Hansen’s Recent Thoughts on Climate Change—and Some History

Saving Earth (June 27, 2019)

Thirty years later, what needs to change in our approach to climate change (June 26, 2018)

Losing Earth: The Decade We Almost Stopped Climate Change (August 1, 2018)

Once one of the few scientific voices crying out about climate change, James Hansen has become a renowned, and sometimes vilified, spokesman. That trek took him more than thirty years, as he documents in a Boston Globe editorial. He’s a controversial figure still—both in his political views and in his opinions on nuclear power (with which I concur; see below)—but to many he is the father of climate change awareness.

A journalistic history of the climate change threat, its people, politics, and science is parsed in Nathaniel Rich’s lengthy New York Times piece, “Losing Earth,” published a year ago. It is a dramatic account in which Hansen is naturally a principal figure. I list it here as essential background reading on Hansen’s role in how the climate issue developed.

I got an early copy of “Saving Earth” forwarded from a friend. It struck me immediately as the most authoritative yet personal view of where the climate change arguments came from and how they need, in Hansen’s singular view, to be implemented.

It’s eleven pages long in pdf form and I doubt most of you will plunge into that. So I’ve excerpted some of the more significant passages.

It is wonderful that more people are waking up to the fact that we have a climate emergency. The emergency was clear more than a decade ago when it was realized that the long-term safe level of atmospheric CO2 was less than 350 ppm. Already, we were well into the dangerous zone. . . .

[The threat of an ungovernable planet] derives mainly from two large-scale climate change impacts. First, low latitudes during the warm seasons could become so hot and inhospitable to human livelihood as to generate an unstoppable drive for emigration. That potential future is emerging into view for regions as populated as India, Bangladesh, Southeast Asia, and huge swaths of Africa. The tragedy would be that these regions are, in a ‘less than 350 ppm climate,’ among the most spectacular and livable regions on the planet.

The second climate impact is sea level rise, which is an ominous threat on multi-decadal time scales. This sea level threat may be less immediate than the low-latitude, over-heating, climate-change threat, but it is more ‘non-linear,’ implying that it has the potential to grow exponentially, becoming unstoppable and irreversible. Note that the sea level threat is near-global, because most of the world’s large cities and infrastructure are located on coastlines. Nations that would be devastated by large sea level rise include the greatest economic powers of the 21st century, the United States and China. These two climate impacts are the heart of the ‘existential threat.’ . . .

Most of the warming still ‘in the pipeline’ is associated with deep-ocean warming. Thus most of this ‘in the pipeline’ warming will not occur this century. This permits the possibility of avoiding most of that warming, if we reduce the amount of gases in the air on the time scale of a century or two. . . .

Faced with realization that we could hand young people a climate system running out of their control, political leaders took the easy way out. With the Paris Agreement in 2015 they changed the target for maximum global warming from 2°C to 1.5°C. A temperature ‘target’ approach is ineffectual. It has practically no impact on global emissions.

Global energy policies remain inconsistent with professed emission targets. Emission targets will never overrule the desire of nations to raise their standards of living. Effective energy policies, not professed targets, are the crucial requirement for phasing down fossil fuel emissions. . . .

The two essential energy policy requirements are: 1) honest pricing of fossil fuels, i.e., the price must rise to include the cost of fossil fuels to society; 2) government support of breakthrough technologies, including clean energy research, development, demonstration and deployment programs. . . .

The missing technology for China, and now for India, was a clean source of power to replace coal in massive energy requirements for electricity and industrial heat.

Later this century, when scholars look back at what went wrong, the single sentence likely to stand out will be one uttered by President William Jefferson Clinton in his first State of the Union Address, almost three decades ago: “We are eliminating programs that are no longer needed, such as nuclear power research and development.”

How could such a spectacularly bad decision have been reached? Readily available empirical data showed that nuclear power was the safest energy source, with the smallest environmental footprint.

The potential for inexpensive, modular, ultrasafe reactors – built in a factory or shipyard – has not been developed. Support for research, development, demonstration and deployment – lavished on renewable energies for decades – only recently has been initiated in a small way for modern nuclear power. . . .

The most urgent task is to phase down fossil fuel emissions. There is no one simple solution to this. It will take a lot of positive actions, and also pressure on the fossil fuel industry, from multiple directions, pressure on them to become a clean energy industry. . . .

The legal approach is slow and no panacea, but it is an essential part of the solution. [It] must be pursued simultaneously with the political approach. . . .

[Voting Trump out of office is not the answer.] The public has tried that recourse. They voted in Barack (‘Planet in Peril’) Obama and Albert (‘Earth in the Balance’) Gore. The accomplishments by those Administrations in addressing climate change, to use a favorite phrase of my mother, “did not amount to a hill of beans.” Democrats and Republicans are both on the take from special interests, the fossil fuel industry. Both parties work with industry, approving and subsidizing fossil fuel extraction and use.

I wanted to write something today about the impact of tanks on the environment but then thought better of it.