The Climate Scientist Who Spent 30 Years Warning the World — and What She Said When Nobody Listened

When James Hansen, a NASA scientist, entered a Senate hearing room in Washington on a hot June day in 1988, he said something that ought to have changed everything. He informed the Senate Energy Committee that “the greenhouse effect has been detected and it is changing our climate now.” It was hot in the room. The city was scorching outside. Hansen purposefully picked the moment so that senators could experience the future he was outlining. After presenting the information and responding to inquiries, he returned to the Washington summer. For a brief moment, everyone took notice.

Then it didn’t, for the most part.

James Hansen: Key Facts & Reference

On that day, Hansen, then 47 years old and in charge of the NASA Goddard Institute for Space Studies in New York, had already spent ten years conducting the kind of meticulous, methodical climate research that made the 1988 testimony feasible rather than hypothetical. He was remarkably close to the overall trajectory and accurate in every way that mattered regarding the fundamental direction of travel, even though his models were flawed by later standards (30 years ago, scientists lacked the computing power and accumulated data that inform today’s projections). Since the start of modern temperature records in the 19th century, 1988 proved to be the hottest year. Then, in 1990, 1998, 2010, and three more times between 2014 and 2016, that record was surpassed. In order to accommodate those who found the projections inconvenient, the planet continued to warm.

Journalists visited Hansen at his New York home in 2018 to commemorate the 30th anniversary of his Senate testimony. He retired from NASA at the age of 77 and is currently an adjunct professor at Columbia University. The dialogue that resulted from those interviews was not victorious. He didn’t take praise well when people told him that his predictions had mostly come true because he didn’t think it was a compliment at all. “I don’t want to be right in that sense,” he said. “I wish that the warning be heeded and actions be taken.” The Greeks came close when they created the myth of Cassandra, but there isn’t a clear English term for the kind of frustration he felt after spending thirty years being right about something and seeing the world do nothing about it.

His evaluation of the real results of those thirty years was harsh. “All we’ve done is agree there’s a problem,” he said. He was not impressed by the Paris Agreement, which many had cited as evidence that the world community was finally taking climate change seriously. He referred to it as “wishful thinking” and went on to characterize the larger pattern of climate promises made since the 1990s as a hoax, carried out not by climate scientists but by political leaders who continued to make promises they lacked the structural capacity to fulfill. Hansen contended that the real deception was occurring in the opposite direction—governments taking climate action while permitting emissions to continue rising—while Trump and his allies described climate change as a hoax.

The most remarkable aspect of Hansen’s path may not be the initial testimony or the validation of his science, but rather what transpired after he realized that the science was insufficient on its own. He decided to become an activist at some point in the years after the 1988 warning, a choice that many scientists find difficult to make. He attended demonstrations. He was taken into custody. He joined lawsuits filed by youth against the US government, claiming that their constitutional rights were being violated by the government’s inaction on climate change. This was an important and illuminating decision for a man who had spent decades establishing credibility through meticulous empirical work. It implies that Hansen came to a conclusion regarding the limitations of evidence as a persuasive tool that many of his peers have taken longer to come to.

The language had become even more rigid by 2023. In a statement with two other scientists, Hansen, who is now in his early 80s, warned that the world was approaching temperatures not seen in a million years—prior to human existence—because, in his words, “we are damned fools.” It wasn’t the meticulous wording of a Senate testimony or a journal article. It was the language of someone who had run out of patience. Stronger storms, more intense heatwaves, deepening droughts in areas that cannot afford them, and ice sheets destabilizing at rates that were considered edge-case scenarios in his previous models were some of the emerging climate conditions he described, leaving little room for optimism.

Reading the trajectory of Hansen’s public life gives me the impression that his story is essentially about what happens when someone is correct about something significant and the world’s reaction is to mostly carry on with what it was doing. In an opinion piece published in the Boston Globe around the 30th anniversary, he advised young people to “cast off the old politics and fight for their future on technological, political, and legal fronts” rather than trust the political system that had let him down.

With the directness of someone who has witnessed how these things work, he continued, “It will not be easy.”
The years of record heat continued to come. The trend was consistently confirmed by the data. Recently, the Mauna Loa Observatory, which has been monitoring atmospheric CO2 concentrations since 1958, recorded the biggest increase in CO2 levels in a single year. Hansen is observing all of this from New York, continuing to write and testify to anyone who will listen. Hansen’s career was built on his ability to interpret those numbers precisely. As far as anyone can tell, they are still not content with being correct.