The Climate Decade: A Global Crisis Unveiled, a Global Movement Unleashed

We've all just lived through a most consequential ten years.

Some decades, like the 1860s for the Civil War and the 1960s for the Civil Rights Movement, are seismic and stand out in history for generations. The 2010s weren't like that (though politically it's been one long mixed-martial arts cage fight) but in this decade, amidst the stampede of everyday life, climate changes, sometimes subtle or invisible, have locked down their profoundly consequential influence on our future-with us, until recently, scarcely noticing.

In the 2010s, more stable climate futures that we could have adapted to were quietly foreclosed on, more dangerous ones that we'll struggle to cope with were inked into the script, and we may, it seems, have stumbled over catastrophic climate thresholds without even knowing.

In this same time, millions have seen the signs and joined the climate fight. Together we've felt grief as bad news mounted, rage as monied interests blocked the world's efforts to save itself and, as climate denial made a political comeback at home, we've felt at times like the mythical Cassandra, cursed to tell the truth and never be believed. And though recent years have brought few clear policy wins and many setbacks, we have also watched clean energy soar to new heights and the youth climate movement surge onto the world stage and we've taken heart.

Members of our Union of Concerned Scientists (UCS) climate team have been reflecting on the last ten years and what really shook us, for better or worse. Below are climate moments, some universal, some personal, that stood out. These are not the only or even the most important ones. But their observations woven together tell the story of a historically consequential decade, when climate change became a climate crisis and in doing so changed us all. Knowing now what we only feared in 2010, many of us would give anything for a do-over, to be our bravest selves before it was widely seen as necessary. But by living these years as we did, millions upon millions of us are meeting the 2020s deeply changed, frightened but fierce, and ready to put it all on the line.

Here's what we've seen. What have you seen? And are you ready for what comes next? We welcome your comments.

2010: A decade is born as a climate policy dies

The decade began at the end of a long, bruising battle for US climate policy. Angela Anderson, Director of the Climate and Energy Program here at UCS, lived this up close. Here's how she tells it:

"The decade opened by dashing the rising hopes that Congress would pass climate policy to guide our emissions downward. After the 2008 midterms, President Obama and the Democratic House majority declared climate a priority and the House passed Waxman-Markey's 1200 page American Clean Energy and Security Act (ACES, H.R. 2454), in part to advance international negotiations toward a climate treaty the US could lead and join in the UN meeting in Copenhagen at the end of 2009. The bill was not enough to deliver an international agreement, leading to the first real collapse of those talks. When ACES went to the Senate, it faced a Republican minority led by Mitch McConnell, who had earlier pledged to block every Obama priority. The Democratic strategy had been to persuade the American people and elected officials to support the bill because of its 'green jobs' and health benefits. One columnist's assessment of that strategy was that, 'It was like "Fight Club"--the first rule to passing climate legislation was that you could not talk about the climate.' So we began the decade with the climate community in disarray, dispirited and directionless. But before too long, we realized that we had to figure out how to help the American public understand how climate is affecting and will continue to affect their lives if we were going to have the political support needed to address what would become a climate crisis."

So, we did our best to dust off, check our discouragement, and get on with the work.

2011: What happens in the Arctic...

The Arctic took a more prominent role over the course of this decade as a key harbinger of climate change. But unlike canaries in coal mines which alert us to danger through harm done to them alone, it has been noted this decade with increasing alarm that "what happens in the Arctic doesn't stay in the Arctic." UCS's Director of Climate Science, Brenda Ekwurzel, has followed these trends for many years. Looking back at the 2010s, she recalls early troubling developments:

"In 2011, the proportion of Arctic sea ice greater than 4 years old--a key indicator of sea ice's resilience--dropped to less than 5% and has never recovered. After dipping to an all-time low in 2012, 7 of the 10 years with the lowest minimum sea ice extent have occurred since. The absence of ice can devastate communities that rely on such ice for food, transportation, and their way of life. On a global scale, disappearing Arctic ice can also contribute to the severe cold snaps and extreme weather we've experienced over the last decade."

More than sea ice has been disappearing from the Arctic this decade. In her work on carbon and boreal forests, our Kendall Fellow, Carly Phillips, has been watching other accelerating changes.

"Arctic permafrost is continuing to thaw and fail at alarming rates. As permafrost thaws, anciently stored carbon can be released to the atmosphere as greenhouse gases, and that, of course, further amplifies warming. Indeed, while the 2011 Arctic Report Card observed 'A major uncertainty is whether continued Arctic warming and permafrost thawing could cause these high latitude ecosystems to become a net source of CO2,' the 2019 Report Card warned that 'Thawing permafrost throughout the Arctic could be releasing an estimated 300-600 million tons of net carbon per year to the atmosphere.'"

2012: Hurricane Sandy's wake-up call

Astrid Caldas, Senior Climate Scientist, recalls when Hurricane Sandy rained destruction, scarred communities, and shaped the climate perception of millions of people from "meh" to "this is dead serious."

"October 29, 2012. It was unreal. Katrina was certainly in my mind as the powerful "superstorm" Sandy blew across the populous, developed Northeast U.S., blowing minds in its wake. I was fortunate to be out of its reach, but I couldn't unglue my eyes from the TV. Nobody in the storm's path had seen anything like it. The images and on-the-ground devastation brought home the realization of what storms could be like in a warming world, of the new, true risks of coastal living, and certainly of the seriousness of climate change (yes, Sandy was made worse by it). Thankfully, Sandy spurred important initiatives like Rebuild by Design that urged us to think big about how to increase resilience; we tried to learn and build back stronger. But since then, warming emissions have kept rising, and Sandy--at the time the second costliest extreme weather event in U.S. history after Katrina--has been surpassed by hurricanes Harvey and Maria in 2017. As we have learned about the role of climate change in making extreme events worse (e.g. here, here, and here), and about the alarming trend in stronger hurricanes, will the US and the world do something about it? How long will coastal communities be able to keep their heads above water, if not?"

2013: CO2 reaches 400 ppm

Climate science tells its story in numbers and in that story, carbon dioxide plays a lead role. Kristina Dahl, Senior Climate Scientist, recalls how in 2013 CO2, invisible to the eye but a potent determinant of the planet's temperature, had the numbers equivalent of a mic drop moment.

"On May 9, 2013, the concentration of carbon dioxide in Earth's atmosphere hit 400 parts per million for the first time in at least three million years. Geologic records suggest that the last time CO2 was at this level was the Pliocene when the Earth was a very different place, e.g., with sea levels roughly 25 meters higher than today. We know from Antarctic ice cores that for the 800,000 years leading up to the Industrial Revolution, the concentration of carbon dioxide in Earth's atmosphere never exceeded 300 parts per million (ppm). When scientists began directly measuring CO2 in 1958, its concentration had risen to 315 ppm. By 1988, when James Hansen testified before Congress that human-induced global warming was detectable and scientists called for sharp reductions in fossil fuel use, CO2 levels were at 350 ppm. Over the next 25 years, those warnings went unheeded as we marched to 400 ppm in 2013. Like Hansen's testimony, the 400 ppm mark could have been a wake-up call to humanity. Instead, we sleepwalked to where we are today: 411 ppm."

2014: Power to the Peoples' Climate Movement

With climate records seeming to fall at an alarming clip by mid-decade and with no real movement on climate policy, many of us working on the issues were desperate for a shot in the arm. As Kate Cell, Manager of our Climate Campaign recalls, 2014 delivered.

"When I first started campaigning for climate action, I was frequently asked: 'What does it take to get us in the streets?' In 2014 the Peoples' Climate Movement answered the question by assembling a huge coalition of climate justice activists, union workers, faith leaders, scientists and health professionals, and thousands more to advocate for climate, jobs, and justice. UCS folks joined more than 300,000 people in a September march in New York City, timed to coincide with that year's UN Climate Summit. Three years later we were one hundred days into the Trump administration's anti-climate, anti-justice, anti-science agenda and it was time to march again. This time UCS didn't just walk. I was privileged to serve on the steering committee that planned the April 2017 mobilization and to organize the attendance of more than 1000 UCS supporters, some of whom also participated in a legislative day to demand action from Capitol Hill. During the march itself, we led the science and health section. I was exhilarated that UCS helped gather 200,000 people in the capital. To all who asked: we're in the streets now and there's no turning us back."

2015: The Paris Agreement

In 2015, we watched in horror as Syrians and other refugees fled crises that, we learned, were exacerbated by climate change. But in a dramatic and hopeful development, the year closed on an historic high note in Paris. No one (perhaps literally) knows these highs and lows better than 28-year veteran of the international climate negotiations and UCS's Director of Strategy and Policy, Alden Meyer.

"On December 14, 2015, the Paris Agreement was adopted, setting a goal of 'holding the increase in the global average temperature to well below 2degC above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5degC above pre-industrial levels,' and requiring countries to put forward self-determined emissions limitation pledges. These initial pledges collectively fell far short of what's needed to meet the temperature goals, so countries were asked to consider "updating" their pledges before finalizing them in 2020. This means that next year is shaping up as the moment of truth for Paris: will countries step up their ambition, or condemn current and future generations to truly devastating climate impacts?

Two days into the next climate summit, held in November 2016 in Marrakech, Morocco, Donald Trump unexpectedly won the U.S. presidential election. At a packed press conference the next morning, I told reporters Trump's presidency would pose a threat to Paris, but also noted the growing numbers of states, cities, companies, and others making strong climate action commitments. In the days that followed, these governors, mayors, and corporate CEOs issued statements pledging to meet the U.S. Paris commitments, despite Trump's election; they now comprise the We Are Still In coalition, which represents more than two-thirds of the U.S. economy and population."

2016: Ecosystems and species pay a price

One of the great injustices of climate change came into clear relief this decade: that people who have contributed least to the problem-the global poor-will pay most dearly for it. Another breathtaking, far-reaching injustice, the climate-driven collapse of whole ecosystems and extinction of species, came into stark focus, too. The Deputy Director of our Climate and Energy Program, Adam Markham, describes the disaster that was unfolding for coral reefs.

"The third-ever global coral bleaching event got underway in 2015 and would play out over the next two years, eventually becoming the most significant event ever documented in geographic extent, length and severity. Warm-water reefs everywhere experienced elevated water temperatures, and by June 2017 70% of the world's coral had been exposed to waters hot enough to cause bleaching. The consequences for Australia's 1,600-mile-long Great Barrier Reef, the world's largest coral reef system, were especially severe. By June 2016, surveys showed that 93% of the corals of the northern section had been affected and that more than 20% had died. The conditions were so extreme that corals such as staghorns suffered catastrophic die-off, altering the species mix and biological structure of the reef. Coral spawning-the mechanism by which reefs can reproduce and recover-was down by nearly 90% on the Great Barrier Reef in 2016 and 2017. The future looks bleak for warm-water coral ecosystems without governments' most ambitious emissions reductions according to both a 2017 UNESCO report and the IPCC's 2018 report, which found that almost all living reefs will be lost if we do not keep warming below 2.0degC."

2017: Hurricanes' unprecedented lashing

The 2010s reshaped our perceptions of the seasons as climate change pushed our normal seasonal cycles to palpably abnormal and destructive extremes. Before giving way to the most extensive wildfire season on record in California, at least until the next year, the 2017 hurricane season landed terribly costly blows, in lives as well as dollars, on Caribbean nations and the U.S.. With family in Puerto Rico, 2017's hurricane season left deep impressions on Climate Vulnerability Social Scientist, Juan Declet-Barreto.

"Seventeen named storms was the balance that 2017 left us. Ten became hurricanes. Six of those were Category 3, 4, or 5, and three made landfall in the U.S. or its territories. No wonder NOAA was glad to declare at the end of November that the 'extremely active 2017 Atlantic hurricane season finally end[ed].' Nowhere in the western hemisphere was that felt with more ferocity, destruction, and misery than in Puerto Rico and the U.S. Virgin Islands. After the near-miss of Hurricane Irma in early September, Puerto Ricans breathed a sigh of relief. But a few weeks later, Hurricane Maria battered the islands, leaving the U.S. territories without power for months and unleashing a humanitarian crisis that contributed to thousands of deaths. Meanwhile, Texas was reeling from Hurricane Harvey, which dropped rainfall that was literally off the charts, prompting NOAA to add more colors to its maps. There, environmental justice communities faced both climate change and acute toxic pollution when structures that house toxic chemicals collapsed due to the rain, exposing residents to toxic emissions. As the decade closes, I wonder about the abysmal difference between the sort of recovery the U.S. Caribbean requires, and what it got: a despondent and bungled federal effort, exemplified by the indecorous spectacle of the President throwing paper towel rolls at victims; plans to continue burning fossil fuels and even bring untested nuclear technologies to the energy grid, instead of a transition to renewables. Still, I am hopeful that Puerto Ricans, wherever they may live, will continue to demand an equitable recovery for our island."

And while all communities hit by extremes wish to be safer, this decade, some began taking aim at those that bear some responsible, as Kathryn Mulvey, Fossil Energy Accountability Campaign Manager, recounts. "Communities across the US began to file lawsuits seeking to hold fossil fuel producers accountable for the mounting costs of climate damages and preparedness. With a majority of Americans thinking that fossil fuel companies should pay for climate damages, these cases are informed by attribution science that quantifies the contributions of particular fossil fuel companies to global average temperature increase, sea level rise, and ocean acidification." Something to watch closely.

2018: Science pulls no punches

Climate scientists can feel like they're howling into the abyss, but things shifted in 2018. This latest year to see a rash of devastating wildfires, hurricanes and other extremes in the U.S. also saw a heightened awareness of and concern for climate change, as Senior Climate Scientist, Rachel Licker recounts.

"Two major climate science reports came out in 2018 that seemed to pack a one-two punch in the public's imagination, quickly giving rise to the terms 'climate crisis' and 'climate emergency.' First came the Intergovernmental Panel on Climate Change's report on Global Warming of 1.5degC. The report made clear that there are dramatic differences for life on Earth between 1.5deg and 2degC warming, let alone anything higher (which is where we're headed). The report also made clear that we don't have a lot of time: to limit warming to 1.5degC, we need to make deep cuts to our emissions in the next decade and achieve net zero emissions by midcentury. Shortly after, and while deadly wildfires roiled California, the Trump Administration released the full Fourth National Climate Assessment (NCA4) on Black Friday in an attempt to bury the report. The strategy backfired, with the report appearing on the cover of major media outlets. NCA4 put a price tag on climate change for the US in a way that wasn't possible before and underscored how the most vulnerable among us are likely to be most affected. Previous reports seemed to go unheard by many. Something was different this time around."

2019: People power, climate justice

Rattled by the weight of 2018's climate science, and with a newfound awareness of the price we are paying for decades of inaction, people around the world rose up by the millions in 2019 to demand a crisis-level response to climate change. Rachel Cleetus, Policy Director for UCS's Climate and Energy Program, who has seen this unfold in her role as an ally to activists, a mother of climate strikers, and herself a protester in the streets, reflects on the surging energy of youth and indigenous movements, the hope and courage they inspire, and their implicit call that hangs in the air: join us, it's your fight too.

"2019 was the year we saw climate protests and strikes take off around the world in record numbers, inspiring us at a time when climate impacts are already so dire and hope so desperately needed. Everyone knows the inimitable Greta Thunberg. Alongside her are many climate justice advocates leading indigenous peoples' movements and youth movements worldwide. They are fighting with a moral clarity that is impossible to deny. Hilda Nakabuye from Uganda was galvanized to action after realizing that climate change was affecting her grandmother's ability to grow food crops. At COP25 in Madrid she spoke powerfully: 'I have come to think that the climate crisis is another form of environmental racism and apartheid.' Indigenous activists like Nemonte Nenquimo, Emergildo Criollo, Sandro Piaguaje, and Taita Pablo Maniguaje, who are part of the Amazon Frontlines movement, are fighting for the future of the Amazon often at great peril to their lives. Chief Raoni Metuktire of the indigenous Brazilian Kayapo people writes: 'We, the peoples of the Amazon, are full of fear. Soon you will be too.' Perhaps some amazing young people in your lives are part of the global strikes for climate justice, putting pressure on political leaders to respond to the climate emergency now. Adults, please support them. Together, we are gaining strength and we will not be denied.

'El pueblo unido jamas sera vencido...The people united will never be defeated!'"