When a cloud of volcanic ash from Iceland shut down air travel in Europe in April, news media scrambled for volcano experts.

Soon, both the Wall Street Journal and CNN were quoting and chatting with a man who gave the location of his research facility as Apache Junction.

Robert "R.B." Trombley directs the International Volcano Research Centre, where he is also listed as lead volcanologist on the center's website. It bills itself as an organization that conducts volcanic analysis, eruption forecasting and public education.

On April 16, Trombley was quoted in the Wall Street Journal on the potential for acid rain. If a volcano's ash has a high concentration of sulfur, it can mix with water vapor to form sulfuric acid. "It's hard to say whether that's a problem right now," Trombley said.

Three days later, Trombley appeared on CNN's "American Morning," discussing the volcano's effect on the airline industry as test flights were launched into the ash cloud.

According to a transcript of the show, Trombley said: "I think the test flights are good. I'm an ex-pilot myself, so I'm used to listening to these type of scenarios. . . . I understand their need for precaution on the safety side, but as things look like they're OK, then I think they can resume the flights."

Pay a visit to Trombley's research center, however, and the story of Arizona's volcano expert turns into a cautionary tale about how the media's push for instant news coverage can sometimes lead to experts with questionable credentials.

The International Volcano Research Centre is located in Trombley's home, a pink trailer in Apache Junction.

It's the place where Trombley says he monitors online data from more than 500 volcanoes each day and then assesses their likelihood of eruption through a software program he says he designed.

On a recent morning, broken glass glistened by the front door as nearby traffic roared past on U.S. 60. The Superstition Mountains, said to be remnants of a volcano 18 million years ago, rose in the distance.

Trombley's website, www.intlvrc.org, contains a list of current eruptions; a description of fee-based services and products, such as community presentations and CD-ROMs of past volcano expeditions; and links to the reports and papers by Trombley and his staff.

Included is his resume, which contained a discrepancy that he dismissed as an oversight in an interview with The Arizona Republic.

It said he received his Ph.D. in astronomy from the University of Dallas in 1974. The registrar's office said Trombley was never registered at the private Christian school, nor has the school ever offered such a degree.

When confronted about the school's response, Trombley told The Republic his doctorate actually came from Dallas State College.

He appeared surprised that the University of Dallas had been listed and then said he graduated from Dallas State, adding that he wasn't sure "if it's even open now."

The same year Trombley received his doctorate, then-Texas Attorney General John Hill alleged Dallas State College was a "diploma mill" that sold diplomas and degree transcripts for fees ranging from $75 for a high-school diploma to $180 for a Ph.D.Since Trombley's interview with The Republic, his resume has been corrected.

In 1975, a Texas District Court in Dallas permanently prohibited the college from operating in the state for violating the Deceptive Trade Practices Act.

A spokesman for the Texas Higher Education Coordinating Board said recently that all degrees from Dallas State College are void.

Trombley's resume also lists a bachelor's degree in law, cum laude, from LaSalle Extension University in Chicago in 1973, just a year before completing his Ph.D.

LaSalle was a program for studying at home. In 1978, the Federal Trade Commission required LaSalle to issue a disclaimer saying that no state accepts any home law course "as sufficient education to qualify for admission to practice law."

LaSalle Extension University is not accredited with the American Bar Association. To practice law in the U.S., a law degree from an ABA-accredited institution is one of several requirements.

Trombley spent time teaching at DeVry University in Phoenix, a for-profit college offering degrees in business, technology and multimedia. He was remembered by staff as a knowledgeable man who told interesting stories about his volcano expeditions.

A company spokesman confirmed Trombley was a full-time faculty member from July 1993 to August 2000, teaching algebra, statistical analysis and program management.

He also taught a non-credit class earlier this year for the Central Arizona College Lifelong Learners program designed for retirees. The class - "Volcanoes: What, Why, Where and How" - was a lecture series.

Tom DiCamillo, a CAC spokesman, said the Lifelong Learners classes are typically taught by community members with a particular knowledge base.

Volcanologists recognized in their field have questioned Trombley's credentials and his methodology.

In 2009, Jonathan Fink, a longtime professor at Arizona State University and director of its Center for Sustainability Science Applications, warned the more than 2,000 subscribers to his Volcano Listserv about Trombley's eruption forecasts.

"To our knowledge, Dr. Trombley does not have training as a volcanologist, and his previous reports have raised concerns among a number of volcano practitioners and organizations . . . about the possibility of misinterpretation," Fink told his subscribers by e-mail.

Trombley developed a computer program estimating the probability that a volcano will erupt based on widely available seismic data. He said his program, Eruption Pro 10.7, has forecast 41 of 43 eruptions this year.

The results can be used in a variety of ways, he said: World relief agencies may use the data to plan, and oil companies could use it to adjust their operations. Trombley said companies, countries, universities and the National Weather Service utilize the information.

Matt Oca�a, a Weather Service spokesman, said he checked with his colleagues at the agency and at the U.S. Geological Survey, which provides volcano data. They had not heard of Trombley, his center or Eruption Pro.

Fink told The Republic that Trombley has been a "somewhat controversial figure in volcanology, making forecasts based on statistical methods that others have not been able to replicate." Fink said he thinks that if Trombley were to publish work in peer-reviewed literature, it would "go a long way to quieting his critics."

Trombley said his work has been peer-reviewed and told The Republic he was published in Eos, a publication of the American Geophysical Union. No work bearing Trombley's name could be found in a search of AGU's archives.

Bill Rose, a volcanologist and professor of geological engineering and sciences at Michigan Tech University, said in a recent e-mail, "Anyone can say they are a volcanologist. . . . He (Trombley) seems 'all hat and no cattle.' "

Trombley said he didn't know how to answer critics.

He explained that, although he doesn't have a degree in volcanology or geology, traditional courses of study for volcano experts, astronomy is similar and that he has learned through experience.

"I don't have a degree in geophysics or geology, per se, but it's like I'm so close," Trombley said. "I've worked in the field so long and been to so many different volcanoes and stuff, that, you know, I haven't found one thing I've said yet that hasn't been true."

How did major media end up using a volcano enthusiast with no recognized formal education in the subject as an expert commentator?

The Wall Street Journal reporter did not return calls for comment.

A CNN spokesperson released this statement: "As with all our guests, CNN extensively researches their qualifications prior to putting them on our air.

"We found Dr. Trombley to be a knowledgeable volcanologist who could help shed light on the eruptions in Iceland.

"Dr. Trombley is the director and principal research volcanologist at the International Volcano Research Centre, as indicated on the website for Central Arizona College, where he is a professor who teaches volcanology. For these reasons, we booked him as a guest on the topic."

The Republic ran a profile of Trombley's center in 2006 but did not ask for an expert opinion.

Roy Peter Clark, senior scholar at the Poynter Institute, a journalism school and resource center in St. Petersburg, Fla., said, "This has always been a problem in journalism."

He said there are people "who kind of flip though the filters, sometimes because they just seem to be everywhere. In other words, they're quoted, and you think that maybe somebody has gone through the process of checking out their credentials."

Clark said checking credentials may be one of the journalist's most important jobs.

In the meantime, Trombley and one of his volcano technicians are headed to the Caribbean island of St. Lucia this month to conduct experiments at several volcanic sites.