Climate Change Effects on Children: What Must They Witness?

Tenzin Seldon grew up in Dharamsala, India, in the shadow of the Himalayas. In an interview with Tricycle, she described climate change not as an intellectual exercise but as something she lived: she watched the ice-capped mountains above her home melting. Today she is the climate investor proposing Gross Domestic Regeneration as a new way to measure progress. This fall, I watched a recap of her speech at the NAT Gala, where she told that story, and I cried.

I cried because she was describing something a child saw. She did not need a chart to know the world was changing. She watched it happen. And it left me with a question I cannot put down:

This article is my attempt to answer that question the way I have answered hard questions for 28 years: with data, with honesty, and with a system that makes someone act. It covers the climate change effects on children that are already measurable, why children carry the heaviest share, why the world has not treated it as urgent, and what any organization with an ISO management system can do about it this quarter.

What Climate Change Effects on Children Are Already Happening?

Heat: infants face the most dangerous days

The 2025 report of the Lancet Countdown on health and climate change, written by 128 experts, found that infants younger than one year were exposed to 389% more heatwave days each in 2024 than the 1986–2005 average, a record. That is close to five times as many dangerous days in a single generation. Heat-related deaths across all ages now average an estimated 546,000 a year, up 23% since the 1990s.

Infants cannot move themselves out of the heat, cannot ask for water and cannot regulate their body temperature as well as adults. Of all the climate change effects on children, heat is the one that arrives earliest in life, often in the first summer a baby is alive.

School: 1 in 7 students lost classroom time

In January 2025, UNICEF published its first global count of climate-related school disruptions. At least 242 million students in 85 countries had their schooling disrupted by heatwaves, cyclones, floods and storms in 2024. That is at least 1 in 7 students worldwide.

Heatwaves were the biggest cause, affecting over 118 million students in April alone. UNICEF called its own estimates conservative because many disruptions go unreported. Lost school days are one of the quietest climate change effects on children, and one of the longest lasting, because missed learning compounds year after year.

Smoke: wildfires reach the classroom

In January 2025, wildfires in Los Angeles moved from the foothills into dense neighborhoods. A study of 3.7 million Kaiser Permanente members, published in JAMA Health Forum, tracked the surge in respiratory and cardiovascular care during the first week, when smoke was at its worst and Los Angeles County public schools were closed. California’s Office of Environmental Health Hazard Assessment has reviewed the research and found consistent evidence that wildfire smoke harms children’s respiratory health, and its 2026 study found that extreme heat and smoke together have a compounding effect on pediatric emergency visits. Our article on regenerative cities in California shows how those same neighborhoods could be measured and protected.

Worry: children feel it

The largest global study of climate anxiety, published in The Lancet Planetary Health, surveyed 10,000 people aged 16 to 25 in ten countries. Fifty-nine percent were very or extremely worried about climate change, 84% were at least moderately worried, and more than half reported feeling sad, anxious, angry, powerless, helpless and guilty. Three in four said the future is frightening.

Researchers found the distress was linked to a sense that governments were not responding, which makes inaction itself one of the climate change effects on children. Among the climate change effects on children, this one is easy to dismiss and important not to.

Tomorrow: the exposure is set to multiply

UNICEF’s State of the World’s Children report projects that in the 2050s, eight times as many children will be exposed to extreme heatwaves and three times as many to extreme river floods as in the 2000s. Today’s toddlers will be raising their own children in that decade, which means the climate change effects on children we measure now are a preview, not a peak.

Why Are Children Hit Hardest by Climate Change?

Health agencies treat children as a sensitive group for heat and smoke for practical reasons. Their bodies are still developing, they spend more time outdoors and active, and the youngest cannot protect themselves. A heatwave that is uncomfortable for a healthy adult can be dangerous for an infant.

A smoky week that an adult tolerates can trigger an asthma attack in a child. That is why the climate change effects on children show up first in pediatric clinics and school nurses’ offices.

Time is the second reason. A child born this year could live past 2100. Every ton of emissions released now, and every forest lost now, shapes the climate that child will live in for the rest of their life.

The adults making the decisions will not. Climate change effects on children are, by definition, long-term effects.

The third reason is voice. Children cannot vote, invest, sit on a board or sign a permit. The people who will experience the most climate change effects on children have the least power over them. That is why the connection between sustainability, human rights and health matters so much here, and why our article on regenerative health argues that the health of a place and the health of its people cannot be separated.

“If your environmental policy says you will not harm the environment or people, then knowingly exceeding what the science has proven harmful puts you in conflict with your own policy.”
— Diana Lynn, President and Principal ISO Consultant, MSI

Lake Tahoe: When Fire Recovery Raises a New Question for Children

I grew up in Northern California with Lake Tahoe as one of the places that taught me what is worth protecting. So this one is personal.

In 2021, the Caldor Fire burned more than 200,000 acres in and around the Lake Tahoe Basin. Megafires like it are exactly what a hotter, drier climate makes more likely. On March 27, 2026, the Forest Service’s Lake Tahoe Basin Management Unit signed its Caldor Fire Restoration decision, covering roughly 11,100 acres on the south shore.

To prepare burned ground for replanting, the plan allows herbicide treatments, including glyphosate, the main ingredient in Roundup, under an emergency determination. A yearlong Mother Jones investigation reported that the Forest Service had already sprayed glyphosate just outside the basin, including near the base of the Sierra-at-Tahoe ski resort, and that the broader Caldor restoration work authorizes glyphosate across about 75,000 acres of the burn scar.

The basin project boundary surrounds neighborhoods in Meyers and South Lake Tahoe and sits near the headwaters of the Upper Truckee River, the lake’s largest tributary. These are places where children live, hike, ski and swim, so any risk to the watershed belongs in a conversation about climate change effects on children.

What the Forest Service says, and what residents fear

The Forest Service says crews would use backpack sprayers rather than aircraft, keep at least 100 feet from water, post public notices, and that no herbicides will enter Lake Tahoe, a federally protected Outstanding National Resource Water. It has said no herbicide use is expected in the basin project area in 2026 or 2027. Residents, South Lake Tahoe’s mayor and a new coalition, Protect Tahoe, are pushing for a ban rather than a delay. The science on glyphosate itself is disputed: the U.S. EPA says it is not likely to cause cancer when used as directed, while the World Health Organization’s cancer research agency classified it in 2015 as probably carcinogenic to humans.

Why does Lake Tahoe raise the stakes? Because almost nothing leaves it quickly. UC Davis researchers estimate the lake’s water stays in the lake for about 650 years on average. Glyphosate does break down, and studies of streams and ponds have measured half-lives of days to a few months in water.

But it also binds tightly to sediment, its breakdown product AMPA can last longer, and one study found glyphosate’s half-life stretched to 267 days or more in the dark. Lake Tahoe is deep, and much of it is dark. Once a chemical reaches a lake that flushes over centuries, there is no practical way to get it back out. That is what makes prevention the only real control.

I want to be careful here, because credibility matters. As of October 31, 2026, there is no published evidence that the restoration plan has harmed Lake Tahoe or the children who visit it. What there is, is a choice: to answer the damage climate change has already done by adding a chemical whose safety is still disputed, in one of the clearest alpine watersheds on Earth, upstream of the families who live there.

This is where the management system mindset helps. ISO 14001 asks every organization to identify its environmental aspects with a life cycle perspective, to consider pollution levels in its context, and to choose the controls that prevent harm rather than clean it up later. ISO 7101 asks healthcare organizations to plan for the least possible environmental harm.

When manual removal, mulching or other methods can do the job, the precautionary choice protects the children downstream before any harm can occur. It is the same principle I return to again and again: protect before you restore.

What Would Make Climate Change Effects on Children Urgent?

Here is something I have seen in more than 200 audits. Organizations rarely fail because they lack information. They fail because no one decided in advance what information would force action.

A risk register that lists a hazard but never says when it becomes a top priority is a list, not a control. The same is true for a society, and it is why the climate change effects on children keep being reported without being acted on.

Ask yourself what your own organization would do if a hazard affected 1 in 7 of its customers in a single year. It would be the first item at the next management review. It would have an owner, a deadline and a budget. Climate change effects on children have already reached that scale, and in most boardrooms they are not on the agenda at all.

Part of the gap is denial. Much of the world, including some of the most powerful companies in it, still talks about climate change as a debate rather than a measured fact, or makes promises while their own emissions rise. Management systems have an answer for that too.

“Having systems, acting on what the records are reporting, and never letting anyone deny the facts is what prevents good systems from deteriorating.”
— Diana Lynn, President and Principal ISO Consultant, MSI

Courts are starting to write the threshold down. On July 23, 2025, the International Court of Justice delivered its first advisory opinion on climate change. The request began with law students from the Pacific Islands, and the Court unanimously affirmed that states have legal obligations to address climate change, including the obligation to prevent significant harm.

Legal scholars have noted that the opinion recognized that future generations have interests states must account for, even though it stopped short of declaring their rights directly. Young people asked a court to define urgency, and the court took the question seriously.

How Do ISO Standards Address Climate Change Effects on Children?

Since the 2024 climate amendments, climate change has been written into the core of the management system standards. I have verified the clauses below against MSI’s licensed copies. Our article on ISO climate change considerations explains the background.

Every certified organization already has the clauses to manage climate change effects on children. What most lack is the courage to name who the climate change effects fall on. Start with your environmental conditions review, test your emergency preparedness and response procedure against a smoke or heat event, and treat the results as the business risk they are.

The MSI Urgency Threshold Decision Table for Climate Change Effects on Children

Use this table at your next management review. For each row, decide in advance what level of the signal will make it a decision item, write that threshold down, and assign an owner. That is all urgency is. A threshold makes climate change effects on children impossible to postpone.

If your organization wants a structured way to see whether its environmental management system can carry this kind of decision, the free MSI toolkit below is the place to start. It was built for our Gross Domestic Regeneration series, where the social pillar measures exactly what this article is about: whether the people around a place, including children, are better off or worse off because of it.

Why Measuring What We Restore Matters for Children

This is the heart of what moved me about Tenzin Seldon’s work. Under GDP, a wildfire that closes schools and sends children to the emergency room can raise economic output, because rebuilding and treatment are spending. The harm to the child does not appear anywhere. Gross Domestic Regeneration multiplies an ecological, a social and a capital score, so a place cannot look prosperous while its children breathe smoke.

GDR is new and unproven, and our article on alternatives to GDP is honest about why earlier measures stalled. But the direction is right. We protect what we measure, and today almost no economic scoreboard measures climate change effects on children.

If climate change effects on children never appear on the scoreboard, they will never reach the top of the agenda. For a practical starting point at one site, our five regenerative impact metrics include community investment alongside energy, waste and water.

What Can Your Organization Do About Climate Change Effects on Children This Quarter?

In MSI’s 28 years of ISO consulting, with 80+ certifications supported, 200+ audits attended and 600+ professionals trained, I have learned that the most powerful thing a leadership team can do is decide what will make them act before the crisis arrives. Here is a sequence any organization can start this quarter:

1. Watch the big picture first. MSI’s free 16-minute ISO 14001 Executive Brief shows leaders what an environmental management system asks of them.
2. Answer the climate question honestly. Under ISO 9001:2026 4.1 and ISO 14001:2026 4.1, record whether climate change is relevant, and say who it affects, including children in your community and your employees’ families.
3. Name children’s advocates as interested parties. Schools, parents and pediatric health providers near your sites belong in your 4.2 register.
4. Write one urgency threshold. Pick one row from the decision table above and set the level that makes it a management review decision.
5. Score your system. Complete the free GDR-to-EMS Translation Scorecard to see where your EMS is ready and where it is not.
6. Report back. Tell your people and your community what you measured, what you decided and what changed for the climate change effects on children around your sites. Trust is rebuilt one honest report at a time.

Moving to the 2026 editions at the same time? The ISO 14001:2026 Transition course and the free ISO Transition Risk Scorecard help you plan, and our guide to the ISO 14001:2026 management review shows what top management must now consider. For hands-on help, MSI’s ISO consulting team supports organizations through ISO 14001 consulting. Call 760-434-9141 or request a free planning session.

I will keep asking the question Tenzin Seldon’s story put in front of me. I hope you will ask it at your next management review. Our children are already witnessing enough.

The climate change effects on children are no longer a forecast. They are a record.

Climate Change Effects on Children: Frequently Asked Questions

What are the main climate change effects on children?

How many children have had school disrupted by climate change?

Why are children more vulnerable to climate change than adults?

Is climate anxiety in young people real?

Is glyphosate being sprayed at Lake Tahoe?

Do ISO standards require organizations to consider climate change?

What can a business do about climate change effects on children?