The late President George H.W. Bush is the reason why President Trump has been asked about climate change in the last week more than at any other time in his presidency.

Through legislation he signed in 1990, Bush started the National Climate Assessment, a sweeping study documenting climate change’s impacts on the United States. The Trump administration released the latest iteration on Black Friday and has since downplayed its definitive body of research, making false claims about its accuracy and inadvertently drawing more attention to the clear science that shows Americans will be increasingly at risk as a result of climate change.

Bush’s presidency came during a different time, when bipartisan actions to reduce greenhouse gases and other pollutants seemed possible, observers said. The very existence of the NCA is a reminder that Republicans in Washington once crafted aggressive climate policy.

“We know that the future of the Earth must not be compromised,” Bush told the U.N. Intergovernmental Panel on Climate Change in 1990. “We bear a sacred trust in our tenancy here and a covenant with those most precious to us—our children and theirs.”

Bush died Friday in his Houston home. He was 94.

It was during Bush’s presidency that the federal government stepped up its work on global warming and established an ongoing account of the latest research into how the country would be affected by climate change. Bush was also president during the development of the Montreal Protocol, which drastically cut the chlorofluorocarbons that were destroying the ozone layer.

Through a 1989 presidential initiative, Bush established the U.S. Global Change Research Program, a program encompassing 13 federal agencies that seeks to understand the changing Earth system. The following year, he signed into law the Global Change Research Act of 1990, which mandated that the National Climate Assessment come out every four years.

Top Bush aides recognized that climate change was a serious issue that would require a policy response, according to a series of formerly classified memos released to The Washington Postin 2015 by the National Security Archive.

“If the climate change within the range of current predictions actually occurs, the consequences for every nation and every aspect of human activity will be profound,” acting assistant secretary of State Richard Smith wrote in a 1989 memo.

Thirty years ago, crafting international agreements to address climate change was a Republican concern. Bush’s presidency was a different era for Republican environmental policy, but also a turning point that shifted away from aggressive actions, said William Reilly, who served as EPA administrator under Bush.

“Bush did everything anyone could have asked of on him on climate except commit to stabilization,” he said. “He committed to very substantial research budget to major investments by NASA on upper atmospheric ozone monitoring and on climate monitoring. NOAA was well-funded.”

Bush’s actions on climate change came after what may be his strongest environmental legacy, the signing of the 1990 Clean Air Act amendments. The revisions to the act changed the way the country regulates several key pollutants.

“Building on Congressional proposals advanced during the 1980s, the President proposed legislation designed to curb three major threats to the nation’s environment and to the health of millions of Americans: acid rain, urban air pollution, and toxic air emissions,” EPA states on its website. “The proposal also called for establishing a national permits program to make the law more workable, and an improved enforcement program to help ensure better compliance with the Act.”

Significantly, the amendments targeted acid rain that was destroying forests and lakes, dramatically reducing the pollution that caused the problem to such an extent that it is no longer a major issue in the United States.

But the political capital Bush spent on the Clean Air Act diminished his work on climate policy, Reilly said. At the Group of Seven meeting in Paris in 1989, environmental groups trashed Bush for not committing to a stabilization of greenhouse gases, Reilly recalled.

That convinced Bush that pushing too far on environmental policy would hurt him politically with his base while failing to win any converts on the other side.

“That was kind of the beginning of Bush’s disillusion about his likely winning popularity by things he did in the environment,” Reilly said. “From the point of view of the environmentalists, he was Reagan’s vice president. And he did the Clean Air Act, he got really nothing for it ... Bush decided finally, and the people around him had decided long before, that the environment would not work for him politically.”

Since Bush left office, his Republican predecessors, George W. Bush and Trump, have been increasingly hostile to climate science and have resisted meaningful policy to reduce greenhouse gas emissions. Much of their criticism has centered on the economic costs of environmental policy, a stance that environmental groups have widely denounced.

The latest National Climate Assessment shows that climate change will kill more Americans, displace thousands and cost tens of billions of dollars annually. Democrats have touted the findings as evidence that the government needs to craft significant climate policy and have promised to use its revelations in court cases challenging the administration. Some Republicans have acknowledged that the report requires action from Washington, as well, but most have questioned its findings without presenting any evidence to the contrary.

Trump has said he doesn’t “believe” the report. The United States was the only country at the Group of 20 meeting this weekend to refuse to sign a statement reiterating support for the Paris climate accord (see related story).

By contrast, the late Bush was able to craft bipartisan environmental policy that has had a lasting effect, said Jason Bordoff, a former Obama administration energy and climate policy aide and the founder of the Center on Global Energy Policy at Columbia University’s School of International and Public Affairs.

“From promoting cap and trade to curb acid rain to an international agreement protecting the ozone layer to climate change research, President George H.W. Bush was part of a Republican tradition of support for environmental protection, science and bipartisan cooperation that unfortunately is too rare these days,” he said.

Environmental groups have been some of the harshest critics of George W. Bush and Trump. By contrast, they issued a number of statements of praise for the environmental legacy left by George H.W. Bush.

“By cutting pollution from cars, trucks, power plants and other sources, the measures have sharply reduced toxic chemicals in the air we breathe, dangerous ozone and the acid rain that was destroying American forests,” said Rhea Suh, president of the Natural Resources Defense Council, in a statement. “The measures decreased asthma attacks, bronchitis, heart disease and other ills, preventing some 200,000 premature deaths and 20 million lost days at work or school every year to deliver up to $90 in public health benefits for every dollar invested in compliance.”

Bush was capable of seeing that protecting the economy and the environment did not have to be in contrast, said Fred Krupp, president of the Environmental Defense Fund, who worked with Bush to help pass the bipartisan Clean Air Act amendments as well as ratify the 1992 U.N. Framework Convention on Climate Change.

Krupp said Bush deserves credit for curbing acid rain pollution that was devastating Northeastern forests in the 1980s. He noted that sulfur dioxide pollution, which caused the acid rain, has been cut 88 percent since 1990.

“He knew that our country matters far more than political party or personal ambition, and that the national interest demands that we protect America’s precious natural heritage,” Krupp said in a statement. “And he knew that there is no inherent conflict between environmental progress and economic progress, because the well-being of the nation requires both.”

Reporter Robin Bravender contributed.

Reprinted from Climatewire with permission from E&E News. E&E provides daily coverage of essential energy and environmental news at www.eenews.net.