Some Climate Change Effects May Be Irreversible, U.N. Panel Says

Report highlights human responsibility for heat waves, droughts, intense storms and other extreme weather events. Some Climate Change Effects May Be Irreversible, U.N. Panel Says

Rising seas, melting ice caps and other effects of a warming climate may be irreversible for centuries and are unequivocally driven by greenhouse-gas emissions from human activity, a scientific panel working under the auspices of the United Nations said Monday in a new report.

World leaders—especially those from the West and island nations that are especially vulnerable to climate change—deemed the report a call to action ahead of international climate negotiations scheduled for November. Many called for cutbacks in fossil-fuel consumption, which the report identifies as a leading driver of the rise in levels of heat-trapping greenhouse gases in the atmosphere.

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“The impacts of the climate crisis, from extreme heat to wildfires to intense rainfall and flooding, will only continue to intensify unless we choose another course for ourselves and generations to come,” said U.S. climate envoy John Kerry. “What the world requires now is real action.”

British Prime Minister Boris Johnson singled out the burning of coal, saying the world should “consign (it) to history.”

Issued by the Intergovernmental Panel on Climate Change, an organization of 195 governments, the new report is drawn from a three-year analysis of 14,000 peer-reviewed scientific studies. It is the first major international assessment of climate-change research since 2013.

The report highlights human responsibility for record heat waves, droughts, more intense storms and other extreme weather events seen around the world in recent years.

It also sharpens estimates of how sensitive the climate is to rising atmospheric levels of carbon dioxide and other greenhouse gases—a key metric in forecasting the rise of global temperatures in the years ahead.

“It is unequivocal that human influence has warmed the atmosphere, ocean and land,” the report says in its opening lines. “Human-induced climate change is already affecting many weather and climate extremes in every region across the globe.”

The first of four IPCC reports expected in the next 15 months, the report is likely to be a major force in both geopolitics and business. It sets scientific baselines and offers guidance to negotiators regularly convened by the U.N. under the Paris Climate Agreement, which has become a benchmark for corporate as well as governmental efforts to curb emissions.

The next major climate negotiations, known as COP26 and scheduled to begin in Glasgow on Nov. 1, will bring together representatives from nearly every nation in the world to discuss new, more ambitious commitments for cutting emissions. Mr. Kerry has said the U.S. and other countries must use the talks to speed their efforts because those taken so far are failing to make the progress that scientific research says is necessary within about a decade.

The report ties the types of extreme weather events seen in recent weeks—historic heat waves in the Pacific Northwest, torrential floods in Europe and China, and forest fires in the U.S., Russia and elsewhere—directly to climate change.

“We’ve known for decades that the world is warming, but this report tells us that recent changes in the climate are widespread, rapid and intensifying, unprecedented in thousands of years,” said Ko Barrett, vice chair of the IPCC and the senior adviser for climate at the Office of Oceanic and Atmospheric Research at the National Oceanic and Atmospheric Administration. “Further, it is indisputable that human activities are causing climate change.”

The report “connects the dots in a way we really haven’t seen before,” said climate scientist Michael Mann, director of the Earth System Science Center at Pennsylvania State University, who wasn’t involved with the report. “The message eerily resonates with what we’re seeing this summer in Canada, the U.S. and Europe as extreme weather events play havoc on us and our infrastructure.”

Levels of carbon dioxide released into the air by the burning of fossil fuels, cement production and deforestation and other land-use changes reached a modern seasonal high of 419 parts per million in May. That is higher than at any time in the past 3.6 million years, according to NOAA.

Atmospheric levels of methane, an even more potent greenhouse gas, are now about 2½ times their preindustrial levels and steadily rising, according to the International Energy Agency.

In Glasgow, representatives from almost 200 countries are expected to present updated plans for reducing greenhouse-gas emissions. They are working under a global agreement resulting from the 2015 Paris climate summit that called on nations to take steps to limit future global temperature increases to 1.5 degrees Celsius (2.7 degrees Fahrenheit).

“This report tells us that we probably need even more action by all the major economies to work together to avoid even worse impacts than we’re already seeing now,” said Jane Lubchenco, deputy director for climate and the environment at the White House Office of Science and Technology Policy. She wasn’t involved in the IPCC effort.

Greenhouse-gas emissions from human activity have raised global temperatures by 1.1 degrees Celsius since around 1850, the report said. Without rapid reductions in emissions, global temperatures could rise more than an additional 1.5 degrees Celsius over the next 20 years, the report forecasts.

“We know there is no going back from some changes in the climate system, but some can be slowed or stopped if emissions are reduced,” said NOAA’s Dr. Barrett.

The report reflects new scientific methodologies honed in an era of growing climate disturbances. It draws on a better understanding of the complex dynamics of the changing atmosphere and greater stores of data about climate change dating back millions of years, as well as a more robust set of satellite measurements and more than 50 computer models of climate change.

“We are now much better at integrating all the information,” said Gavin Schmidt, the National Aeronautics and Space Administration’s senior climate adviser and director of the Goddard Institute for Space Sciences in New York, who wasn’t involved with the report.

Last year, global temperatures tied for the warmest on record, capping the warmest decade in modern times. Oceans are warming, and sea level is increasing by 3.7 mm, or about 0.1 inch, a year, the scientists said in the report.

Mountain glaciers, sea ice and polar ice sheets are steadily melting. Weather around the world has grown more extreme by many measures, the scientists said, with more frequent heat waves and prolonged droughts in some regions and heavier rainfall and flooding in others.

“When you see what has happened this summer with heat waves in Canada and the heavy precipitation in Germany, I think this is showing that even highly developed countries are not spared,” said Sonia Seneviratne, a senior scientist at ETH Zurich in Switzerland and a lead co-author of the report. “We don’t really have time to adapt anymore because the change is happening so quickly.”

Major New Climate Report Puts Pressure on COP26 to ‘Consign Coal to History’

The latest assessment from the IPCC is yet another tool negotiators can use to extract more ambitious commitments.

A landmark report by climate scientists released Monday will ratchet up the pressure on world leaders to rapidly end the use of polluting fossil fuels.

The authors warned that time is fast running out to stop global warming from exceeding 1.5º Celsius, the lower end of the temperature targets agreed to in the 2015 Paris Agreement.

The report was signed off on by representatives from United Nations Intergovernmental Panel on Climate Change’s nearly 200 member countries, a roster that includes climate laggards who haven’t yet set targets for lowering emissions that are in line with Paris goals. Few diplomats or leaders from these countries, however, have so far responded publicly to the IPCC’s findings.

One of the few that has spoken up is India, the world’s third-largest emitter. Bhupendra Yadav, India’s environment minister, took to Twitter on Monday to press the case that countries with the greatest historical emissions—mostly wealthier economies in North America and Europe—should carry the largest share of the burden now.

The report, he said, should add force to calls for rich countries to shrink their carbon footprints.

India’s government also reiterated its argument that emissions should be measured on a per capita basis. As India is the second-most populous nation, its emissions per head are extremely low.

Some of the most important readers of the IPCC’s 3,949-page report—or at least the more manageable “summary for policymakers”—will soon be headed to Glasgow, Scotland, for COP26 climate talks, also organized by the UN.

In less than three months’ time, U.K. Prime Minister Boris Johnson will host negotiations aimed at limiting global temperature rise, which is already causing wildfires and flooding around the world.

Countries have agreed to submit new national pledges ramping up their ambition before COP26. At the moment, those voluntary pledges fall far short of keeping temperatures under 2ºC, let alone 1.5ºC, according to the UN.

Johnson urged countries to end the use of coal power, the dirtiest fossil fuel, in order to keep the 1.5ºC limit within reach. “We know what must be done to limit global warming—consign coal to history and shift to clean energy sources, protect nature and provide climate finance for countries on the frontline,” he said on Monday, according to a statement issued by Downing Street.

Coal has been a sticking point in international negotiations meant to smooth the way to a deal in Glasgow. An all-night meeting of Group of 20 ministers last month in Naples, Italy, failed to produce an agreement on phasing out coal power. India was a key holdout.

China, the world’s largest emitter, is also under pressure to announce a roadmap to making deep emissions cuts over the next decade. Its coal consumption is poised to hit a record this year, according to the International Energy Agency. The government in China didn’t immediately respond to the IPCC’s findings.

But it’s not just poorer nations struggling with coal. At a Group of Seven leaders meeting in June, U.S. President Joe Biden resisted a call by European countries to end the use of domestic coal power. In the end, the leaders only agreed to stop financing overseas coal projects.

The IPCC report, which Johnson described as “sobering reading,” concludes that human-made greenhouse gas emissions must be eliminated in order to limit the further global warming—and therefore further damage. “This is physics,” said Valerie Masson-Delmotte, co-chair of the report.

“The only way to limit global warming is to reach net-zero CO₂ emissions at the global scale. The climate we experience in the future depends on our decisions now.”

But the emissions gap remains huge. The IPCC said that 2019 atmospheric CO₂ concentrations were higher than at any time in at least 2 million years.

Speaking after the launch of the report, incoming COP 26 President Alok Sharma warned that even though the world’s desire to keep 1.5ºC within reach is clear, hope is “retreating fast.” G-20 countries must raise their aspirations on climate, he said on Monday, adding that only eight have actually tightened their emissions pledges so far.

“At COP26 we must send a clear market signal to get the transition moving faster,” Sharma said.

Getting emerging economies aligned with basic climate science will require rich countries to deliver on their decade-old pledge to mobilize $100 billion a year in financing to help poor countries invest in green technologies and adapt to rising temperatures and sea levels.

The latest data from the Organisation for Economic Cooperation and Development suggests that climate aid from developed countries amounted to $78.9 billion in 2018, far short of the agreed target.

“Climate negotiations are fragile at the best of times, and ensuring that there is trust in the system is going to be vitally important,” Sharma said.

Saudi Arabia, for instance, has wanted to be seen lately as a facilitator of climate talks, but its former negotiators haven’t always taken on that role.

Tweeting from his personal account, Mohammad Al Sabban, a retired former adviser to the kingdom’s energy ministry who once served as its lead climate negotiator, said that the IPCC’s temperature forecasts were “nonsense” and called the UN group “the center of Climate Mafia.” Al Sabban no longer has an official role, and the Saudi government has yet to comment publicly on the IPCC report.

For vulnerable nations, especially those that have contributed little to historic greenhouse gas emissions, the issue of climate finance is framed around fairness.

“Major emitters must take account for the damages inflicted by the fossil-fuel industry, knowing that every single ton of carbon and every single dollar spent on fossil fuels will have a negative impact,” said Ambassador Diann Black-Layne of Antigua and Barbuda, lead climate negotiator for the Alliance of Small Island States.

While many European countries have increased their climate financing, the U.S. hasn’t kept pace. The Biden administration has pledged $5.7 billion annually beginning in 2024; the European Union, by comparison, provided $24.5 billion in 2019 alone, according to the World Resources Institute.

John Kerry, the U.S. Special Presidential Climate Envoy for Climate, said the IPCC report signaled the need for “real action” in the 2020s. “All major economies must commit to aggressive climate action during this critical decade,” he said.

There’s Already Enough Greenhouse Gas In The Air To Heat The Planet By 1.5°C

The reason why the IPCC’s new report only observed warming of 1.1°C reveals a hidden climate risk—and a powerful solution.

The major new report from the Intergovernmental Panel on Climate Change made headlines around the world on Monday with a dire message: climate change is here, and human choices will determine how bad it gets.

That won’t come as any to surprise to those who’ve been paying even a little bit of attention to conversations around the climate. The IPCC report’s main contribution isn’t its message, but rather the precision with which it’s delivered.

The United Nations-backed scientists now know that humans have, in fact, pumped enough greenhouse gases into the air to warm the planet about 1.5°C. The majority of that warming is tied to two gases—carbon dioxide and methane—that are largely released by fossil-fuel production and use.

And yet observed warming, according to the IPCC, is so far only about 1.1°C. Why is that?

Ironically, the fine-particulate pollution released by those very fossil fuels is masking some of the warming. While greenhouse gases trap sun’s heat in the form of infrared radiation, the particles that cause air pollution—known as aerosols—reflect sunlight back out into space before it reaches the surface of the planet.

If the world gets serious about air pollution or reducing emissions from fossil-fuel use, it will also wind up reducing the amount of aerosols dumped into the atmosphere.

The result would be an improvement in air quality and a reduction in the 9 million or so deaths that can be attributed to air pollution each year. But at least in the short term, the planet would start to warm up as the cooling effect from aerosol pollution disappears.

Fortunately, there’s a way out of this bind. “That is why it’s particularly important to reduce methane emissions in the next 10 years,” says Piers Forster, professor of physical climate change at the University of Leeds and a lead author of the IPCC report.

Methane is a super-warming gas, with 80 times the short-term climate impact of carbon dioxide, and its rise has been tied to the growth of natural gas and cattle agriculture.

That means warming due to the decline of aerosols could be counterbalanced with the rapid, large-scale and sustained reduction in methane emissions.

Climate conundra like this one are more common than you might think. Take trees—planting them would seem to be a pretty straightforward solution to reducing the level of carbon dioxide in the atmosphere.

Except it matters where on the planet you put the trees. At higher latitudes, such as in Russian Siberia or the Canadian Tundra, trees don’t just have a cooling impact by reducing CO₂, they also have a warming impact by absorbing sunlight.

The ideal place to grow forests is around the tropics—exactly where they’re being rapidly destroyed.

Reducing methane emissions might be as close as we come to a near-term climate jailbreak, even if it’s not quite a “Get Out of Jail Free” card.

Bloomberg Green has spent the past several months reporting on large methane leaks around the world. While most of these leaks come from fossil-fuel infrastructure, a large number of them are found in countries like Russia or Turkmenistan where governments aren’t as inclined to help fight climate change as many others.

Similarly, tackling methane emissions from cows is not a trivial problem. Scientists, startups and large meat producers are trying methods from changing their feed to making them wear masks. The solutions aren’t cheap, and they don’t eliminate all the methane cows produce, either.

One bright spot in all this: 1.5°C is a political goal, informed by the work of scientists but ultimately establish by governments.

Ed Hawkins, a professor of climate science at the University of Reading and a IPCC author, cautioned against projecting the urgency of the science onto a rigid numerical goal. There’s much greater flexibility than that.

“Every bit of warming matters,” Hawkins said.

Climate Scientists Reach ‘Unequivocal’ Consensus On Human-Made Warming In Landmark Report

The first major assessment from the UN-backed Intergovernmental Panel on Climate Change in nearly a decade sees no end to rising temperatures before 2050.

An epochal new report from the world’s top climate scientists warns that the planet will warm by 1.5° Celsius in the next two decades without drastic moves to eliminate greenhouse gas pollution.

The finding from the United Nations-backed group throws a key goal of the Paris Agreement into danger as signs of climate change become apparent across every part of the world.

The latest scientific assessment from the UN’s Intergovernmental Panel on Climate Change for the first time speaks with certainty about the total responsibility of human activity for rising temperatures. The scientists forecast no end to warming trends until emissions cease.

“It is unequivocal that human influence has warmed the atmosphere, ocean and land,” wrote the authors of the IPCC’s sixth global science assessment since 1990 and the first released in more than eight years. The crucial warming threshold of 2°C will be “exceeded during the 21st century,” the IPCC authors concluded, without deep emissions cuts “in the coming decades.”

The assessment released on Monday is the work of more than 200 scientists digesting thousands of studies, and an accompanying summary was approved by delegates from 195 countries.

More than any other forecast or record, this report’s determinations establish a powerful global consensus—less than three months before the UN’s COP26 international climate talks.

Among The Headline Findings: The past decade was most likely hotter than any period in the last 125,000 years, when sea levels were as much as 10 meters higher.

Combustion and deforestation have also raised carbon dioxide in the atmosphere higher than it’s been in two million years, according to the report, and agriculture and fossil fuels have contributed to methane and nitrous oxide concentration higher than any point in at least 800,000 years.

The full, 3,949-page assessment was released in conjunction with the 42-page “summary for policymakers.” While the latter went through a diplomatic approval process in addition to a scientific one, the former comes directly from scientists.

Chapter one of the underlying report includes strong language admonishing Paris signatories, calling their pledges so far under the agreement “insufficient to reduce greenhouse gas emission enough” to keep global warming well below 2°C.

The document is “a code red for humanity,” said Antonio Guterres, secretary-general of the United Nations, in prepared remarks tied to the release. “This report must sound a death knell for coal and fossil fuels before they destroy our planet.”

Even as the IPCC authors have done away with some of the cautious uncertainty that marked past assessments, the last few months have seen a series of rapid-fire climate disasters that underline the new language.

Summertime in the Northern Hemisphere has been marred by severe flooding across Europe and China, as well as alarming drought and the early onset of large wildfires in the Western U.S. and Canada.

One of the coldest places on the planet, Siberia, has experienced severe heat and forest fires. Just this past weekend brought disturbing footage of people fleeing sprawling wildfires in Greece.

Nearly all of this can be attributed to human influence. The IPCC found that the combined effects of human activity have already increased the global average temperature by about 1.1°C above the late 19th-century average.

The contribution to global warming of natural factors, such as the sun and volcanoes, is estimated to be close to zero.

In fact, humans have dumped enough greenhouse gas into the atmosphere to heat the planet by 1.5°C, according to the report, but fine-particle pollution from fossil fuels provides a cooling effect that masks some of the impact.

In its fifth assessment, published in 2013, IPCC’s volunteer scientists introduced the idea of a “carbon budget,” setting an upper bound on the amount of carbon dioxide that can be added to the atmosphere before it will breach certain temperature thresholds.

“Now we have much more confidence in those numbers,” said Joeri Rogelj, a lecturer in climate change and the environment at Imperial College London and one of the report’s authors.

Humanity will have about a 50% chance of staying below the 1.5°C threshold called for by the Paris Agreement if CO₂ emissions from 2020 onwards remain below 500 billion tons.

At the current rate of emissions, that carbon budget would be used up in about 13 years. If the rate doesn’t come down, the planet will warm more than 1.5°C.

“Our opportunity to avoid even more catastrophic impacts has an expiration date,” said Helen Mountford, vice president of climate and economics at the World Resources Institute.

“The report implies that this decade is truly our last chance to take the actions necessary to limit temperature rise to 1.5°C. If we collectively fail to rapidly curb greenhouse gas emissions in the 2020s, that goal will slip out of reach.”

The new publication lands in the middle of the ramp-up to COP26, to be held in Glasgow in November. A global deal to pursue faster emission cuts would depend on poor countries securing $100 billion a year in climate finance from rich countries, something envisioned in previous climate agreements but not yet achieved.

National governments would also need to agree to rules governing the trading of emissions permits, to ensure those moving faster towards cuts are rewarded for doing so.

Unlike the IPCC’s somewhat anomalous 2018 special report, Global Warming of 1.5°C, the publication released Monday doesn’t explicitly state that net-zero emissions must be achieved by 2050 to meet the goals set out in the Paris Agreement.

That’s because this group’s mandate was to assess new scientific knowledge, not prescribe policy actions. Upcoming IPCC assessments expected next year in February and March will address climate impacts, adaptation and mitigation.

The authors of the new IPCC publication add that, after accounting for global emissions since the 2018 special release, its estimate of the world’s remaining carbon budget is “of similar magnitude” to the one in its prior publication, implying that the finding stands.

This latest assessment’s most ambitious scenario shows emissions falling to net zero around 2050, which is as close as it comes to restating the top-line conclusion of the special report.

All five of the new report’s temperature scenarios show the 1.5°C marker passed by 2040, before cooling down below that mark in only one of five scenarios. Achieving that cooling will depend on large-scale removal of carbon dioxide from the air.

An independent analysis conducted by the group Climate Action Tracker suggests that current global policies may track either the IPCC’s medium or high scenarios, which lead to 2.7°C and 3.6°C of warming by 2100.

New Scientific Tools Enter The Mainstream

The climate science profession has seen entire specialties emerge and mature in the years since the IPCC’s previous mega-report on science. None of these is more resonant than the ability to analyze extreme weather events in real-time to determine the role of climate change.

Twenty years ago, researchers couldn’t link a specific weather event directly to human-made climate change, meaning that the scientific likelihood of a specific storm or heat wave being tied to warmer temperatures wasn’t knowable.

Today, many of these weather attribution studies can be produced within days or weeks of an event.

The deadly heat wave that gripped the western coast of North America in June had detectable evidence of human responsibility. World Weather Attribution, an international research group, needed just days after the heat broke to conclude that the extraordinary temperatures would be “virtually impossible” without climate change.

This ability of scientists to parse the probability that any one disaster is driven by warming temperatures highlights one of the IPCC’s core findings: The entire globe is warming, although not uniformly. Regions will still experience natural swings in temperature, particularly in coming years, as it takes time for heating to have a significant effect on the Earth’s processes.

Another research breakthrough in the field of climate sensitivity now allows scientists to make even more confident projections about future warming.

Drawing from research on ancient climates, as well as advanced satellite technology that monitors clouds and emissions, IPCC authors were able to narrow their temperature projections for the rest of the century, giving humanity a clearer picture of what lies in store if we don’t act quickly to curtail emissions.

The Earth’s response to a theoretical doubling of preindustrial CO₂ levels is now thought to be between 2.5°C to 4°C—a much smaller range than 1.5°C to 4.5°C in previous IPCC reports.

“The top end is being reduced, which means that some of these really bad outcomes, where we roll sixes on the climate sensitivity dice, seems a little less plausible than they did,” said Zeke Hausfather, director of climate and energy at the Breakthrough Institute, who wasn’t an author of the summary.

This development helped the IPCC authors cope with another headache: Some Earth-system models updated for this assessment began showing surprisingly high projections for future warming.

But the breakthrough allowing greater confidence in the Earth’s potential response to CO₂ gave scientists welcome evidence to balance the modeling approach with other research.

The improvements in projections came, in part, from a stronger grasp of so-called “climate feedbacks” such as the way melting ice and greenhouse gases escaping from thawing permafrost compound on each other in previously unpredictable ways.

Scientists are now more confident that lowering emissions will mean less chance of activating feedbacks. That also means that the actions humanity takes in the near term to limit emissions will be a determining factor in whether we see these dramatically accelerating effects in the longer term.

The IPCC’s new findings rule out the possibility that unrestricted emissions will have only a mild effect on global temperatures, a hope few if any observers were still clinging to.

But the updated science, particularly the narrowed range for climate sensitivity, provides powerful evidence of the world’s best pathway to safety: swiftly ending the release of carbon dioxide and other greenhouse gases.

What Comes Next?

There is an endgame, if nations choose to try and reach it. The data continue to show a straightforward relationship between CO₂ and temperature. That means that when atmospheric carbon concentrations stop rising, the temperature will, too, soon thereafter.

Scientists have broken ground by projecting what happens when our emissions cease. As the world reduces its use of fossil fuels, for instance, the cooling effect of aerosols will start to decline. Scientists are confident that one way to counter that decline would be to pursue “strong, rapid and sustained reductions” in methane emissions.

Beyond CO₂, methane, and nitrous oxide, there are four other greenhouse gases that also provide opportunities to slow warming.

Even at 1.1°C, climate change is taking lives and destroying property and forcing retreat, migration and conflict. The effects of human activity are continuing to melt glaciers and sea ice.

Heating oceans means raising them—at a rate more than 2.5 times faster in this century than the last, according to the IPCC. Some of that harm is now baked in for centuries to come.

“This last year has proven that climate change is no longer a distant threat,” said Katharine Hayhoe, chief scientist at the Nature Conservancy, who wasn’t involved in the summary.

“We can no longer assume that citizens of more affluent and secure countries like Canada, Germany, Japan and the United States will be able to ride-out the worst excesses of a rapidly destabilizing climate, even as those in more vulnerable latitudes suffer.”

In a press conference Monday morning, IPCC leadership emphasized that the disparate effects of climate change are being felt in every region of the world. The new report also comes with an interactive tool that enables users to apply its underlying datasets to the world map.

That could, for example, help India reckon with the impact warming could have on economically crucial rainfall patterns under different emissions scenarios.

“When we put everything together, for almost all of the 44 regions in the world, coastal climate impact drivers were increasing,” said Roshanka Ranasinghe, professor of climate change impacts and coastal risk at the University of Twente and one of the authors of the assessment.

The IPCC is inherently conservative. It emphasizes information in which scientists have the most evidence and agreement. At the same time, the new scientific consensus doesn’t rule out continued investigation of its lower-confidence findings.

The authors indicate that some potentially sweeping changes are not as well understood, such as unlikely but still possible heat extremes or ice-sheet collapse.

Another “low-likelihood high-impact outcome” flagged by IPCC authors is a sudden, dramatic change in ocean circulation. A study released last week in the journal Nature Climate Change documented changes in the powerful churn of Atlantic water as potential indicators of “an almost complete loss of stability.”

The IPCC itself foresees further weakening of the Atlantic Meridional Overturning Circulation in the decades ahead, with disagreement over the possibility of collapse before 2100. Such an event would weaken monsoons in Africa and Asia, strengthen them in the Southern Hemisphere and dry out Europe.

There are always more questions to ask, and the perpetual churn of research means even the most comprehensive assessment can never be truly complete. “That’s just what science is, right?” said Tamsin Edwards, an IPCC author and a reader in climate change at King’s College London.

“It’s constantly evolving and refining and adding new studies, and improving our knowledge. The intensity of the effort that goes into assessing the literature—the 14,000 papers for this report—makes it an authoritative, comprehensive, coherent synthesis in a way that a single paper can never be.”

Where Climate And Covid Migration Converge

Sleepy Humboldt County, on the northern edge of the California coast, is seeing a surge in housing demand that it doesn’t have the infrastructure to accommodate.

Living in Sonoma County, Jane Fusek was constantly haunted by fire. She’d never had her home destroyed, but she’d been evacuated more than once. She watched her brother lose everything in the 2015 Valley Fire, and a friend lose their in-laws to another.

“To live in the community then afterwards, it’s just you constantly — you get reminders of this tragedy over and over again,” she said. After the 2019 Kincade Fire, Fusek reached her breaking point. She was retired, renting alone and dealing with multiple sclerosis.

“I have to really take care of myself,” said Fusek, now 73. “And to live in a place that turns out to be stressful half of the year was not helping at all. I just needed to get out of there and get out of the smoke.”

First she moved to Fort Bragg, a former military outpost on the California coast near where her sister had settled. Then the pandemic hit, housing prices surged, and she was pushed farther north in search of somewhere she could afford to buy a home: Humboldt County.

Home to towering redwoods, lush marijuana fields, swirling fog, Bigfoot rumors and indigenous tribal land, Humboldt County has a deep quietness to it — eerie and peaceful in turn.

As the West contends with climate change, Covid and a housing crunch, the county, located 250 miles north of the farthest edges of the Bay Area, has become a refuge.

But migration has also strained its already limited housing supply, leaving people like Fusek to compete with wealthier Bay Area evacuees who are able to work remotely, and longtime residents who are trying to hold onto their properties.

“We’re seeing the market just act like it never has before,” said Gregg Foster, the executive director of the Redwood Region Economic Development Commission.

“When realtor.com and the Wall Street Journal lists Humboldt County as one of the top 20 hot markets in the nation, you’re just like, what? Us? Are you kidding me?”

The factors that have made other areas in the U.S. more unlivable have only bolstered Humboldt’s appeal. While climate change has brought heat waves to much of the U.S., warming temperatures have made Humboldt milder than it used to be, piercing the once-constant fog and leading to more temperate days.

Its isolated location on the coast and its concentration of old-growth redwoods and native trees make it less vulnerable to fires than its inland neighbors.

But its acres of native forests and its limited accessibility also make it harder for the county to support rapid growth. Houses built with redwood logs are sturdy and old and tend to stay in families for generations.

After years of little turnover or new construction, inventory has stayed low. And now, demand has surged.

“It’s a little bit of everything. It’s just been a housing crisis here for years,” said Brett Watson, the mayor of Arcata, where he moved in 2006. “It’s just gotten more expensive.”

As Humboldt County joins the ranks of regions whose role as a climate haven makes them a target for rising property values, it is also contending with an influx of remote workers who’ve migrated up the coast.

The pandemic-spurred “Zoom Boom” has hit western areas including Lake Tahoe, which straddles California and Nevada; and Missoula, Montana. It has also turned California cities like Sacramento and Stockton into appealing places to start a family. But Humboldt isn’t a resort town, or a Bay Area-adjacent hub.

“We don’t have the infrastructure to accommodate people — short term or long term,” said Annalise von Borstel, a real estate agent based in Eureka, who helped Fusek find her home. After a slowdown during the beginning of the pandemic, things started ramping up in January. By June 2021, “it was just a runaway train,” she said.

Housing costs in Humboldt County leapt more than 16% over the past year, according to Zillow, at $387,575 for a typical home in June 2021; housing prices in Eureka and Arcata, the county’s two largest population centers, grew by 18% and 13%, respectively.

While making homes more unattainable for locals, these prices can seem particularly attractive for Bay Area transplants, for whom buying an average home can easily reach (or top) $1 million.

Fusek started looking for a home in September 2020, and was outbid on a dozen offers before closing on a house in McKinleyville in December, sight unseen.

“I could tell that things were going to just get worse,” she said. “People had somehow discovered Humboldt and they were now just making [cash] offers way over the original asking price. If I had started looking maybe just a few months later, I probably wouldn’t be able to afford it.”

Other factors will soon likely make housing even tighter. Humboldt State University, the largest employer in the area, is planning to increase its technical offerings to become a polytechnic institution.

As part of that designation, it’s poised to receive more than $450 million in investments from the state to build more labs and research capacity, and eventually increase its student population by 6,000 to 8,000 people.

The university has its own plans to add about 2,000 units, but von Borstel says it won’t be enough to house the new students, faculty and staff — and it won’t be built fast enough.

“I know that the president of HSU and [College of the Redwoods] are aware of this issue and are trying to be proactive, but this should have happened years ago. So we’re behind the ball,” she said.

Already, HSU students have had trouble staying in the area after graduation because of the lack of housing and jobs to support them. A large new data center has plans to build and hire up in Arcata, and Google has invested in an undersea fiber optic cable that will connect Eureka and Singapore and lay the groundwork for more tech development.

That’s a mixed blessing for the county, says Foster. “As a community we’re having some success in terms of job growth and new companies,” he said. “And we’re like huh, well, where are we going to put all these people?”

Foster says local businesses have long had trouble matching their workforce needs to the population that can afford to live nearby.

Short-term rental housing has long been in short supply, but with a housing market so hot, some owners are selling properties out from under renters.

“From lower income to higher income levels, we really need housing in all areas of the spectrum,” said Watson, the Arcata mayor.

The region is turning inward to look at creative ways to increase supply. Eureka has been easing its regulations on accessory dwelling units (second apartments on the same lot as single-family homes), which will pave the way for more small-scale construction, says Brandon Brown, a local Remax agent. And residents are starting to open their doors.

Three years ago — before the pandemic and the day Bay Area skies turned orange — Michelle Healy was living in Vallejo, California, when she had a premonition that she and her family had to go north, and that others would be following close behind. So she moved to Arcata, where she renovated two buildings with her family.

One is a craftsman house with two bedrooms, where she lives with her dog, Cooper; the other is a four-unit, two-story building that she rents out.

The units’ walls are made with old growth redwood planks, and native plants bloom in the backyard.

Though she’s gotten requests to rent rooms out to everyone from electric company linemen to film directors, she’s prioritized opening her doors to first responders, offering lodging for those who travel there temporarily to meet the region’s growing essential needs, from fighting fires inland to manning hospital beds.

Her place has been booked for the last two and a half years. Now she’s started connecting with other people in the neighborhood to see if they have any extra rooms.

As California’s current fire season continues to worsen — the month-old Dixie Fire is now the second-largest in state history — Fusek is relieved to be settled where she is.

She doesn’t envision Humboldt ever becoming a booming metropolis, and predicts that some of the Covid transplants who moved in for a season might boomerang back after dealing with the fog and the wind and the remoteness. But she also sees her friends and family who live in high fire risk areas eyeing the drive north more seriously.

“It’s a very, very hard decision for people to make to try to upend yourself,” she said. “But I told them they have a place to come, if they need to get away.”