Temperature differences from average around the globe for the planet averaged over the last five years (2014-2018). (NASA)

David W. Titley is a retired Navy rear admiral. He serves as a professor of practice in the department of meteorology at Penn State and is the founding director of its Center for Solutions to Weather and Climate Risk.

There is a common saying on Wall Street that the four most dangerous words are “This time it’s different.” However, for the first time in many years, there are real reasons for optimism in the journey to address the accelerating risks of climate change.

While the most obvious near-term change has been the Democrats’ ascendancy in the U.S. House of Representatives, that is perhaps more a reflection rather than a cause of the underlying transformation.

Harbingers of the change could be seen as early as the summer of 2017, when the Republican-controlled House unexpectedly supported an amendment by Democratic Rep. Jim Langevin (R.I.) to the National Defense Authorization Act, acknowledging the threat climate change poses to the military and directing the Pentagon to identify its bases most vulnerable to climate change. The amendment passed the House and was ultimately signed into law by President Trump even as then-House Science Committee Chairman Lamar Smith (R-Tex.) waged his private proxy war on the National Oceanic and Atmospheric Administration (NOAA) for releasing data and studies contributing to the overwhelming evidence that the earth’s climate is changing rapidly.

The root causes for the changes we are seeing today in Congress likely stem from U.S. citizens’ changing views on how personal, and immediate, the climate threat now appears. These views are changing because of a seemingly ever-increasing number of climate-related extreme weather events, and the greatly increased ability of scientists to definitively link the likelihood and severity of these events to a changing climate.

The media has moved away from a false balance, where a few well-funded doubters were given at least as much airtime as the vast majority of mainstream climate scientists. Additionally, the climate community has honed its message and reports to emphasize that there is vanishingly small uncertainty in the basics of how our climate works, and that the effects of a changing climate are being felt here and now by virtually all Americans.

The past decade was characterized by a disparate series of events over the past 10 years that collectively made for a challenging environment: the Great Recession; what we would today call a cyberattack on climate scientists in 2009 and an attempt to weaponize their internal communications; a random series of years with no major hurricane making landfall on the U.S. coast; and several consecutive years in the early part of the decade that were warm by historic standards, but not breaking records as we had seen in the late 1990s. The forces that wished to see no action taken on climate threats exploited these events and further polarized the American public.

Last December, Yale and George Mason universities conducted another in a decadal series of polling Americans’ attitudes regarding climate change. The December 2018 numbers showed startling changes. The “top line” numbers of Americans who think global warming is happening (71 percent) and who are “extremely” or “very” sure of that belief (51 percent) are back to the levels last seen in 2008, signaling the end of this “lost decade” of climate inaction.

Much more telling in the Yale survey numbers, though, are:

  1. The decrease in the number of Americans who think there is substantial disagreement among scientists about climate warming and its causes (25 percent, a 15 percentage point drop from seven years ago).
  2. A doubling from eight years ago of those who say they have personally experienced the effects of global warming.
  3. A doubling of those who believe people in the United States are being harmed “right now.”

Climate change has moved from an issue that was seen as distant and remote, like a polar bear floating on an ice floe, to one that is here, is real and is happening today. The tweets and statements that the climate was not changing, or that it would soon revert to a cooler state, have lost much of whatever credibility they had, as more and more Americans could see the climate evolve with their own eyes.

Concurrent with the inexorable rise in climate-enhanced extreme weather events is the climate community’s ability to rapidly link the frequency or intensity of the phenomena to the change in climate. This field of climate attribution is a little more than a decade old, but when the science is combined with effective science communication and communicators, the public can easily connect the dots between seemingly abstract climate science and the effects of specific extreme weather events. Additionally, recent reports, such as the Fourth National Climate Assessment, draw the connection between today’s weather and tomorrow’s climate in evermore stark and confident terms.

Recent climate hearings by the House committees on natural resources, energy and science were especially enlightening, mostly for what was not said by the Republican members. Gone was speech after speech of belittling or denigrating the science, or stating “I’m not a scientist.” Conspicuously absent was any remark or support for President Trump’s misguided logic that one cold day in Chicago negates a warming Earth.

Even more remarkably on both the energy and science committees, several Republican members stated that the climate was changing, humans were the reason, and we need to take action. The committees’ minority witnesses fully agreed with the mandate to urgently address climate change and had a constructive dialogue on policy options. Thank you!

Perhaps we are now at the start of the debate about solutions. The Democrats have laid out their concepts for a Green New Deal, with an audacious goal of rapidly decarbonizing the U.S. economy. The Republicans were quick to stand up and take shots at the proposal. Fine. The onus will be on the minority to come up with counterproposals that are realistic and ensure meaningful cuts to greenhouse gases on time scales that matter. We lost a decade since climate change was last considered seriously on the Hill; we cannot afford to waste another 10 years.

After German Field Marshal Erwin Rommel’s army had been defeated in the battle of El Alamein in autumn 1942, British Prime Minister Winston Churchill, in a speech to Parliament, called the victory the “end of the beginning” of the war. We have had false dawns before, but last week’s hearings may, thankfully, have been the end of the pseudo-debate on climate science and the start of a meaningful discussion on what we must do now.