More than a year after Donald Trump lost the presidency, election officials across the country are facing a growing barrage of claims that the vote was not secure and demands to investigate or decertify the outcome, efforts that are eating up hundreds of hours of government time and spreading distrust in elections.

The ongoing attack on the vote is being driven in part by well-funded Trump associates, who have gained audiences with top state officials and are pushing to inspect protected machines and urging them to conduct audits or sign on to a lawsuit seeking to overturn the 2020 results. And the campaign is being bolstered by grass-roots energy, as local residents who have absorbed baseless allegations of ballot fraud are now forcing election administrators to address the false claims.

The fallout has spread from the six states where Trump sought to overturn the outcome in 2020 to deep-red places such as Idaho, where officials recently hand-recounted ballots in three counties to refute claims of vote-flipping, and Oklahoma, where state officials commissioned an investigation to counter allegations that voting machines were hacked.

State and local officials said no one has presented actual evidence that rampant fraud tainted the 2020 election, and numerous ballot reviews and legal proceedings have affirmed that the vote was secure. Yet they and their staffs have been forced into a high-stakes game of whack-a-mole, debunking a steady stream of false allegations only to see similar claims emerge again from other groups or in another states.

The onslaught is exhausting and troubling, officials said, as they launch preparations for the 2022 midterm elections - and is further eroding faith in the nation's voting systems.

"If we want to continue to provide safe, secure and accessible elections, constantly running down absurd conspiracy theories is not sustainable," said Patrick Gannon, a spokesman for the North Carolina State Board of Elections. "For many election workers, this has become a full-time job."

Among those leading the efforts against the 2020 presidential election are MyPillow founder Mike Lindell - who said in an interview this week that he has spent $25 million promoting claims of election fraud - and one of his associates, Douglas Frank, a longtime math and science teacher in Ohio who claims to have discovered secret algorithms used to rig the 2020 election.

Throughout the year, the two men have been pressing their case with state and local election officials around the country and gaining meetings with many of them, according to people familiar with their activities.

In Ohio, Frank met for more than two hours in May with the senior staff of Ohio Secretary of State Frank LaRose, a Republican, presenting unsubstantiated claims that voting machines are connected to the internet and have been hacked, according to a recording of the meeting obtained by The Washington Post. Frank warned that he planned to pursue multiple legal actions around the country and said there could be consequences if LaRose's office did not cooperate.

"I'm warning you that I've been going around the country. We're starting lawsuits everywhere," Frank said, according to the recording. "And I want you guys to be allies, not opponents. I want to be on your team, and I'm warning you."

After the meeting, LaRose posted a video on Facebook reiterating that under state law, no voting machines are connected to any network.

The doubts that Lindell, Frank and other Trump allies have whipped up about the vote have taken root across the country.

In North Carolina this fall, local activists and at least two Republican lawmakers sent the State Board of Elections allegations, including an outlandish claim that all 100 county election systems were hacked in 2020 and thousands of votes for Trump switched to Joe Biden. Election staffers and the state's cybersecurity team compiled dozens of pages of responses disproving the charges, one at a time.

And in Marion County, Fla., this fall, some local residents conducted their own canvass of 2020 voters and presented their findings to election officials, claiming that many who cast ballots were "ghost" voters who didn't actually live at the addresses listed on their registrations.

As in other instances, their claims were debunked. Wesley Wilcox, the Marion County elections supervisor and a Republican, said the activists made the "absurd" claim that the number of voters who were registered but did not cast ballots in 2020 was evidence of fraud. He noted that the objectors did not provide the name of a single voter who was improperly registered at the time of last year's election.

"They're trying to prove voter fraud off of nonexistent issues," Wilcox said.

Even as election officials rebut the growing conspiracy theories, the demands from some of those pushing false claims are escalating - and their rhetoric is becoming more extreme.

On social media, Frank recently began calling for prison or "firing squads" for those who do not agree to hear him out. On Saturday, he wrote that Michigan Secretary of State Jocelyn Benson, a Democrat who has refused to entertain his claims, should face a jury "capable of dispensing capital punishment."

In an interview this week, Benson said she views the latest escalation as an assault on democracy. She said she intends to spend next year fighting back, and urging Americans to do the same.

Benson called the pressure on election officials "a political strategy to break down our democracy and put people in charge of our states who are unaccountable and will act in a way that doesn't reflect the will of the people."

Asked Tuesday about his comments, Frank said that after he and others who share his view about 2020 "win the war," election officials such as Benson should face trial - adding that federal law calls for traitors to be subject to capital punishment.

"After the Nuremberg trials, there were hangings and firing squads," Frank wrote in an email, referring to the military tribunals that tried Nazi leaders after World War II. In an interview, he added that he believes it is critical for officials to investigate elections to restore faith in their outcome: "I firmly believe they are not fair and free. I believe they are being manipulated."

Lindell previously told The Post that he has hired Frank for some projects but that he is not aware of all of his activities. In an interview this week, Lindell said he is working hard to protect democracy and prays for people who believe that he's undermining it.

"What happened in 2020 was completely the biggest crime in the history of the United States, probably the world," he told The Post. "I'm not backing down, and I hope you wouldn't, and anyone wouldn't in this country, if they knew what I knew."

Asked about the fraudulent claims and incendiary rhetoric used by his allies, Trump spokeswoman Liz Harrington said in a statement that the former president "supports any patriotic American who dedicates their time and effort to exposing the rigged 2020 Presidential Election."

- - -

Trump is leading the ongoing assault on the integrity of the 2020 election, regularly firing off statements in which he falsely asserts that the vote was rigged and using the issue as a litmus test for which candidates he endorses.

In a statement Tuesday, he said that the real "insurrection" happened not on Jan. 6, when a mob of his supporters stormed the U.S. Capitol, but on Nov. 3, the day Americans elected Biden.

When Frank met with LaRose's senior staffers in May, he twice told them that he would be calling the former president immediately afterward to provide an update, according to the recording.

Frank told The Post this week that when he told Ohio officials he would be calling the former president, he didn't mean it literally. He said he meant to show that he had connections to powerful people who could be helpful.

"I didn't mean it as a threat. I meant it as an opportunity," he said.

In June, Frank spoke at a Trump rally in Ohio, despite the objections of some Trump aides, who opposed his making a dry PowerPoint presentation about fraud theories to the crowd, according to people familiar with the event. Backstage, Frank conferred with the former president and a number of his advisers, according to a person who was present. Frank has separately spoken to Harrington, an adviser said.

Lindell interviewed Trump at his Florida club this fall for a show streamed on Lindell's website, and the former president has praised the MyPillow executive for "fighting" for him, a Trump adviser said.

At the Trump rally in Ohio this summer, Lindell could be heard telling throngs of Trump fans that he would be showing more evidence "soon" as they mobbed him for photos.

Frank has been open in his quest to recruit state and local officials to his cause. He has told The Post in recent months that he has visited "over 30 states" and has met with about 100 election administrators. In April, he spoke to Tina Peters, the clerk in Mesa County, Colo., "and showed her how her election was hacked," Frank previously told The Post.

The following month, Peters allegedly brought an outsider into her election offices to copy the hard drives of voting machines, an episode now under criminal investigation. Peters has said that she gave access to the outsider to help preserve election records and that doing so was within the scope of her responsibilities.

Lindell told The Post that he has spoken to "20 to 30" Republican attorneys general in a bid to persuade them to sign on to a lawsuit asking the Supreme Court to nullify the 2020 results in key states Biden won. He announced in early November his plans to file the suit two days before Thanksgiving, but the date came and went and no attorney general had agreed to do so. Lindell posted the complaint online without named plaintiffs and, without offering proof, accused Republican National Committee Chairwoman Ronna McDaniel of sabotaging his effort.

Lindell said Tuesday that he remains in regular contact with about a dozen attorneys general, whom he declined to name, and that he still expects them to file a revised version of the lawsuit. He said that his claims about McDaniel were based on something he heard, and not on evidence. But, he added, "the RNC collects a lot of money, and never did anything for the election crimes."

In a statement, RNC spokeswoman Danielle Alvarez called his criticism "reckless and completely false," saying the national party financed 50 election-related lawsuits in the last election cycle and is pursuing more than 30 suits now.

"We will continue to act and get results while others continue to do nothing more than talk," she said.

Numerous election security experts have dismissed the fraud allegations made by Lindell and Frank, but the claims have found traction among some Republican legislators.

In North Carolina this fall, a Republican state lawmaker sent officials an ominous-looking map of the state showing red lines identified as "remote connections" emanating like laser beams from all of the state's 100 counties.

State officials said there is no merit to the document, which attributes the information to retired Army colonel Phil Waldron, another Trump ally who has challenged the results of the election.

"The State Board continues to have no credible evidence of the 2020 general election results being manipulated in any way," said Gannon, whose office has received dozens of inquiries demanding forensic audits and explanations about the vote.

Earlier this month, Waldron was revealed to have briefed some members of Congress ahead of the congressional certification of the vote on Jan. 6 with a PowerPoint presentation that proposed options for replacing or rejecting Democratic electors in "states where fraud occurred."

Waldron did not respond to a request for comment.

The "remote connections" chart, along with other documents, was sent to North Carolina officials by state Rep. George Cleveland, a Republican. He asked for a "complete" explanation of what had happened in the election, according to emails obtained by The Post through a public-records request.

Gannon responded with detailed explanations, not only from his office, but also from the North Carolina National Guard, which runs the state's Cyber Security Response Force and is responsible for monitoring election security. In response to one claim alleging manipulation of vote counts, the State Board of Elections wrote, "The allegation is so vague as to be incomprehensible."

In an interview, Cleveland said he was satisfied that North Carolina's system was not hacked. But he said he remains convinced that the 2020 election was rigged in other places - a common position among those who have been convinced that there was no widespread fraud in their own states.

"When I first saw Frank's presentation on the polynomial thing, I was impressed," Cleveland said, referring to the claim that an algorithm Frank calls a "6th-degree polynomial" was used to rig the 2020 results. "He did a very good job. But after I've looked into some other things and talked to other people, until he will give his data and his methodology to others to prove what he's saying, I'm going to be very skeptical."

- - -

Lindell held a "cyber symposium" in August where he showcased claims of fraud and spent the ensuing weeks meeting with officials who asked him to present them with his evidence, he told The Post. In September, he told The Post that he had met with officials in states including Florida, Missouri, Alabama, North Dakota and South Dakota.

"I've been going state to state and showing them evidence directly, and they all want to do audits," Lindell said at the time.

Frank said he is often asked for help by local activists who have seen his presentations online or his posts on the social media site Telegram.

"Someone will call from a state and say, 'Dr. Frank, our elections are ripped off. Will you come help us?' " he told The Post last month. "They seek me out; I'm not seeking them out."

After he gives a talk in a community, Frank said, "hundreds of people are now motivated, or maybe a thousand people are motivated by my talk, and they start canvassing, calling legislators and calling county officials. They call me back and say, 'Hey, we'd like you to come meet with this legislator and this county clerk.' "

He said he has met personally with numerous state officials, including Missouri Secretary of State Jay Ashcroft, a Republican. On Dec. 1, Frank wrote on Telegram that he had "negotiated a deal" in which Ashcroft "agreed to take up the cause if we brought him 100 phantom voters."

Ashcroft declined to comment, as did several Republican officials whom Lindell or Frank said they contacted.

Other state officials have handled the outreach gingerly by agreeing to listen to the election deniers, but then stating publicly that there is no evidence of fraud.

Alabama Secretary of State John Merrill, a Republican, said in an interview that he met with Lindell and Frank twice this fall - and traveled to Trump's private club in Florida this month to meet with the former president. Merrill described the meetings as cordial and said he is always willing to meet with anyone, but he also said that the allegations of a rigged election did not have merit.

Lindell claimed to have IP addresses and passwords proving that Alabama elections systems had been hacked, but he did not present any in the meeting, Merrill said. The dozens of voters registered to a single address that Lindell said proved that the voter rolls were fraudulent were actually residents of Big Oak Ranch, a well-known community where children from troubled homes live with foster families.

Merrill said he personally knows a couple of the voters living at Big Oak Ranch whose names were presented to him as evidence of fraud.

"A simple Google check would have told you what these places are," Merrill recalled telling the pair. "Instead you reached a supposition that voter fraud occurred."

Frank acknowledged that the meeting did not go well. "We have since changed our approach as a result," he said.

In an interview Tuesday, Lindell continued to insist that more than 100,000 votes were flipped from Trump to Biden in Alabama, and he alleged that since his meeting with Merrill, his investigators uncovered more vulnerabilities in Alabama's electronic poll books.

"We're going to be circling back to Alabama, obviously, long before the 2022 election and show him that the machines are defective," Lindell said.

After the meeting, Merrill said he sent letters to every registrar, court clerk, probate judge and sheriff in the state, warning them not to provide information to Lindell or Frank that is not readily available to the public because state law forbids it. Merrill said that he is not aware of anyone doing so and that if it happens, "I will personally contact the district attorney in that circuit and seek an indictment."

In Ohio, Frank got an audience with LaRose's staff after connecting with Joe Blystone, who is challenging Gov. Mike DeWine for the GOP nomination in part on a platform claiming that fraud tainted the state's elections last year. Blystone in turn made contact with someone he knew in LaRose's office and requested a meeting, according to both Frank and Blystone, the latter confirming in an interview that he set up and attended the meeting.

In the meeting, Frank claimed he had abundant evidence, but when staff members asked to see it, he said it was coming soon, according to the recording. At one point, Frank said voters in Ohio were sent absentee ballots without requesting them - a recipe for fraud, he argued.

State officials pushed back, explaining that voters actually received forms to request absentee ballots, not the ballots themselves. Frank quickly backtracked, conceding that he did not yet have the evidence about the ballots, according to the recording.

At other moments, Frank suggested that there could be political consequences for LaRose if he did not cooperate, according to the recording. He said he would like to send a forensic team to find evidence of fraud by inspecting voting systems. And he claimed that there are people - "plants," he called them - across the country collecting proof that voting machines are connected to the internet and therefore susceptible to being hacked.

"We can arrange for that" in Ohio, he said, according to the recording.

Frank told The Post that all of his comments were offered in the spirit of helping Ohio officials expose fraud and that he was disappointed they did not take him up on that offer. He also claimed to know of evidence of election fraud that has not been presented publicly because of national security sensitivities.

LaRose spokesman Rob Nichols said the office denied Frank's requests, but he added that the secretary's office is open to meeting with any group claiming to have evidence of voting irregularities and did not find Frank's inquiries burdensome.

In an interview in November, LaRose offered a blunt assessment of Frank's theories.

Almost nobody "knows what a sixth-order polynomial even is, and it's got nothing to do with how elections are run," LaRose said. "But it sounds impressive, and if you have a preconceived sort of notion about what you want to believe and somebody with a title tells you a bunch of things, this is what conspiracy theories are based on."

Even in states that Trump won overwhelmingly, officials have been compelled to address fraud claims.

After Lindell's symposium in August, Oklahoma lawmakers under pressure from their constituents asked State Election Board Secretary Paul Ziriax about Lindell's claim that tens of thousands of votes were flipped in each of Oklahoma's 77 counties.

Ziriax requested an independent investigation that found no merit to those claims, he told members of the state legislature in a letter in October.

In Idaho, Chief Deputy Secretary of State Chad Houck said that he has not spoken with Lindell or Frank but that his office has fielded phone calls and emails from people asking what state officials planned to do about assertions on Lindell's website that the results were electronically manipulated in all 44 counties in Idaho.

Houck said he knew that the claim was bogus but that he didn't want to just say so - he wanted to show it. So in late September, state officials conducted a full hand-recount of ballots in two small counties, which showed that there was no vote-flipping, as Lindell alleged. They filmed the process, posted footage online and issued a news release.

In early October, they counted a sample of ballots in a larger county, and Houck issued a second news release declaring Lindell's claims "without merit."

"It takes hard work to build confidence in a state's elections system, and careless accusations like this can cause tremendous harm. Doing nothing and saying nothing would have been like conceding its truth," Houck said in a statement at the time.

That posture could cost Houck, who is running for secretary of state in the deeply Republican state. But he said it was important to speak out.

"You put the facts out and you let the chips fall where they may," he told The Post.

Paul Thomas Anderson writes films about the San Fernando Valley the way some besotted admirers compose love letters. Yet while growing up there, he didn't fully realize just what his native terrain would mean to him.

"My awareness of where I was living, it was all half-natural," says the filmmaker who, as a Valley kid, would cross paths with former celebrities, and stand where storied backlots once stood.

He recalls visiting friends in an Encino Village development on the land where, he learned only later in life, the razed RKO Pictures location ranch had been a creative hotbed. This was where such classics as "Cimarron," "Stagecoach" and "It's A Wonderful Life" were shot, before Bedford Falls was bordered by strip malls.

"Whatever our collective subconscious feels, these films that we love were germinated here," Anderson says of the site. And for his latest film, "Licorice Pizza," Anderson returned to the Valley, the area of L.A. County just over the hill from Hollywood.

Shooting close to home during the pandemic, with a cast and crew of Anderson's friends, was physically practical. Yet by revisiting the area where he set such works as "Boogie Nights," "Magnolia" and "Punch-Drunk Love," the writer-director says he also found inspiration: These former farmlands cited in "Chinatown" still offer Anderson, 51, a terroir filled with recollections, lore and phantom narrative threads. Where some might view Valley communities like his native Studio City as "the most suburban of suburban neighborhoods," Anderson sees the underpinnings for high drama.

Opening wide on Christmas Day, the film is a sense-memory romp set on the sidewalks that shaped him. Anderson is ever attuned to the area's cultural echoes and ghosts: "I'm one of those people who loves to drive down the street and look at all the old buildings or see what's left."

Those ghosts include Licorice Pizza itself. The film's title is an allusion to the era's LP-stocked store chain that stretched across Southern California when vinyl was king.

He also can still picture the woman who lived across from his boyhood Studio City home - a sweet and beautiful grandmotherly figure of impeccable taste with her little sandwiches and traditional English tea set. "I didn't even realize at the time," he says, "that I was with Hollywood royalty."

Mary Brian had come to California as a teenager during the Jazz Age, soon to be discovered by Paramount Studios. The budding actress earned her first credit in the 1924 silent film "Peter Pan" and went on to act opposite Gary Cooper and Cary Grant.

"I wish I'd been older, I wish I'd known more, I wish I'd paid more attention," Anderson says of his neighbor, who became engaged to Grant before marrying frequent Hitchcock editor George Tomasini. She died in 2002 at age 96.

Anderson weighs the memory. "I wish I could go back."

He became attentive to moments that might spark his screenwriting mind.

About two decades ago, Anderson passed a Tarzana middle school on picture day, for instance, when he witnessed a student's interaction that became a premise for "Licorice Pizza." The film opens with 15-year-old Gary Valentine (portrayed by Cooper Hoffman, son of the late actor and regular Anderson collaborator Philip Seymour Hoffman) trying to charm Alana Kane (Alana Haim), a photographer's assistant about a decade older.

Addressing their connection despite their ages, Anderson calls Gary and Alana's friendship "undeniably platonic," though "certainly on his end, it's flirtatious." The film's central link, he says, is between an adolescent trying to act like an adult and an adult wary of letting go of her lingering emotional adolescence. The film has sparked ongoing social-media debate over the adult character's relationship with a child, as well as for its gags involving a White restaurateur and his Japanese wives that some critics have called insensitive and racist.

"The interesting thing about Gary," Anderson says, "is that he comes across as quite smooth in the beginning, but very rapidly, you see that he's kind of out of steam," revealing his inexperience. Gary is growing out of his career as a child actor. Looking for an entrepreneurial hustle, he sells water beds - nodding lightly to Seymour Hoffman's role as a blackmailing "mattress man" in "Punch-Drunk Love" - before opening a vividly lit pinball palace.

The story of this businessmanchild was inspired by Anderson's friend Gary Goetzman, the former kid actor (1968′s "Yours, Mine and Ours") who co-founded the production company Playtone with Tom Hanks, and worked often with one of Anderson's filmmaking heroes, the late Jonathan Demme.

Goetzman's teen experience in the Valley preceded Anderson's, but the director sees it "as this catch-all for everything that I knew - none of this stuff happened to me directly, but I knew it and I felt it."

Young Goetzman once sold a water bed to famed hairdresser-turned-Hollywood producer Jon Peters, an anecdote Anderson spins into careening scenes of fiction featuring Bradley Cooper, who plays Peters as a libidinal, wild-eyed dervish.

The veteran actors - including Sean Penn in a role partly inspired by William Holden's latter midlife-crisis characters - are there to serve the core story of youth. The director's view: "Every adult relationship has this mileage on it that these kids don't have." Gary can pinball from one adventure to the next, mostly slipping the friction of grown-up consequence.

Anderson turned to his personal Valley circle to cast his female lead, too. When he was an elementary student at the Buckley School in the '70s, Anderson was captivated by his art teacher, Donna Rose-Haim. "Miss Rose" would bring an acoustic guitar to class, and even played a Bonnie Raitt cover on TV's "The Gong Show."

Decades later, Anderson would direct music videos for her daughters Este, Danielle and Alana of the popular band Haim. The real-life family plays a fictional family in "Licorice Pizza."

Alana, who's said to be the spitting image of Mom, delivers an award-worthy performance opposite Hoffman in her acting debut. Haim, 30, says some scenes from the film remind her of her own upbringing.

"The Valley has been such an important part of my life - even meeting Paul," Haim says of the director. "One of the first things we connected on was growing up in the Valley." Part of that experience, she says, involved "this weird narrative that everyone thinks you're uncool." Yet being raised there, "You have this certain sense of pride because everyone thought you were uncool."

The Valley could be something of a punchline decades ago, when Johnny Carson was joking about beautiful downtown Burbank, or when a character in 1967′s "The Graduate" was declaring Tarzana to be quite the trek from Beverly Hills.

Anderson says that given how much the area has grown and evolved, though, "I would be shocked if the San Fernando Valley comes in for any more trash talk."

The director, like some other Valley kids, grew up with connections to Hollywood. His father, Ernie Anderson, was an announcer and voice-over performer for such programs as "The Carol Burnett Show" and "The Love Boat." Before that, Dad was a popular TV horror host in Cleveland who went by the name Ghoulardi (now the title of the director's film company), as well as comedy partner of future "Carol Burnett" star Tim Conway.

In the film, the director re-creates long-shuttered places, like the Valley location of the Tail o' the Cock restaurant, where Hollywood stars and Burbank animators would dine alongside families unattached to the industry. He also is inspired by rumors from that era: Did Evel Knievel really attempt a motorcycle stunt outside the old Ram's Horn Restaurant in Encino? For purposes of a shaggy Anderson tale, the truth is beside the point.

The director even shoots in a home off Ventura Boulevard that has ties to yet another "Carol Burnett" star, Lyle Waggoner, according to Thrillist. The director cherishes what has survived the passage of time: "I'm the person who's crying in my beer complaining about progress as you see something bulldozed away. It makes me incredibly melancholy."

Anderson says he can feel powerless in the face of such change. But he can resurrect the memories through his lens. Because on screen, this is not just the Valley. It is his Valley.

CIUDAD OBREGÓN, Mexico - In the foothills of the Sierra Madre mountains, the carcasses of starving cattle rotted in a bone-dry reservoir. Useless fishing nets hung on dusty fences. Rowboats were stranded in the sand.

Down on the valley floor, Rafael Parra bent to the work of feeding the world - and unintentionally warming it.

A layer of chalk-white fertilizer had been scattered on the barren ground. Tractors had cut long furrows in the dry and crumbling soil. The wheat seeds would not be planted for days, but it was time to release the laughing gas.

Parra plunged one end of an old, plastic tube into an irrigation canal, generating the suction that sent water gurgling into the drought-parched earth. It was a low-tech, gravity-fed form of irrigation used for generations here in the Yaqui Valley, a storied breadbasket of Mexico.

"That's all there is to it," he said.

Parra, like many farmworkers here, was not fully aware of the invisible consequences of his work. But scientists who have studied this valley for decades know that in these precise moments and conditions - when water mixes with nitrogen fertilizer, and when no crop is in the ground to absorb it - huge surges of nitrous oxide gas are released into the atmosphere.

The world's climate conferences and pledges have done nothing to change a basic and dangerous fact: Concentrations of major greenhouse gases in the atmosphere continue to rise. And what happens each fall in this valley underscores how difficult it is to even track these emissions accurately, let alone stop them.

Emerging scientific evidence suggests that Mexico's emissions of nitrous oxide are significantly underestimated - emissions may be double or even quadruple what the country reports. It's a problem that the Mexican government acknowledged to The Washington Post for this story.

As a contributor to climate change, nitrous oxide remains a mysterious villain, crudely measured and less-studied than carbon dioxide and other greenhouse gases. But it has caused 6.5% of the world's current warming, and its concentration in the atmosphere is growing at an accelerating rate, surpassing even some of the worst projections. The gas is 265 times more powerful than carbon dioxide in heating the atmosphere over a period of 100 years. It depletes the planet's ozone layer. And it lingers in the air for more than a century.

Last year, atmospheric concentrations of nitrous oxide showed a record-high increase, according to the National Oceanic and Atmospheric Administration.

The families who grow wheat in the Yaqui Valley run some of the most sophisticated, large-scale commercial operations in the country - the type of highly productive, heavily irrigated agricultural system essential for feeding billions of people. The bulk of their crop is durum wheat, which is exported by cargo ship to countries in Africa and Latin America for foods such as pastas and couscous. The rest is kept local for breads and tortillas.

The problems with the over-fertilization found here, in the world's 10th-largest greenhouse gas emitter, are also common for the developing world. Wheat farmers in the Yaqui Valley apply about 300 kilograms of nitrogen onto every hectare of land they cultivate - primarily by scattering urea pebbles onto the soil before planting and later pumping anhydrous ammonia gas into the irrigation water once the wheat starts growing. That rate of nitrogen use is 50% higher than what is allowed by law in parts of Germany. Britain prohibits fertilizing before planting in vulnerable areas - a common practice in the valley.

"Indeed, these rules do not exist in Mexico," Juan Gabriel León Zaragoza, a spokesman for Mexico's Agriculture Ministry, said in a statement to The Post. "In part because these types of regulations are difficult to enforce, especially considering the size of our country compared to European countries."

Without regulation, the fight against nitrous oxide pollution is left to people such as Iván Ortiz-Monasterio, a 63-year-old agronomist from Cuernavaca who has spent his career trying to convince farmers to use nitrogen more efficiently. Research by Ortiz-Monasterio and his colleagues has shown how farmers in the Yaqui Valley often use roughly double the amount of fertilizer necessary and that much of the excess nitrogen was being lost to the environment.

Over decades working in the valley, the soft-spoken scientist developed an intimate knowledge of the financial and cultural pressures that encourage wheat farmers to apply too much fertilizer - even when they could save money and pollute less.

"For the farmer, the cost of fertilizing too much is less than the cost of fertilizing too little," Ortiz-Monasterio said. "That's because they are not taking into account the environmental cost."

Recent research by Ortiz-Monasterio and others also suggests the problem is far worse than is generally known. They have found that as farmers add more and more fertilizer, the resulting emissions begin to grow by disproportionate amounts, increasing on an exponential curve. The research has become a key clue that could help explain the huge gaps that exist between the amount of nitrous oxide that countries - including Mexico - claim to emit, and what atmospheric studies find.

This was not a problem that Norman Borlaug - an American expat who became the Yaqui Valley's most famous farmer - contemplated when he began, in the years after World War II, to experiment with varieties of wheat in the Sonoran fields. The discoveries that the Iowa-born plant pathologist made would help end famines in South Asia, win him a Nobel Prize and launch the "green revolution," which spread high-yielding varieties of wheat and rice throughout the developing world.

But Borlaug also left a legacy of heavy reliance on synthetic fertilizers, which have become increasingly problematic as the world warms. There is growing evidence that the over-application of fertilizers - particularly in developing nations with growing agricultural industries such as Brazil, India, China and Mexico - is a central driver accelerating the nitrous oxide emissions that contribute to climate change.

"It's just the ultimate story of unintended consequences," said Marci Baranski, an expert on greenhouse gas emissions and author of a forthcoming book about Borlaug and the green revolution.

At the renowned agricultural research station where Borlaug once worked, Ortiz-Monasterio and other scientists have spent decades documenting the environmental damage that excess nitrogen can cause for the air and water. The station is the International Maize and Wheat Improvement Center, known by its Spanish initials, CIMMYT. Starting in the 1990s, they began taking emissions measurements - using simple PVC chambers at ground level, extracting the gas with syringes. The results shocked them.

"They were the highest that anybody had seen in the world at that point," said Stanford University ecologist Pamela Matson, who has conducted extensive research in the Yaqui Valley. "It was mind-blowing how large those emissions were."

- - -

Ciudad Obregón was built for farming. The streets are grid-straight and extra-wide to accommodate the convoys of diesel-powered cargo trucks passing through to fields and ports. Cylindrical silos and sprawling wheat depots line the valley that spans a half-million acres amid a network of irrigation canals connected to three reservoirs.

The canals are what allowed the southern tip of the Sonoran Desert to become an agricultural powerhouse. In the early 1900s, a pair of Los Angeles-based entrepreneurial brothers, W.E. Richardson and Davis Richardson, developed them, attracting investors for their vision of a railroad-connected, farming boomtown by advertising "the most fertile irrigated land on earth" and selling parcels for $25 an acre. The Indigenous Yaqui people who lived there first would fight bloody battles with the Mexican army as they lost control of rights to the Yaqui River in a water conflict that lingers to this day.

Borlaug landed in the valley in the 1940s as an agricultural adviser for the Rockefeller Foundation while the farmers around him were beset by a fungus known as stem rust. His success during his career established the Yaqui Valley as an international hub for agricultural science.

"This became a mecca for investigators who wanted to improve wheat," said Pedro Figueroa Lopez, an agronomist who recently retired after a career in wheat improvement with the Mexican government. "And people have come from many countries. And they still come here."

Ortiz-Monasterio now works out of a building on one of the city's main thoroughfares: Boulevard Dr. Norman E. Borlaug. His office at CIMMYT is fronted by a bronze statue of Borlaug standing amid sprigs of wheat.

In some ways, Ortiz-Monasterio's work mirrors that of his predecessor, who died in 2009. Like Borlaug, Ortiz-Monasterio is part scientist, part unofficial diplomat, traveling widely and teaching ways to grow wheat. But their differing messages point to an underlying tension.

Borlaug's mission was yield. He wanted wheat grains to be more bountiful, hardier and more adaptable to places around the world. His great innovation was to go shorter, developing what was known as semi-dwarf wheat whose stems would not bend under the weight of larger grains. In the 1950s and '60s, those Mexican seeds were introduced in India, Pakistan, China and elsewhere, allowing rapid expansions of food production that staved off hunger for millions of people.

In the countries where Borlaug worked, nitrogen rates were low and heavy fertilization was central to his message. When the Indian government in the 1960s wanted to spread its fertilizer supplies evenly throughout the country, Borlaug opposed that, arguing that the focus should be on "tremendous yield increases" in certain commercially farmed areas that could be "heavily fertilized and properly watered."

Since then, global nitrogen fertilizer use has risen sharply, growing from about 10 million metric tons in 1960 to 111.6 million metric tons projected in 2022, according to the Food and Agriculture Organization of the United Nations. Farmers in the Yaqui Valley have followed suit. Surveys by CIMMYT over the decades show that average nitrogen use has risen roughly sixfold since 1960.

For decades Ortiz-Monasterio has fought an uphill battle to bend that curve downward. Trained at the University of Illinois, he joined CIMMYT in 1989 and soon began collaborating with Stanford scientists, including Matson, who would win a MacArthur Foundation fellowship, known as a "genius" grant, in 1995.

Then as now, Yaqui Valley farmers would scatter heavy doses of fertilizer on bare ground, irrigate and wait for days or weeks before planting. In these wet conditions, soil microbes break down a compound called nitrate in a process that unleashes nitrous oxide into the air.

"The big pulses of nitrogen follow that perfect condition, where there's no plants taking nitrogen up, there's lots of it available in the soil, and microorganisms are using it for their own energy sources," Matson said.

One of her graduate students at the time, Michael Beman, began investigating how the excess nitrogen seeped through drainage canals into Bahía del Tóbari and other outlets to the Sea of Cortez in northwestern Mexico. Using satellite imagery between 1998 and 2002, Beman and colleagues discovered algae blooms up to 220 square miles large that followed just days after the periodic irrigations in the valley.

This part of the ocean has naturally low levels of nitrogen, Beman said, so bursts from the farmlands are having an outsize impact.

Satellites can measure phytoplankton by using algorithms to calculate the concentration of chlorophyll based on the colors in the water. Gene Feldman, a NASA oceanographer and an expert on ocean color remote sensing, reviewed imagery from satellites off the coast of the Yaqui Valley at The Post's request. He noted that average chlorophyll concentrations in the month of November, when the first fertilization and irrigation occurs in the wheat cycle, appear to be "significantly higher" than in the month prior, according to data between 2002 to 2021 from the MODIS instrument aboard NASA's Aqua satellite.

A shoebox-size satellite that NASA began using this year, called the SeaHawk, also captured a portion of the Bahía del Tóbari this November, after irrigation in the valley. Elevated chlorophyll levels could be seen stretching far out to sea, which Feldman described as "remarkable."

"It sure as heck looks like something big is pouring out of that bay," he said.

This proliferation of phytoplankton can drive down oxygen levels in the water creating "dead zones" where sea life cannot survive.

"If there's an overstimulation of phytoplankton because of excess nutrient runoff, it's not going to be a good thing," Feldman continued. "If I happen to be a clam that can't move, I'm dead. And if I'm a crab or a snail and I can't get out of the way fast enough, I die."

The outflows also prompt what's known as "indirect" emissions of nitrous oxide, which can surge in low-oxygen conditions. Scientists suspect that governments are badly underestimating how much nitrogen gets released downstream of agricultural operations. In the Midwestern United States, another over-fertilized nitrous oxide hot spot, research by Timothy Griffis and his colleagues at the University of Minnesota found such emissions could be three times more than typical estimates.

"If you only measure it from the fields, you're only getting part of the story," said Keith Smith, an expert on nitrous oxide at the University of Edinburgh.

A 2019 study of agrochemical pollution in the valley's waterways found elevated levels of mercury, lead and chromium in the sediments flowing from the drainage canals into the Bahía del Tóbari and in the fish and mollusks found there. Earlier research has also documented widespread contamination by pesticides such as DDT and related chemicals in samples of blood and breast milk of people living in the area.

The fishermen of Paredón Colorado, a beachfront village along Bahía del Tóbari, live with the fertilizers, pesticides, tractor tires and other farming detritus that flush out of the canals, and they are familiar with the costs of this pollution. They say the chemicals have depleted populations of fish and shrimp.

"The pesticides, the herbicides, the fertilizers, all of it flows into the sea. And all of it affects us," said Manuel Diaz Lopez, a 68-year-old fisherman and member of the village cooperative. "Everything pours off the shore and the species die."

"I remember when I was 10 years old, the boats would come back with 200 kilos of shrimp. Now, they're getting 10 or 20 kilos in a day."

- - -

In the absence of detailed field measurements, Mexico and many other countries, mostly in the developing world, use a crude calculation to quantify the amount of nitrous oxide they release into the atmosphere. They estimate that 1% of nitrogen fertilizer applied becomes nitrous oxide - a default "emissions factor" set by the U.N.'s Intergovernmental Panel on Climate Change (IPCC) in 2006.

But recent scientific models suggest those estimates are not in line with reality. In major food-producing countries, researchers have found large gaps between reported nitrous oxide emissions and those calculated by atmospheric models, including in Mexico, Brazil and India.

The country's emissions could be up to 4.6 times higher than what it has acknowledged in the past, according to a study done by Philippe Ciais of France's Laboratory of Climate and Environmental Sciences, along with several colleagues.

Hanqin Tian, a researcher at Auburn University who specializes in nitrous oxide, reviewed Mexico's emissions for The Post. He analyzed independent data sets that track emissions by countries and "process-based models," which track nitrogen in its various forms as it makes its way through Earth's ecosystem. This analysis, too, suggests Mexico's agricultural emissions of nitrous oxide are too low in the country reports.

Mexico's Agriculture Ministry acknowledged its numbers probably are an undercount.

One of the reasons for this "apparent underestimation" in Mexico's last official report to the United Nations was a reliance on the calculation set by the IPCC that assumes a linear relationship between fertilizer use and emissions, said León Zaragoza, the Agriculture Ministry spokesman.

He said more nuanced calculations, involving fertilizer dose and farmland surface area, were used in a 2019 government estimate. But in that update, the country's reported emissions only rose by approximately 4%.

As for why some analyses produce much higher emissions totals, León Zaragoza noted, "nonlinear modeling yields emission data higher than linear ones."

Ortiz-Monasterio's research helps explain some of the disparity. In a 2018 paper, he and several colleagues documented that when doses of fertilizer are increased, nitrous oxide emissions begin to rise along an exponential curve.

"As long as you're applying under what the crop needs, the emissions are mild," he said. "It really jumps up once you start applying more than the crop needs."

Growing plants need only so much nitrogen before they're sated. Then the microbes, which had previously been competing with the plants for their nutrients, begin to feast. Scientists have documented this in field studies by adding more and more nitrogen to plots of cropland and measuring the resulting emissions.

The exponential rise "always coincides with the point at which there is so much nitrate that the plant growth won't be stimulated any more," said Philip Robertson, an agricultural scientist at Michigan State University who has worked with Ortiz-Monasterio analyzing the Yaqui Valley.

The warming climate makes things worse. Hotter temperatures, especially during the non-growing season, accelerate the microbes producing nitrous oxide. Drought conditions can also stunt plant growth leaving more fertilizer unused.

In a 2019 study, Rona Thompson of the Norwegian Institute for Air Research and her colleagues measured nitrous oxide in the air in spots around the globe, combined with atmospheric models to map how winds move the gas. They calculated that the true emissions factor could be nearly twice as high as the 1% set by the IPCC.

"If you use just a global default emissions factor everywhere, you will underestimate the [nitrous oxide] emission, especially in areas where there is very intense nitrogen fertilizer usage," Thompson said.

These results help explain the rapidly increasing concentration of nitrous oxide that has been measured in the atmosphere in recent years.

- - -

Fernando Esquer Rochin leaned against his pickup truck and watched the dust rising behind the weathered, blue Ford tractor. He is a supervisor at Agrocasa, the fertilizer supplier and part of the agricultural consortium called Grupo Cajeme that farmed parcels throughout the valley. These farmers had generations of experience but still relied on relatively rudimentary tools - with none of the satellite-monitored, laser-guided technologies used by competitors in wealthier countries.

But Rochin knew what happened when fertilizer was spread unevenly - ugly islands of yellow marring a sea of green wheat - and his job was to make sure Carlos Antonio Gaxeola and the other young farmworkers used enough fertilizer, and that the tractor scattering it followed a straight line.

"There isn't money for a GPS," he said.

That November morning, Gaxeola had signed the receipt for a delivery of 10,070 kilos of fertilizer, enough to cover 20 hectares. They were using a mixture that was typical for the valley: four parts urea, which looked like small, white hailstones, and one part phosphorous, a grayish pebble. The farming associations buy fertilizer in bulk from brokers who arrange for its delivery from major exporters such as China and Russia and it arrives in August on container ships in port towns such as Topolobampo.

The quantity that the workers applied amounted to 200 kilos of nitrogen per hectare - more than CIMMYT researchers considered advisable in a year. And this was just the first fertilization of the season.

Nitrous oxide emissions were not high on Rochin's list of worries. The valley had endured two years of crippling drought, so extreme that local authorities the month before had sharply restricted planting corn - an important secondary crop for the valley, and lately the most profitable one - because reservoir levels had fallen so dramatically.

Gaxeola, 22, had shown up that morning with a goose egg on his forehead after being jumped in a bar fight the night before. It was not uncommon, he said, to see convoys of narcos in pickup trucks roaring down these rural roads. The local gangs would steal whatever they could - tractors, tires, even the massive tanks of anhydrous ammonia fertilizer marked with warnings "peligro" and "gas tóxico"- if left in the fields too long. Fertilizing needed to be quick.

"Many of our partners, because of the insecurity that we're living through right now, prefer to do all the fertilizing before planting," Rochin said.

Rochin had seen other farmers experiment with reducing nitrogen through organic practices, manures, infrequent tilling - and he found them lacking. The Yaqui Valley had been industrially farmed for a century and the soil was depleted. To him, using less fertilizer wasn't an option.

"For the environment, it would be less harmful, but yield would be very low," he said. "Low fertilizer, low production."

Wheat is sold by the ton and so yield - the weight of the grains that gets harvested - is the ultimate priority for those who make their living from the land. Even small declines in the weight of wheat can turn profit into loss. Farmers and agronomists are continuously crossbreeding varieties to find wheat that weighs more, needs less water and is resistant to disease.

During the first week of May, as the harvest was in full swing across the valley, a few dozen farmers, agronomists and government researchers gathered under a white tent at the edge of a wheat field to learn what their future might hold. A thresher was harvesting samples of the newest genetic strains. The atmosphere of the annual test was festive - tacos were served on flour tortillas, and young women with clipboards and straw hats tallied results on an easel.

The experimental varieties had been developed by CIMMYT scientists and the tests were conducted by Agriculture Ministry officials to precise specifications. Each type of seed was planted in 12 rows that were 444 meters long and separated by 80 centimeters. The grains were harvested and weighed for all to see, so farmers would trust the outcome. It would be years before any of the seeds would become widely used across the valley, but the results that day were promising.

"These are better than the varieties we have," said Alberto Borbón-Gracia, a government researcher. "And by a lot."

It was a rare bit of good news amid increasingly dire conditions for those trying to make a living off the land. The record-breaking drought fanning wildfires and emptying reservoirs across the American West have been just as painful for Sonora. On the ranches in the hills above the Yaqui Valley, thousands of cattle have died of starvation or been slaughtered prematurely as grasses shriveled in the heat.

Three decades ago, it was common for farmers to harvest two crops per year - soybeans in the summer and wheat in the winter. There is no longer enough water for that. So the soybeans, which helped absorb nitrogen that might otherwise be lost, were phased out.

"The principal worry we have is drought," said Álvaro Bours Cabrera, the head of the largest farming association in the valley, which produces a quarter of Sonora's wheat. "We've always battled against years with shortages of water. But we are seeing those more continually, frequently."

Wheat needs a certain number of cold nights in the winter to thrive. But those lows have softened over time. Between 1960 and 2019, minimum temperatures in the growing season of January to March rose 1 degree Celsius. This resulted in farm yields that were 7% lower than they otherwise would have been, according to a recent study.

During the wheat testing event, Juan Manuel Cortés-Jiménez helped record the results. He has watched farmers struggle to adapt to a changing climate over the past 37 years as an investigator with Mexico's Agriculture Ministry.

He bristled at the notion that Mexican farmers could be blamed for emissions when major emitters are not fixing the problem, or when leaders such as former U.S. president Donald Trump are dismissing climate change entirely.

"What's going to happen with the world if the principal producers of greenhouse gases say that climate change is a lie? What signal does that send?" he said. "For people who don't read scientific journals, if they hear the Americans say there's no problem with this. Why do we have to do something about it down here?"

- - -

In 2002, Ortiz-Monasterio and colleagues at Oklahoma State University introduced farmers to an innovation called a GreenSeeker - a handheld sensor that measures a wheat plant's chlorophyll levels and recommends an optimal amount of nitrogen.

For eight years, the state and federal government helped fund the program, paying for technical advisers to take measurements and make fertilizer recommendations. Over that period, farmers working on a total of 48,000 hectares of land signed on. It seemed a rare win-win: The tool added $1.8 million to farmers' profits, while cutting greenhouse gas emissions by 9,600 tons of carbon dioxide equivalent, akin to taking 2,000 cars off the road, according to an analysis of the program by RTI International, a nonprofit research group.

But in 2015, after a year in which low wheat prices and unusually bad weather hammered profits, farm associations pulled financial support for the GreenSeeker program, and public funding dried up as well. If farmers wanted sensor readings, they had to pay. Participation plummeted.

Now, only a handful of farmers still use the sensor. In the offices of one farming association, its GreenSeeker is stored next to the toilets, an unused relic.

"It sounds incredible, but it's true," said Bours, the farming association president. "A program that could help the producer save a lot and we're not taking advantage of it."

Credit bureaus haven't helped. For many farmers to secure loans and insure their crops, they must over-fertilize. Bours acknowledged that his association still encourages over-fertilization, even with fertilizer prices "out of control," as a way to minimize risk.

"They are afraid it will be a lost year, a bad harvest. And that means losing a whole year of income," said Jose Alfonso Salido, a third-generation farmer who has worked with Ortiz-Monasterio using sensors affixed to drones to measure the color of wheat and its nitrogen needs. "The biggest problems we have is that farmers don't want to worry - with too much fertilizer, they can relax, but it's not what the plant needs."

"As one farmer told me, 'I put on 180 units of nitrogen as fertilizer,' " Ortiz-Monasterio said. " 'And later, I added 60 more as a tranquilizer.' "

Luis Arturo Amaya is one of the few farmers who still uses the GreenSeeker sensor to find the optimal level of fertilizer. His grandfather helped Borlaug reproduce wheat seeds for his experiments. His father worked with Ortiz-Monasterio and other CIMMYT scientists.

Amaya, 48, approaches his work managing 300 hectares with a tinkerer's curiosity and an appreciation for science. And until Mexico's government regulates fertilizer use, the process used by this third-generation farmer may be the only viable way toward lowering nitrous oxide emissions.

"Do you smell that?" Amaya asked. "That's chicken dung."

Amaya uses alternatives to synthetic fertilizer when possible, including "gallinaza," which leaves a coating of white feathers over the dirt. He practices low-till and organic techniques that require less nitrogen. He takes soil samples for laboratory analysis. On some plots, Amaya experiments with rare varieties of wheat, including one from the time of the Spanish missions in the 17th century, and another common in the valley before Borlaug arrived.

Unlike others who stubbornly pursue yield, Amaya's goal is to maximize margin. Particularly in years like this, with fertilizer prices twice as high as last year, he looks for any chance to cut costs. Yet even for him, a farmer attempting to sell to niche markets of restaurants and artisanal bakers, these alternatives cannot wholly replace synthetic fertilizers due to cost and manpower.

"After working all these years trying to transfer this one technology, that's when I realized that we need policy," said Ortiz-Monasterio. "If we really want to make a change, we need policy."

Mexico's populist president, Andrés Manuel López Obrador, who once campaigned on relocating the Agriculture Ministry to the Yaqui Valley, cut federal subsidies to farmers here when he took office, further eroding federal influence on their planting and fertilization decisions.

His administration "has decided to support with incentives the poorest farmers in Mexico, who had been left unattended," said León Zaragoza, the ministry spokesman. "The high-input farmers of the Yaqui Valley do not fall into this category."

Instead of subsidies or regulation, León Zaragoza said that federal funding supports CIMMYT and other organizations so they can try to convince farmers to adopt the sensors, drones and other technology for more efficient nitrogen use.

"There is excessive use of nitrogen fertilizers in wheat production in the Yaqui Valley," León Zaragoza said. These farmers "should apply less nitrogen fertilizer and that is why we have supported institutions such as CIMMYT for the development of diagnostic tools."

And so Ortiz-Monasterio will continue to spread the gospel of efficient nitrogen. His goal is not a fertilizer ban, but rather better management: applied in the right amount, at the right time, so the plant gets what it needs and not more.

He hopes he'll find the next generation more attuned to the contamination in the water supply, the algae in the Sea of Cortez and the invisible dangers of nitrous oxide.

"It's very difficult to change the mind of a 60-year-old person who's been farming for the last 40 years, and pretty much thinks he knows everything," he said. "The guys who are willing to adopt these changes are the younger guys who are replacing their parents. They're a lot more open to change."

- - -

Mooney reported from Washington D.C.

---

Video Embed Code

Video: http://www.washingtonpost.com/video/climate-environment/an-exponential-rise-in-nitrous-oxide-emissions/2021/12/22/8e8ea5b5-f6ee-4d8d-9496-1c2ddea40961_video.html(REF:layj,REF:sarkisovad,REF:partlowjf/The Washington Post)

Embed code: <iframe src="https://www.washingtonpost.com/video/c/embed/8e8ea5b5-f6ee-4d8d-9496-1c2ddea40961?ptvads=block&playthrough=false" width="480" height="290" data-category-id="video-elements" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe>