By Ryan Koronowski, ThinkProgress

Following 40 years of sustained fighting on behalf of human health, the environment, and a livable climate, Congressman Henry Waxman (D-CA) announced on Thursday that he would retire from Congress after this year.

“In 1974, I announced my first campaign for Congress,” he said Thursday in a press release. “Today, I am announcing that I have run my last campaign. I will not seek reelection to the Congress and will leave after 40 years in office at the end of this year.” When the news hit the House GOP, their reaction spoke volumes of how strong a legislative adversary he was to them.

A Waxman-less Congress leaves a gaping hole on serious climate policy. Former Rep. Tom Davis (R-VA), the Ranking Member of the House Oversight and Government Reform Committee when Waxman was Chair, described him as a formidable opponent: “he may be short in his stature, but he can be 10 feet tall if you get in his way.”

While the Congressman still has almost a year to add a few more bullet points to his already-full legislative record, here is a short list of his most notable climate and environmental accomplishments:

Climate change stayed a national legislative priority. “To me, this is an issue more important than all the other things we’re spending time on,” he told the National Journal in 2013. “It’s more important than the budget, sequestration, the debt ceiling — 10 years, maybe five years from now, people aren’t going to say, ‘What did we do on those issues?’ They’re going to say, ‘What did Congress do on climate change?'”

There is no EPA regulation of CO2 without Waxman.. The reason that President Obama has the ability to regulate greenhouse gases under the Clean Air Act is because Congressman Waxman helped write it. The existing Clean Air Act was under threat of being weakened from the moment President Reagan was inaugurated for the first time in 1981. At first, Waxman and some of his colleagues merely tried to keep the important bill from being gutted. As the years went by, Reagan and his allies in Congress failed to weaken the Act, and Waxman and his allies ended the decade with a slew of strong amendments. Some of those found their way into a bill that strengthened the Clean Air Act in 1990, signed by George H.W. Bush. The Supreme Court decided in 2007 that the language in the Act meant greenhouse gases could qualify as pollutants under the law. The EPA has been moving to regulate those pollutants since 2009, starting with vehicle emissions and continuing with new and existing power plants today.

The Clean Air Act did not just pave the way for greenhouse gas regulation. It improved air quality in urban and rural areas, cut toxic chemicals, helped preserve the ozone layer, and cut acid rain. By 2020, it will have produced $2 trillion in economic benefits and saved 4.2 million lives. As Waxman put it on Thursday, “It took a decade of effort to pass the landmark Clean Air Act of 1990, but the controls on urban smog, toxic air pollution, acid rain, and ozone-depleting chemicals have saved lives and vastly improved our air quality.”

Water is safer because of amendments he helped pass in the 80s and 90s. After that, the Safe Drinking Water Act protects sources of drinking water, helps remove lead contamination to reduce lead poisoning in children, funds infrastructure projects to maintain reservoirs, and helps consumer to know more about how healthy their water is.

The most famous bill that bears his name is probably the one that never actually became law. Waxman was Chair of the House Energy and Commerce Committee’s Subcommittee on Health and the Environment from 1979 to 1994. In 2009 he dethroned Rep. John Dingell (D-MI), the committee’s top Democrat for 30 years to become Chair of the full committee. He did so with the tacit backing of then-Speaker Nancy Pelosi, and told reporters after the vote “the caucus is responding to the call of the American people for change … I argued that I can deliver that change.” Shortly afterward, while helping to write the Affordable Care Act in his spare time, Waxman dove headfirst into getting the House to tackle comprehensive climate legislation. He succeeded in getting it through the House, but the Senate did not even take it up before the midterm elections in 2010.

Even after defeat, he still kept pushing for a climate bill. The failure of the Senate to pass any climate legislation has not stopped Waxman. Shortly after President Obama’s second term began, Waxman, Senator Sheldon Whitehouse (D-RI), Representative Earl Blumenauer (D-OR) and Senator Brian Schatz (D-HI) unveiled a draft bill that would place a price on carbon. Waxman explained: “In my view a price on carbon makes sense because without it we are essentially subsidizing oil and coal — those fuels are not paying the full cost of the external damages they cause to the environment and public health.” Pricing carbon pollution does have bipartisan and broad ideological support, just not in Congress. Rep. Waxman and then-Rep. Markey penned an op-ed with two Republican Congressmen calling for a price on carbon — the catch is both of them are former Congressmen.

He exposed the Bush Administration’s war on climate science. Then-Chairman Waxman conducted hearings of the Oversight and Reform Committee that examined political interference into government research on climate science. The investigations of his committee found that the White House censored climate scientists, systematically edited government reports to minimize the apparent significance of climate change, and interfered with key legal opinions on greenhouse gases.

Foods now have less pesticides than they used to. Waxman helped negotiate a compromise in the first Congress after the Republicans took over in 1994 that kept more pesticides out of foods.

The auto industry pollutes less and makes more efficient cars. Though the auto industry was afraid of replacing Rep. Dingell (an ardent ally of Detroit) in 2009 with Rep. Waxman (David Cole, chairman of the Center for Automotive Research called Waxman an “irrational environmental zealot”), the auto industry was saved and is now on the front lines of increasing fuel economy and cutting carbon pollution. Business is also good.

Climate action has a caucus. Last year, Waxman helped form the Safe Climate Caucus in the House and the Bicameral Task Force on climate with Senator Sheldon Whitehouse (D-RI) in the Senate. The Caucus has hosted meetings that allow people to describe how climate change is impacting their lives, and how important it is to cut greenhouse gas emissions. When the GOP-controlled House refuses to hold serious hearings, there is now a way for citizens to speak directly to Congress about climate change.

Tea Party obstruction in the House Majority complicates the role of a legislative veteran in the minority. “It’s been frustrating because of the extremism of Tea Party Republicans,” Waxman told the New York Times on Wednesday. “Nothing seems to be happening.”

But it’s mainly, he said Thursday, to give someone younger a try. “The reason for my decision is simple,” he said on Thursday. “After 40 years in Congress, it’s time for someone else to have the chance to make his or her mark, ideally someone who is young enough to make the long-term commitment that’s required for real legislative success.”

“I still feel youthful and energetic, but I recognize if I want to experience a life outside of Congress, I need to start soon. Public office is not the only way to serve, and I want to explore other avenues while I still can.”

It’s unclear who will step into his shoes to forcefully advocate for climate legislation, but the nearly three dozen other House members in the Safe Climate Caucus (such as Reps. Lois Capps, Donna Edwards, Keith Ellison, Tulsi Gabbard, Raul Grijalva, Jared Huffman, Jerry McNerney, Chris Van Hollen, and Peter Welch) could be a place to start.

They’ll need a new website, though, since it’s hosted on Waxman’s personal site.