Researchers at the University of Cambridge shocked many of us last month by suggesting we may be closer than we think to the extinction of the human species. The existential threat is not only climate change but also knock-on effects ranging from famine to deadly disease vectors, financial collapse, and resource wars.

The Cambridge paper is not the first to warn us about this accelerating disaster. Five years ago, researchers warned we were 20 years away from the mass extinction of species, the sixth such event in Earth's history. As many as half of the animals on Earth are already gone, the researchers reported.

Climate change is not the only threat. Several years ago, experts organized by the Stockholm Resilience Center identified nine "planetary boundaries" that human civilization can't cross without jeopardizing the Earth's "safe operating space."

Geologists think we have entered a new epoch in which humankind is the most powerful force on the planet, and not in a good way. A committee charged with investigating this concluded we have "profoundly altered the Earth" with "abrupt anthropogenic perturbations" of the natural cycles, and some will last millennia or more. The committee's proposal to name the new epoch the Anthropocene is working its way up to the international group of renowned geologists who will make the final decision.

These findings show we humans are the planet's most invasive species. The United Nations is trying to correct that with some of its sustainable development goals, and so is the rest of the world under the UN's Framework Convention on Climate Change.

However, the tendency is to assume that new technologies can save us when the real solution is more subtle. Yes, we must replace old energy with new energy, but we must also replace human hubris with humility. We are not only the most powerful force on the planet but also the most destructive. We comprise only 0.01 percent of life on the planet among 8.7 other species, most yet to be discovered. Their survival depends on us, but ours depends on theirs.

Even that acknowledgment is not enough. Our moral responsibility extends vertically to other humans and species. It also extends vertically to past generations for what they have given us and future generations that depend on what we will leave them.

This concern for the future assumes we have one, but many of the world's people are no longer sure. In a survey seven years ago, 54 percent of respondents said they believed there was only a 50-50 chance the West's way of life would last beyond the next 100 years. One in four respondents thought the odds their way of life would endure were less than 50 percent.

Nearly 80 percent agreed that "we need to transform our way of life if we are to create a better future for the world." I find some positive signs in the recognition that we must change our behaviors rather than merely changing our technology.

Technology's costs

The two political parties in the United States don't agree on much, but they do believe that innovation is the way to stop climate change. Innovation is the path of least political resistance to the future. It's much easier than telling people to change their values and behaviors.

The allure of the technical fix is strong among international leaders, too. Many are convinced that two technologies, in particular, are indispensable for stabilizing the climate. The first is carbon capture and sequestration (CCS); the second is Direct Air Capture (DAC).

CCS would separate the principal global-warming gas, carbon dioxide (CO2), from the exhausts of power plants and industrial facilities. An energy-intensive process would turn the gas into a liquid for transportation to sites for injection into deep geological formations.

The U.S. Department of Energy has spent billions of taxpayer dollars to research and demonstrate CCS since 1997, but the investment has produced more failures than successes, and CCS remains too expensive for widespread commercial use. If it does become viable, it is expected to double the price of electricity while the costs of solar, wind and water power are much less since those renewable resources are free.

In theory, DAC would remove CO2 from the air to bring the atmospheric concentration of the gas down to safe levels, ideally from 420 parts per million (ppm) today to the 350 ppm considered safe. Nineteen DAC installations are operating today, removing CO2 at between $250 and $600 a ton. DOE is spending billions more dollars, hoping to bring the cost down to $100 per ton.

But two prominent energy experts in America – Morey Wolfson, a former energy advisor to two Colorado governors, and Dr. Kevin Trenberth at the National Center for Atmospheric Research -- have run the numbers, and they don't look good. One ppm of CO2 by volume is about 7.8 billion metric tons. Even at $100 a metric ton, lowering the atmosphere's carbon concentration by just one ppm would cost $780 billion. If we stopped emitting CO2 today, getting back to 350 ppm would cost nearly $55 trillion. Unfortunately, we haven't stopped emissions, the world's population is growing, and billions of people want to move out of poverty.

No one has identified who would pay for DAC, although taxpayers and customers usually bear the brunt of higher energy prices. However, a less expensive and more effective approach would be to rally the global grassroots to get directly involved than now in an ambitious campaign to deploy renewable energy, energy efficiency, and intelligent land use practices.

Land use changes

Oceans, soils, vegetation, wetlands, and forests are among the natural "sinks" that absorb and store CO2. They are nature's DAC. Research published by America's National Academy of Sciences in May concludes that 12 percent of the world's soils and plants offer unrealized potential to sequester CO2.

However, the authors excluded the sequestration potential of agricultural and urban lands, apparently assuming they are otherwise occupied. However, both belong in the sequestration equation. One study determined that human-caused emissions from less-than-optimal farming and soil management practices account for nearly 14 percent of anthropogenic CO2, primarily because of soil erosion. But CCS would be able to capture only 5 percent of human CO2 emissions in the next 40 years, while intelligent land management can capture carbon at one-seventh the cost, according to research from Mexico State University.

In addition, soil-based CCS provides multiple bonuses ranging from improved soil fertility and better soil water retention to healthier grasslands and habitats for wildlife, including pollinators.

These land-use changes have taken a back seat to technological approaches in the Paris climate agreement. A review of the climate-action plans submitted to the United Nations by 167 countries found in 2019 that guidelines for land-use changes were scarce in the Paris process, and only 11 nations submitted fully quantifiable and-use plans.

Energy efficiency

The cleanest and least-expensive energy is the stuff we don't use. The American Council for an Energy Efficient Economy (ACEEE) scores countries on their efficiency efforts. It concluded this year that "energy efficiency remains massively underutilized globally despite its proven multiple benefits and its potential to achieve significant reductions in emissions by 2040." ACEEE calculates that greater energy efficiency in transportation, buildings, and industry in the United States, for example, could cut its greenhouse gas emissions by 50 percent by mid-century.

The International Energy Agency (IEA) concluded earlier this year that doubling the rate of improvement in global energy intensity (the amount of energy to produce a dollar of GDP) would save as much energy as China uses in a year and achieve a third of the global emission reductions necessary in this decade. The IEA is even more bullish, estimating that energy efficiency could prevent enough greenhouse gas emissions to achieve 40 percent of the reductions called for in the Paris accord.

Renewable energy

About 80 percent of the world's energy is supplied by fossil fuels today. The International Renewable Energy Agency (IRENA) estimates we could keep global warming well below 2oC if renewable resources provided 65 percent of the world's primary energy and 80 percent of its electricity by mid-century. Some analysts calculate renewables could provide all of the world's energy in the next 30 years or less.

IRENA says this energy transformation would pay for itself. By 2050, it would produce $19 trillion in economic growth, support 26 million jobs, and reduce public health hazards and environmental damages. Combined with energy efficiency and a global investment of $830 billion annually by 2050 (less than 4 percent of world military spending in 2019), renewables could achieve 90 percent of the decarbonization envisioned in the Paris accord, while other low-carbon solutions provide the rest, IRENA says.

Conclusion

One of the most important benefits of these approaches is that they engage people in the fight against climate change rather than jobbing it out to technologies. Personal engagement is probably the best way to counter climate negativity and despair. It can change how people relate to nature and foster a sense of accountability for how we live our lives.

Advances in technology also are indispensable if they are the right technologies. Affordable battery storage, better wind turbines, more efficient solar panels, green concrete and steel, methods to recycle retired renewable energy equipment – these are the technological advances we should be after. They empower the right behavior rather than continuing to make messes and pay for machines to clean them up.