Stephen Hawking Is Worried About Humanity’s Future

Stephen Hawking turns space explorer in his second-ever episode of “Favorite Places,” an Emmy-winning series that sees the famed physicist explore Venus, the sun and deep space.

Hawking narrates the CGI-heavy episode, which premieres on today (Jan. 8). In the episode, Hawking is piloting a spacecraft past his childhood vacation spot in Dorset, England, expounding on his search for the “theory of everything” — an understanding of humanity’s place in the universe and why the laws of physics seem so precisely tuned to support life in the solar system.

“It’s these fundamental mysteries that drive me on my quest for a theory of everything,” Hawking says. [8 Shocking Things We Learned From Stephen Hawking’s Book]

The episode takes Hawking to his favorite places. First Dorset, where he spent childhood summers searching for fossils; then Venus, where the atmosphere is so hot and under such pressure that near the surface, it isn’t a gas but a supercritical fluid. Venus is an example of runaway greenhouse warming, Hawking says, something that could happen on Earth if carbon dioxide and other greenhouse gases in the atmosphere reach extreme levels.

Venus may have been a much more welcoming place about 4 billion years ago, according to NASA. Astronomers believe the planet once had liquid water but underwent a period of runaway warming that burned off the oceans and pushed the temperature of the surface to 864 degrees Fahrenheit (462 degrees Celsius). As water vapor from the planet’s warming oceans amassed in the atmosphere, it likely trapped ever more heat, according to a 2002 NASA study, creating a positive feedback cycle. Venus illustrates the importance of small differences in determining whether a planet can support complex life, according to Hawking, and demonstrates the reality of the greenhouse effect.

“Next time you meet a climate change denier, tell them to take a trip to Venus,” Hawking says. “I will pay the fare.”

Hawking’s fantastical journey soon takes him to the surface of the sun, where viewers hear a simulation of the sun’s “heartbeat,” or the noise of its nuclear fusion. He then visits deep space to witness the birth of a star, based on Hubble telescope imagery from the 1990s. The raw material for this creation comes from the remnants of ancient giant stars, Hawking says.

“In order for a sun and planets like ours to be born, an entire generation of giant stars had to live and die before them,” he says. “And here is a remarkable thing: It takes around 7 billion years for that to happen. Our sun is just over 4.5 billion years old and the universe is only 13.7 billion. So, you and I came into existence at precisely the time it became possible, and not a moment later.”

It seems miraculous, Hawking says, but attributing it to miracles makes it unknowable, and he needs to know. He’s now supporting a new project called “Breakthrough Starshot,” which aims to use nano-size spacecraft, traveling 100 million mph (160 million km/h), to explore the far reaches of the universe. The first planned destination for these tiny spacecraft is Hawking’s last favorite place in the episode: Proxima Centauri, a star in the Alpha Centauri system, where the physicist finds more warnings of intelligent life’s ability to destroy itself.

Benefits of Climate Action

Climate change is one of the most urgent issues of our day. Several recent studies show that acting quickly and decisively to address this challenge and shift our economy to clean energy will bring significant benefits to the United States—while also helping us avoid some of the worst consequences of unchecked global warming.

Congress has begun the historic process of enacting legislation to reduce global warming emissions and transition the United States to a clean energy economy. To be most effective, such legislation should
  • put the nation on a path to cutting emissions by at least 80 percent by 2050 and require significant reductions in the near term as well
  • be comprehensive, combining a cap on carbon emissions with crucial policies that help us shift to more efficient and cleaner forms of energy and transportation
  • protect tropical forests and fund adaptation to climate change

Conserving Water Resources and Clean Water

The IPCC has concluded with high confidence that, by mid-century, precipitation changes owing to climate change will mean that less water will be available in already arid parts of the world, including the western United States. Climate change is contributing to snowpack losses and melting glaciers in the United States, leading to water shortages in the West. Addressing global warming could lessen the threat to these water resources.

Water shortages have wide-ranging consequences. For example, as sources of water used for irrigation dry up, the costs of producing food could rise. Lower water levels and higher temperatures in streams and rivers could diminish the capacity of hydropower and cause the collapse of some fisheries. And water prices could rise not only for farmers but also for industry and homeowners, especially in areas where growing populations are already putting stress on water resources, such as the southwest United States. Finally, because the concentration of pollutants increases when water levels drop, water shortfalls could also lower water quality.

An important note is that nuclear power and fossil fuel plants that produce electricity rely on vast quantities of water for cooling, while many climate-friendly renewable sources (excluding conventional biofuels) require far less water, leaving more for other purposes and making them better suited to a climate constrained world.

Preserving Vital Ecosystems and Species

Addressing global warming could help lessen the harm to ecosystems that now provide us with multiple benefits. For example, rising seas threaten coastal barrier reefs, which protect communities from storm surges, and wetlands, which filter impurities from water. Drought and pests threaten forests, which provide lumber. Warming temperatures and growing acidification threaten oceans, lakes, and rivers, which sustain our fisheries. Because nature does not charge market prices for these services, we tend to greatly undervalue them.

Moreover, many animal and plant species that provide us with important medicines and other products—in addition to having intrinsic value—could face extinction. According to the Nobel prize–winning Intergovernmental Panel on Climate Change (IPCC), if global temperatures rise more than 3˚–5˚F, up to 30 percent of plant and animal species could become extinct. Many projections suggest that the low end of that temperature range could be breached by mid-century. While we cannot avoid some of these harms, lowering our emissions quickly would give us a chance to diminish them.

Delivering Benefits to Low-income Households

Using energy more efficiently and reducing global warming emissions would help all families—especially low-income families—lower their energy bills. The Congressional Budget Office estimates that ACES would help households with income in the lowest fifth of the U.S. income distribution save $40 each year by 2020. The bill would also provide monthly cash refunds and annual tax credits to low-income individuals. The burgeoning clean energy economy could also be an important source of jobs for disadvantaged workers in inner cities and Rust Belt towns.

Low-income communities will bear a disproportionate share of the impact of climate change and have fewer resources to cope. Poorer populations are more likely to lack health insurance, and in urban areas are disproportionately exposed to ground-level ozone and airborne allergens, increasing the incidence of asthma and other respiratory diseases. The poor in coastal and low-lying areas are also less likely to have insurance against losses from hurricanes and floods, and may be less able to relocate if necessary. In addition, one study found that nearly twice as many people of color as the general population lack access to air conditioning, which could lead to more heat-related illnesses and deaths. A warming climate would worsen these conditions, while lowering emissions can lessen their impact on low-income families.

Providing Benefits to Farmers

The U.S. Department of Agriculture estimates that ACES would lead to very modest costs for the agricultural sector in the short term, but potentially significant net benefits over the medium to long term from the growing market for agricultural “offsets.” Instead of directly reducing their own emissions, industries subject to a cap on global warming emissions would pay farmers and ranchers to increase the amount of carbon stored in soils and vegetation, reduce methane emissions from animal waste, or reduce nitrous oxide emissions from fertilizer use. These payments would equal about $1 billion per year from 2015 to 2020, and $15–$20 billion per year from 2040 to 2050.

Farmers can also make money by installing wind turbines, solar panels, and other clean energy technologies on their land and buildings. By leasing land for one utility-scale wind turbine, for instance, a farmer could earn $3,000 a year. The U.S. Department of Energy estimates that, over the next two decades, U.S. farmers and rural landowners could earn $1.2 billion in new income through such steps.

By addressing global warming, we can also help farmers avoid the most severe consequences of climate change. Under an unchecked-emissions scenario, many farmers could face more frequent heavy rains and flooding in the spring, which delay planting; expanded ranges of agricultural pests; and rising temperatures, which stress plants and livestock and reduce yields. Each of these effects can significantly raise costs. And while agriculture in some parts of the country could benefit from warmer temperatures in the short run, eventually most areas would see costs. Some degree of adaptation may be possible—such as by changing crop types, planting dates, and irrigation and fertilizer practices; investing in livestock cooling systems; and taking advantage of crop insurance programs—but these adaptations, too, will likely come at considerable cost.

Enhancing National and Global Security

Top military officials have warned for years that climate change could have serious ramifications for our nation’s security and increase the stress on our armed forces. Drought, extreme weather events, changes in food production, and pandemics caused by climate change could drive resource conflicts and migrations in vulnerable parts of the world. These stresses have the potential to act as “threat multipliers,” raising the number of failed states. The U.S. military may be called upon to respond to humanitarian disasters in these regions; moreover, state failure often exacerbates extremism and terrorist activities, further increasing the burden on overstretched U.S. troops.

Addressing global warming would also reduce the nation’s reliance on oil, including the portion that comes from unstable regimes around the world. UCS estimates that investing in cleaner vehicles and a more efficient transportation system could cut our use of petroleum products by 6 million barrels a day— as much oil as we now import from PEC (the Organization of Petroleum Exporting Countries).

Humanitarian agencies also warn that the world’s poorest people are already bearing the brunt of climate change, and that poorer countries could lose 50 years of development gains if richer nations do nothing.

Saving Households and Businesses Money

A 2009 UCS study found that unleashing the full potential of policies designed to promote efficiency and renewable energy, along with a sharp limit on global warming emissions, would save U.S. households an average of $900 annually by 2030, while businesses would save a total of $126 billion annually. To garner those savings, the nation will need to make some up-front investments—in more efficient appliances, vehicles, heating and cooling systems, and production processes, for example. However, the resulting drops in energy bills from reductions in electricity and fuel use will more than offset the costs of these investments.

Independent analyses of the American Clean Energy and Security Act (ACES), the energy and climate bill now being considered by Congress—such as by the Environmental Protection Agency, the Congressional Budget Office, and the Energy Information Administration (EIA)—show that the act’s costs to the U.S. economy would be minimal. According to the EIA, for example, household energy costs would be less than $10 a month higher in 2020, or less than 33 cents a day, and the total discounted GDP losses from the 2012 to 2030 time period would amount to just 0.2 percent of GDP. And these studies exclude or underestimate important mechanisms for containing these costs, such as greater efficiency, and ignore the savings that would come from avoiding many of the costs of climate change itself.