disease, stroke, anxiety, depression, and dementia, and make people more susceptible to infectious diseases.
Those individual health effects ripple out into the broader community. Communities with more social cohesion have less disease and lower all-cause mortality than those with less so-called social capital. They are better prepared for natural disasters and experience less violence.
Reports from the surgeon general are reserved for urgent public health issues that require immediate action — and the nation’s top public health official argues that loneliness and isolation qualify.
“Given the profound consequences of loneliness and isolation, we have an opportunity, and an obligation, to make the same investments in addressing social connection that we have made in addressing tobacco use, obesity, and the addiction crisis,” Surgeon General Vivek Murthy wrote in the opening of the report.
The advisory breaks down the measures of social isolation and loneliness in the US, how they can affect people’s health, and introduces recommendations about how to being to alleviate this epidemic of loneliness. Here are the report’s main takeaways.
- Americans are lonelier and more isolated than ever
Americans are experiencing more loneliness and isolation than at any time in recent memory. Those trends were already underway well before the Covid-19 pandemic, though living through three years of a public health crisis has likely accelerated them, at least for some people.
Half of Americans say they experience loneliness, according to several recent surveys: Less than 40 percent said in a 2022 study that they felt very connected to others.
Loneliness is subjective, and the report notes that a certain amount of solitude, even undesired solitude, can help people become more resilient. But more objective measures also reveal a country in which people are increasingly isolated from one another.
In the 1970s, almost half of Americans (45 percent) said they could generally trust other people, according to the surgeon general’s report. Today, less than a third say the same. The amount of time that Americans say they spend alone every day had risen by nearly 30 minutes from 2003 to 2019 and increased another 20-plus minutes in 2020, the first year of the pandemic, which amounted to almost an additional full day of solitude over the course of a month. The amount of time that young people (ages 15-24) spend with their friends in person dropped by nearly 70 percent from 2003 to 2020, as long-running trends got worse when the pandemic set in. Half of the country says they have three or fewer close friends, double the number from 1990. Just 16 percent of Americans say they feel very attached to their local community.
The causes for this increasing isolation are complex. People are less likely to get married and are having fewer children. Americans are much less likely to belong to religious organizations, a historical source of community connection. These are legitimate lifestyle choices. But, as the report notes, people need to be aware of the risks that loneliness brings to their health in order to better appreciate the need to seek out social connection.
Other risk factors for loneliness include being a racial or ethnic minority or identifying as LGBTQ, experiencing discrimination, having a lower income, and living alone. Being in poor physical or mental health is also associated with more isolation, suggesting a feedback loop in which loneliness not only contributes to poor health but perpetuates it. The percentage of households that comprise a single person living by themselves has doubled from 1960 to 2022, to the point that now nearly one in three Americans lives alone.
The role of technology in fostering loneliness has been scrutinized lately, but the report notes that the relationship is complex. Social media can create opportunities for people to connect with others, but it can also exacerbate loneliness. People who spend more than two hours a day on social media or who are the targets of online harassment report feeling more isolated from other people.
The pandemic likewise had a mixed effect on people’s connection to other people. About one in four Americans said they felt less close to their family at the beginning of Covid-19, but one in five said they felt more connected, an indication that perhaps “the pandemic exacerbated existing family dynamics of connection or disconnection,” according to the report.
What’s clear from the surgeon general’s report is that neither the pandemic nor technology should be seen as unique causes of this loneliness epidemic, but instead as accelerants. The broader social infrastructure — both cultural and physical — must be addressed in order to alleviate people’s isolation. Because it is quite literally killing them.
- Loneliness and social isolation negatively affect a person’s and a community’s health
How does isolation affect a person’s physical and mental health? The relationship is once again multifold: physical, psychological, and behavioral.
Isolation can lead to a person experiencing a higher amount of stress, which affects mental well-being as well as causing the body to release stress hormones. Those hormones can contribute to higher levels of inflammation, which is associated with a wide spectrum of health problems. People with stronger social connections are also more likely to behave in ways that lead to better health: more physical activity, better nutrition, and even better management of chronic diseases.
The empirical evidence is consistent: More social connection is linked with better health outcomes and vice versa. The surgeon general’s report notes that one of the first large-scale epidemiological studies, conducted in the late 1970s, found that people with a low amount of social connection were more than twice as likely to die during the study period as people with high social connection, even after adjusting for age, health, and economic status. A more recent systemic review of the available research also found that a high level of social connection led people to be 50 percent more likely to survive over a long follow-up period, which averaged 7.5 years across the nearly 150 studies included in the review.
As the report concluded in one of its most striking passages:
Indeed, the effects of social connection, isolation, and loneliness on mortality are comparable, and in some cases greater, than those of many other risk factors including lifestyle factors (e.g., smoking, alcohol consumption, physical inactivity), traditional clinical risks factors (e.g., high blood pressure, body mass index, cholesterol levels), environmental factors (e.g., air pollution), and clinical interventions (e.g., flu vaccine, high blood pressure medication, rehabilitation).
Social isolation is associated with higher rates of heart disease, stroke, hypertension, and diabetes. People with stronger social connections are correspondingly less likely to be readmitted to a hospital after being treated for heart failure and they are generally better at managing chronic conditions like diabetes than people who are more isolated.
Loneliness also comes with the expected effects on a person’s mental well-being. More isolation is linked to higher rates of anxiety, depression, and self-harm, even if once again the report cautions that these outcomes have complicated origins. But the connection is unavoidable: One study found that men who live alone are twice as likely to die by suicide.
These trends apply not only at the individual level, but also to entire communities. Communities with higher social capital — which can be linked to family structure and involvement, trust in community institutions, popularity of volunteerism, levels of participation in political discussions and voting efforts, and cohesion among community members — experience better health.
One study found that a 10 percent increase in the number of people in an area who say they feel connected to others was associated with an 8 percent drop in all-cause mortality. A county-level analysis of deaths during the Covid-19 pandemic found that “lower levels of social capital were associated with a higher number of cases and deaths from COVID-19 infection,” the report noted.
Those population-level effects trickle down to communities with more social cohesion having better experiences during natural disasters (in part because of better preparation) and seeing less violence.
- How the US can begin to address its loneliness epidemic
So the problem is clear. Objectively and subjectively, Americans are more isolated and lonely than ever. That isolation leads to worse health outcomes at both the individual and community level.
So what do we do about it? The Surgeon General’s office sketches out the principles upon which a successful strategy to alleviate the US loneliness epidemic could be built.
The underlying causes here span from the individual (chronic diseases, personality, socioeconomic status) to the relational (household, quality of interpersonal relationships) to the community (outdoor spaces, community organizations, health systems) to the societal (norms and values, civic engagement, historical inequities).
The report includes a long appendix with recommendations targeted to specific organizations at different levels of society, from the government (federal, state, and local) to individual physicians, academics, schools, employers, and even the media.
But in broad strokes, the report recommends six pillars for making Americans feel more connected and less isolated from one another:
- Strengthen the social infrastructure: more communal spaces, more social activities, and better infrastructure to help people access them
- Develop “pro-connection” public policies that account for the need to foster connection when passing laws or formulating regulations, from transportation to education to housing
- Mobilize the health sector: train health care providers to identify people at risk of isolation and better equip providers to connect patients with the other forms of social support they may need
- Reform digital environments: require more transparency from large tech companies and establish safeguards (such as restrictions for young people) that could ameliorate the worst effects of social media on vulnerable populations
- Deepen our knowledge: support academic research and public information campaigns to improve our understanding of the connections between isolation and health and make people more aware of the problem in the first place
- Cultivate a culture of connection: use all of the vectors available, from politics to entertainment, to reinforce the values of connection and reduce the polarization that can lead to people feeling more isolated in our modern age
These are enormous and daunting undertakings. But they are necessary, given the scale of the challenge before the country.
“We are called to build a movement to mend the social fabric of our nation,” Murthy wrote. “It will take all of us … working together to destigmatize loneliness and change our cultural and policy response to it.”
The philosopher Agnes Callard on pushing the boundaries of modern relationships.
If I asked you to imagine the stereotypical philosopher, who’s the first person that springs to mind? If it’s a historical figure, there’s a decent chance it’s Socrates. Which makes sense, since he’s arguably the founder of the entire tradition of western philosophy.
And even if you don’t know much about Socrates, you probably know at least one thing he said: “An unexamined life is not worth living.” That was the guiding principle of his life and it got him into all kinds of trouble in ancient Athens — most famously, leading to his public execution.
It would be way too much to call any current figure a modern-day Socrates, but when I think of public philosophers carrying out his legacy in their own way, I think of Agnes Callard. She teaches at the University of Chicago and is constantly writing for mainstream publications like the Atlantic and the New York Times.
Most recently, Callard was — how shall we put it? — “in the news” after the New Yorker’s Rachel Aviv published a profile of her and her highly unconventional marriage. If you’re interested in the details of that — including the fact that Callard lives with both her husband and ex-husband, all three of whom are philosophers — the piece is worth a read. But I saw it as a fascinating example of Callard’s willingness to think publicly and put herself out there.
She’s currently working on a book about Socrates (her philosophical role model), so I invited her onto The Gray Area to talk about her approach to public philosophy in general and her thoughts on love and marriage in particular. Below is an excerpt of our conversation, edited for length and clarity.
As always, there’s much more in the full podcast, so listen and follow The Gray Area on Apple Podcasts, Google Podcasts, Spotify, Stitcher, or wherever you find podcasts. New episodes drop every Monday and Thursday.
Sean Illing
Do you think that we expect too much from our relationships? Is it unfair or unreasonable to expect one person to be enough for anyone?
Agnes Callard
I think the question, do we expect too much, and the question of expecting one person to be enough, seems separate to me.
I think we don’t expect enough. I’m a Socratic about romance and romantic relationships, and Socrates’ theory of romance is that the way that we behave in connection with romance, is, he uses the Greek word maniae, Mania. It’s like we’re crazy. We become crazy. This kind of craziness, nobody actually thinks, “Oh, the person should be institutionalized or they need to get help.” We think, “Oh yeah, of course, they’re in love, so that’s normal.” We’ve decided that crazy is normal in a certain kind of context. And to show you how twisted that is, we could substitute another kind of motivation for romance. Like, say the thing that people do where, they keep calling their ex and they keep texting them and they hate this person now. And they don’t wanna get back together with them, but they can’t stop themselves texting them. Totally familiar phenomenon, right?
Imagine somebody did that with a restaurant. They wanted to go to a certain restaurant and the restaurant’s closed. So they stand outside the door of the restaurant and they’re banging on the door and you walk up to them and you’re like, “You know, this one’s closed. There’s all these other open ones. Do you want to go to one?” “No, I can only go to this one.” “Is it because the food is so good?” “No, I hate the food.”
If somebody did that with respect to food, we’d be like, there’s something wrong with you. You need help. But when we do it about romance, we’re like, yeah, that’s how it goes. So Socrates thinks this needs interpretation. We need a theory of why it is that this certain kind of craziness starts to take over us.
And his theory is that it’s a sign that we didn’t come from this place that we’re in now. We’re here, but our home is in another world. And in that other world, the rules are different and things are perfectly beautiful.
But of course the other person whom you’ve gotten this glimpse of perfection isn’t themselves perfect, and so what is it to hold onto that glimpse of perfection? I think Socrates thought that what it is to hold onto it is to try to reconcile yourself to the thought that it’s not actually in that person, but that that person could be a way of getting at it together with you.
Sean Illing
I had an excerpt from Plato’s Symposium read at my wedding — the famous speech from Aristophanes. Aristophanes is this comic figure, but in the Symposium, he’s being super serious about love. And he has this idea that at some point in our past, each pair of lovers were one whole and we were separated. And our great quest is to find that person again and reunite. That’s obviously not true, but it’s beautiful. And while I still think that speech is fantastic, I’m not sure it’s the right way to think about love anymore.
It sounds a lot like this notion that the person you love should complete you or help you complete yourself, which sounds a little bit like what you’re saying, unless I’m wrong about that?
Agnes Callard
So the way the Symposium was structured is it was a bunch of speeches and then there’s Socrates’s speech and then Alcibiades’s speech.
Socrates says, “I once heard a story about how lovers love their other half?”
He doesn’t name Aristophanes. It’s like a subtweet. “I once heard a story about how lovers love the other half. That story is wrong. That’s not what love is.”
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Courtesy of the University of Chicago
So Socrates explicitly comes out against Aristophanes and he says Aristophanes is wrong, don’t interpret my speech as saying the same thing as Aristophanes’s speech. Because Aristophanes’s speech suggests that all you gotta do is find your other half and then that’s it. You’re complete. And I think Socrates would say you’ve confused the beginning of the story for the end of the story.
Sean Illing
When talking about your divorce, you describe that feeling of losing the initial intoxication that comes with love. We all know what that’s like. I guess my question to you is, where does that leave you in the end? That feeling is never sustainable, right?
Agnes Callard
There’s certain feelings like when you first arrive at campus in your first day of classes or when your kid is born and you see them for the first time.
There are these kind of transformative moments that can’t last. And romance just gives us a big, strong version of that. That sudden experience of everything being possible, it doesn’t last. But I don’t think that’s the same thing as saying it’s not sustainable.
The feeling isn’t sustainable, that kind of excitement dissipates over time. But hopefully it doesn’t dissipate so quickly as for you to try to grab onto what is going to be this project that you’re going to engage in with this person.
I see falling in love as your chance to hook onto it, and in a way, that experience has to go away. Because that experience is the Aristophanic experience. It’s the experience of, “This person completes me, I’ve found my other half, I’m done.” It’s the experience of being done and in order to have the other experience of just getting started, that has to somewhat fade.
Sean Illing
If I understand correctly, the Socratic model of a good life is this attempt to get closer to our ideals. And when someone enters our life and helps us in that aspiration, that’s love and that’s great. And when someone doesn’t do that for us anymore or we don’t do that for them, maybe that’s the time to part ways. And that doesn’t necessarily make your marriage a failure or anyone’s marriage of failure. But let me push back a little bit on this.
You poke fun at your own selfishness in that New Yorker profile. And I wonder if you think it’s possible that this is too self-centered, a way of thinking about marriage and family and maybe even life itself? Maybe the point of these experiences is precisely to give ourselves over to other people to care less about ourselves.
Agnes Callard
There are bad kinds of selfishness. Let’s say, there’s a narrow kind of selfishness that is born from an impoverished sense of what yourself is, but there’s bad kinds of selflessness that are just born from conformity and a narrow set of expectations as to what other people want. I think what’s enticing about another person in the context of love and also in some other kinds of philosophical context is that they bring out possibilities for yourself that you didn’t know were there before. In that sense, it can also be selfless because it’s also directed toward their self, but there are many forms of selflessness that are very unromantic and that people don’t really want from us.
So I think it is a bit selfish, but as long as it’s a kind of enlightened selfishness, I’m okay with that. And at that point, I’m not sure that it is so different from at least one kind of selflessness.
Sean Illing
What role is there in this model of love and marriage for sacrifice?
Like what role is there for the other? And I don’t mean the other merely as a vehicle for our own philosophical growth, but the other, for the sake of the other? If we live entirely or too much for ourselves following our own passions, then I think we can end up bulldozing over the lives of the people we love. But there are higher and deeper forms of love, right?
Agnes Callard
I think that love involves something known as sacrifice. It involves unpleasantness. It’s a package deal and part of the package is suffering. It’s true of just about every attachment that you have to another human being — it comes with suffering. But, I guess the reason to stick with it and to continue is the good things that are to be gotten for you. I want to be with someone where they’re getting incredible value out of this relationship.
Sean Illing
What should we be expecting of our lovers that we don’t?
Agnes Callard
When you fall in love with someone, you see something divine in them, and the expectation would be that that gets realized. Because the thing you see is only a possibility, and that they have the same expectation of you.
Now, I want to acknowledge something, which is one reaction that this [New Yorker] piece got from a lot of people is like, wow, she seems really exhausting.
And I think that that’s sort of true about me, and maybe there’s just different modes of living. One thing I think philosophers are insufficiently sensitive to is the fact that people are different from other people. There’s just a huge amount of variance among human beings.
One way to think about it is, there are two kinds of people. Some people think the worst thing in life is stress and suffering and the world making too many demands of you, and then other people think the worst thing in life is boredom and nothingness and having an insufficient number of demands being made on you.
I am definitely in the second category. I just always want there to be more. I want everything to happen faster. So I guess the question is, which danger are you more worried about? The thought that failing at this really big task is going to be so dispiriting that you’ll just give up and won’t try at all? Or the thought that not putting a big enough task in front of you is just going to leave you demotivated and think, ah, is this even worth trying?
I’m just more in the second category. Just because something is an infinitely large task, I don’t think that means that it’s too big to ask of someone. But keep in mind, I don’t have to persuade everyone. I just have to persuade the person I’m with. So if most people are like, “Hey, that’s not for me,” that’s okay because I’m not romantically involved with them.
Sean Illing
When I think of Socrates, I think of someone who’s just poking holes in what we think we know. I wonder what you think we need most from philosophers today. What other sorts of questions do you think we should be asking right now of philosophers in particular?
Agnes Callard
I would agree with the description of Socrates as poking holes in things. But the way that I would put that is that he’s opening a bunch of inquiries. He’s saying, “Hey, here’s a bunch of stuff you’re just sort of doing. You’re just sort of going through your day with it, but you could ask about it.” I think the really interesting thing about marriage and romance is just that it’s a place where we will tolerate this, because we are all interested in having philosophical discussions about our romantic lives. And I never realized this so strongly until this piece came out.
I’ve had people report on me and describe me as someone, most of whose work is about romance or my own romances or whatever and none of my academic work is about this and very little of my public philosophy is about this, but people have this impression that’s who I am. Why? Because it’s really gripping to people. And I think this might be the thin edge of the philosophical wedge. If we philosophers want to get people to be interested in their own lives, the place we have to start is romance and marriage, because they will tolerate it there.
People will have long, involved conversations about ideas if those conversations are about romance.
To hear the rest of the conversation, click here, and be sure to follow The Gray Area on Apple Podcasts, Google Podcasts, Spotify, Stitcher, or wherever you listen to podcasts.
Kelp forests are majestic, life-sustaining ecosystems. Climate change imperils them.
A few miles west of San Diego is a stretch of ocean that’s rather unremarkable from the surface. The water is cold and blue. There’s some green seaweed peeking out.
Sink below the waves, however, and a whole other realm appears. Under the sea here, near Point Loma, is a forest as beautiful as any other. It’s made not of trees but of strands of giant kelp, a species of algae that can grow taller than a 10-story building.
Tethered to the seafloor and buoyed by air-filled chambers, the kelp strands undulate with the current, moving in slow motion. Schools of fish, seals, and other aquatic critters weave through the stalks like birds through a forest canopy.
“Diving into a forest is like descending into a cathedral,” Jarrett Byrnes, a marine ecologist at the University of Massachusetts Boston, said of kelp forests. Light from the surface filters through blades of kelp as if they’re stained glass, said Byrnes, who’s been diving kelp forests for more than 20 years. “It’s just amazing.”
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Our planet has a number of great forests — the Amazon, for example, or the boreal forest of Canada and Russia. These iconic ecosystems not only support an incredible diversity of wildlife but store vast amounts of carbon that might otherwise heat up the planet. It’s not hyperbole to say that our existence depends on them.
But equally important are the forests of the sea. Found in cold waters across roughly a quarter of the world’s coasts, kelp forests are the foundation of many marine ecosystems. They underpin coastal fisheries, helping sustain the seafood industry. They also absorb enormous amounts of pollution and help sequester planet-warming gases. A recent study valued these benefits at roughly $500 billion a year, worldwide.
Yet for all they are worth, scientists know surprisingly little about kelp forests. Globally, data on how they’re responding to climate change and other threats, such as the spread of non-native species, is incomplete. Conservation efforts — which have been ramping up in recent years, especially on land — have largely overlooked these marine environments.
What biologists do know suggests that many of these forests are in trouble. And a lengthy new review published this week by the United Nations indicates that kelp forests have declined globally. “Kelp have suffered widespread losses across much of their range,” the report states — and climate change stands to make things worse.
The full story, however, is much more complicated.
A spectacular undersea world that we all rely on
Kelp forests have a lot in common with their land-based counterparts. They form three-dimensional structures that provide homes to animals. They often have a canopy. And kelp stalks themselves look a bit like trees: They have root-like anchors, a central structure similar to a trunk, and leaf-like blades.
Yet there are a few key differences. For example, kelp is not a plant but a kind of algae, a group of aquatic organisms in an entirely different kingdom of life (home to things like pond scum and Florida’s red tide). They also grow far faster than trees — as fast as two feet per day, depending on the species.
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Some kelp species, like the giant kelp common off the coast of San Diego, reach the surface to form a canopy. Others top off many feet down, creating an understory. And these forests are quite widespread, covering an area of ocean up to five times greater than that of all coral reefs, according to the new report by the United Nations Environment Programme (UNEP).
These forests support a stunning diversity of life. Kelp blades and anchors (known as holdfasts, the closest thing they have to roots) provide shelter for young fish, a place for adult fish to spawn, and food for invertebrates like urchins and other creatures. One study found that a single stalk of kelp in Norway supported roughly 80,000 organisms across 70 distinct species. Over 1,000 species of plants and animals are found in some kelp forests in California.
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United Nations Environment Programme
This is especially relevant for people who eat seafood. Research has demonstrated that many popular commercial species including pollack, lobster, and abalone spend at least part of their lives in kelp forests and depend on their existence. A new study in the journal Nature illustrates just how valuable these environments are to the seafood industry: A single hectare of forest contributes an average of roughly $30,000 a year to fisheries, the authors found.
The benefits don’t stop there! As they grow, kelp forests, like those on land, absorb a lot of pollution including fertilizer runoff from farmland and compounds of carbon (much of which enters the ocean from the atmosphere). They’re helping offset much of our planet-warming emissions, for free. The Nature study, which examined a handful of services that kelp provide, conservatively estimates that these habitats sequester at least 4.9 megatons of carbon from the atmosphere each year. “Pound for pound,” kelp remove as much as (or more) carbon than other ecosystems, such as terrestrial forests or mangroves, the study’s lead author, marine scientist Aaron Eger, told Vox.
Combined, the services provided by kelp forests globally — supporting fisheries, cleaning up pollution, and sequestering carbon — are worth half a trillion dollars a year, the study found. And that doesn’t take into account other potential benefits, such as coastal protection (kelp forests may tamp down waves, helping limit the impact of storms, the UNEP report found).
In short: Kelp help.
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Jennifer Adler
Are kelp forests at risk?
The simple answer is yes.
The most recent global analysis, based on data through 2012, found that global kelp forests are declining on average at a rate of about 1.8 percent per year. A more recent review that only considers long-term data (which is more reliable; kelp forests can vary a lot from year to year) points to a more troubling trend. It finds that more than 60 percent of the kelp forests scientists have studied over a period of 20 years or more have declined.
“On the whole, when we look at kelp forests over a long time period and in temperate latitudes, we’re seeing strong declines,” said Kira Krumhansl, a marine ecologist who led the global analysis and was a co-author of the more recent review. Those declines are most severe in regions closer to the equator where the water is warmer, such as Baja California, Western Australia, and southern New England, said Krumhansl, who works at Fisheries and Oceans Canada.
This pattern points to a major force behind shrinking kelp forests: climate change.
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Kelp like to grow in cold, nutrient-rich water, yet rising global temperatures — fueled by power plants, gas-powered cars, and so on — are making the oceans warmer and fueling epic marine heat waves. That has pushed some kelp forests past their thermal limits, especially if they’re already in the warmer reaches of their range.
An added twist is that warm waters tend to hold fewer nutrients, which makes it harder for forests to grow, according to Byrnes, the biologist at UMass Boston.
Another reason why kelp forests have declined is overfishing and the loss of marine predators. Cod, lobster, and sea otters, among other animals, prey on sea urchins. Urchins, in turn, graze on kelp. When fishing nets capture urchin predators, urchins proliferate and mow down kelp forests.
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This process can create what are called urchin barrens, eerie stretches of sea floor covered in little more than prickly orbs. You can find these barrens all over the world, from California to Tasmania to Japan. (Degraded kelp forests are also increasingly being replaced by mats of algae that form a turf on the sea floor and prevent the kelp from recovering.)
Two things that make the story of kelp more complicated
Although research shows that, on average, kelp forests are declining worldwide, some marine biologists are hesitant to make sweeping conclusions about the global trend.
One reason why is that kelp forests vary dramatically from place to place. Many forests have eroded or vanished entirely, though some seem to be fine or are even expanding. “Every spot on Earth has a different story,” said Tom Bell, a marine scientist at the Woods Hole Oceanographic Institution.
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A recent study co-authored by Bell documented steep declines in kelp forests along the West Coast, following a spate of intense marine heat waves between 2014 and 2016. While forests in parts of Northern and Central California have yet to recover these losses, some of those off the coast of Oregon have grown substantially.
“In some locations, we found jaw-dropping recovery in canopy-forming kelps,” said Vienna Saccomanno, a co-author of the recent study and ocean scientist at The Nature Conservancy, an environmental group. “These places are important glimmers of hope.”
Kelp forests also appear to be growing in parts of the Arctic. The ocean there is warming, making the water more tolerable for kelp (yet still cold enough for these algae to survive). Melting ice, meanwhile, frees up space for forests to take root. But this trend is not universal or well understood. Melting ice can also make the water cloudier, potentially limiting the growth of kelp forests.
Some parts of the ocean, including the coast of South Africa, are also anomalously cooling, causing kelp forests to increase, Byrnes said.
The other barrier to describing clear trends in kelp forests is a lack of data. Much of the planet’s kelp forests have yet to be mapped, and they’re rarely monitored, according to UNEP. The 2016 global analysis — which remains the most comprehensive assessment to date — only analyzed data for about a third of the regions home to kelp forests. Information is especially limited in places like the tip of South America and in parts of Africa, Byrnes said.
“The lack of information about certain parts of the world really worries me,” Byrnes said. “We don’t know what’s happening. And sometimes it can be alarming.”
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Kelp forests are harder to monitor than most other ecosystems. Often, marine biologists get in the water and count kelp stands by hand, which is expensive, labor intensive, and requires some special skills. Kelp forests can extend for miles.
“It is a challenge to monitor [kelp forests], and that’s partly why they haven’t been as much of a focus for conservation or engagement,” Krumhansl said. “Nobody actually sees them. They’re not like a forest on land that you can walk through and see the changes happening for yourself.”
To an extent, tech is helping fix this problem. Instead of diving into a forest, scientists can now analyze images of the ocean taken by satellites for subtle changes in color that correspond to kelp forest canopies.
Bell’s recent analysis was based entirely on this approach. He used satellite-based data from Kelpwatch, a website he and other scientists designed to make this kind of data freely accessible. (You can do a similar analysis yourself on the website, though for now there’s only data for the west coast of North America.)
There’s one big caveat to this new era of kelp forest monitoring: Satellites, at least for now, can only detect canopy-forming kelp. And just a portion of kelp species form canopies, Byrnes said. That means we may not have a clear picture of these habitats for decades.
The future of kelp forests
In the years to come, kelp forests may still face a raft of problems including overfishing and the spread of invasive species. But none are likely to be more threatening to their long-term existence than climate change.
The oceans are warming, and marine heat waves — extended periods of abnormally hot temperatures — are almost certainly becoming more common. Since the 1980s, the frequency of marine heat waves has doubled, according to a 2021 report by the Intergovernmental Panel on Climate Change, a UN group that studies warming.
That’s a problem for kelp, Krumhansl said. “They are cold-adapted species,” she said. “So the future doesn’t look great.”
Yet there are things that countries and environmental advocates can do to lessen the damage and give kelp forests a chance at survival.
One approach is to protect kelp forests with marine parks. Right now, these ecosystems are underrepresented in the world’s network of protected areas, according to UNEP, yet they’ve been shown to help kelp forests recover. By safeguarding marine predators, such as lobsters and sea otters, parks can keep urchin populations under control.
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Another approach is to manually remove urchins from a reef — an activity that is oddly satisfying to watch — or kill them en masse with poison, which can be highly effective in restoring kelp forests, according to a recent review. (There are plenty of other approaches to kelp forest restoration and an entire organization working toward that cause.)
The good news is that when you take away some of these threats, kelp forests can quickly bounce back, Byrnes said. Kelp is resilient. And again, it grows incredibly quickly. “Kelp is just phenomenal,” Byrnes said. “As long as the conditions are right, it will grow and it will thrive.”