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How Climate Change Was Won

sun appears on a planet's horizon, illustration


November 14, 2170: A special report from Hervé Ngambé, science correspondent, The Chronicle Times, Schenkel station, Mare Erythraeum, Mars

The U.S. National Oceanic and Atmospheric Administration (NOAA) announced today that for the first time since 1988, atmospheric CO2 levels dipped below 350 parts per million. While few watch these figures now, historical records show this reality seemed impossible when humanity began taking climate change seriously in the 2020s. Thanks to some forward-thinking individuals and organizations, humanity largely avoided the worst-case 21st century predictions for weather, sea-level rise, and other catastrophes. This retrospective examines how the climate change war was won.

In the early 2020s, industry experts predicted it could take 100 years or longer—at an incalculable cost—to replace the fossil fuel infrastructure, and even then, deep decarbonization was not a guaranteed outcome. In the wealthiest countries, decoupling economies from fossil fuels required uncountable changes, while in the then-poor countries, population urbanization drove economic growth, quality of life, and energy use. Between 2020 and 2040, CO2 emissions increased 26%, almost exactly the 28% predicted by the energy industry. Temperatures rose, and arctic and Antarctic ice continued to melt.

Emissions from energy production were the root of the problem, but energy system changes—including emission caps, high carbon taxes, and fuel embargoes—proved very difficult. Added to the energy challenge, scientists on the International Panel on Climate Change determined that more than a thousand-billion tons of CO2 in the atmosphere and oceans had to be removed to achieve climate goals. "Climate anxiety" affected an entire generation. Despite protests and a multitude of grassroots and policy efforts, it was unclear how any individual or small group could affect large-scale systemic change. However, according to the annals of science, that is exactly what occurred.

In 2025, small collections of philanthropically funded research efforts in the fields of genetics, chemistry, physics, materials science, computing, and theoretical and experimental nuclear physics were asking the right questions. The 2029 Quantum Computing Revolution offered new tools for solving key problems they had identified, and the rest was history. The fruits of that pre-mainstream science investment grew into our prosperous yet low-environmental-impact economies, custom-genetics benefiting disease management and carbon-sequestration, and today's modern power sources.

The success pattern for these key research innovations included a potent combination of asking researchers the right questions combined with philanthropic funding of early-stage, cross-disciplinary science. Some truly interesting initial outcomes spurred mainstream government research funding, followed by public-private partnerships for development. Policy support helped drive economies of scale, and successes continued to materialize. The deployment of these new technologies at immense scale prosecuted the war on climate change over 130 years on three key fronts: reduced weather extremes, lower CO2 levels in the atmosphere, and carbon-free energy.

Weather extremes in 2036 decimated crops in South Australia, central California, and Fujian, followed by the "thousand-year" storms of 2038/2039 that wiped out New Orleans, Venice, parts of Bangladesh, and coastal Florida, along with a number of islands—including some belonging to technology billionaires. These crises triggered the adoption of the 2040 UN "Venice Accord" protocols, which allowed large-scale deployment of irradiance modification techniques, including low-impact chemical seeds for clouds and plankton-generated polymer mini-bubbles for the ocean surface. By 2058, planetary albedo control was achieved, after which temperature extremes and storms became less severe. While these practices ended many decades ago, they addressed the most urgent weather crises at the time.

The concept of carbon sequestration first appeared in the scientific literature in the 1990's, but it wasn't until 2033 that a breakthrough in quantum gene and protein modeling combined with advanced biotechnology yielded CarboPlankton. These microorganisms sequestered carbon with minimal industrial support. The UN Venice Accord allowed their staged deployment, and sequestration ramped to more than 20 gigatons CO2 annually. The added biological activity combined with other efforts restored Earth's oceans and fisheries to a vitality not seen in almost two centuries. According to NOAA, peak carbon occurred in 2113 at 490ppm. CarboPlankton are estimated to have, over the last 130 years, sequestered a total of 1,800 gigatons of CO2 to the deep ocean floor as a few millimeters of harmless, indigestible organic matter.

Thanks to some forward-thinking individuals and organizations, humanity largely avoided the worst-case 21st century predictions for weather, sea-level rise, and other catastrophes.

Carbon-free energy proved to be a series of battles in this war. In the 2020s, the promise of wind turbines and solar panels drove deployments and helped a handful of wealthy countries partly decarbonize electricity. Still, in the 2050s, methane power plants remained a necessity for many electric grids, and large sectors of industry, agriculture, and transportation remained dependent on fossil fuels. Many of the aging 1960s technology nuclear plants were shutting down, leaving people to wonder what would be done about their waste. Fortunately, some of those 2020s research investments paid off, successively rolling out advanced fission, fusion, and nuclear excitation that completed society's decarbonization.

In the mid 2030s, advanced, lower-cost fission power plants began deployment. Over three decades, several nations significantly reduced dependence on fossil methane and coal power plants. A collection of advanced fission plants recycled almost all the nuclear waste and nuclear bomb material. The most toxic nuclear waste, then thought to last forever, was first transmuted by nuclear excitation in 2032, and by 2060 virtually all of it was gone. The 20th century U.S. nuclear waste fund helped advanced fission energy and waste transmutation achieve initial economies of scale, and the world was rid of two scourges.

Fusion power plants, considered truly futuristic at the start of the 21st century, were enthusiastically adopted in the 2040s. They were a massive boon to deep international decarbonization of the electrical sector. Like fission plants, though, their size and weight were still too large for most transportation or industrial applications. That all changed in 2052 with the Nobel prize for the development of powerpacks—integrated atomic power packages. They were the energy equivalent of the 20th century's integrated circuit, a combination of electrons, laser pulses, and phase-conjugate neutrinos to excite targeted nuclei in a lattice. The resulting waste-free reactions released energy that could be directly extracted as electric power. Powerpacks in different sizes gradually re-powered surface transport, aviation, industry, and now even wearable devices. By 2127, fossil energy had almost no remaining markets.

The war on climate change was won as a result of many efforts, both large and small, but took a markedly different path from that envisioned in the 2020s. Key innovations led to scalable solutions first for weather, then carbon sequestration, and, over different phases, for energy. Addressing key problems from the past opened doors to our future. As this reporter looks out the window this evening to contemplate the distant spot that is Earth, it is humbling to connect these events of the past to our present: the space transport systems that got us here to Mars, the powerpacks in our outposts, rovers and atmospheric suits, and our life-giving transformation of the Martian atmosphere today.

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Ross Koningstein was the first director of Engineering at Google. Over the last few years, he founded nuclear energy R&D at Google and co-founded Google's carbon-aware computing effort.

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More online: Watch the online report from science correspondent Hervé Ngambé at

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