“The more we looked at it, the more obvious it appeared to be an error,” he said.

Mr. Burt brought his blog post to the attention of members of the World Meteorological Organization. Randall S. Cerveny, a geography professor at Arizona State University who holds the title rapporteur of climate extremes for the World Climate Organization, appointed a committee of 13 climatologists, including himself and Mr. Burt, to resolve what can often be tricky disputes.

“There are a lot of places that do like these records,” he said. “It can be a source of pride for that country or a source of contention for other countries. Politics unfortunately is going to play a role sometime in the determining of these records.”

It took a year to investigate the claim — the inquiry was hampered by the revolution in Libya, which resulted in the temporary disappearance of a Libyan scientist who was central to the work. The final report found five reasons to disqualify the Libya claim, including questionable instruments, an inexperienced observer who made the reading and the fact that the reading was anomalous for that region and in the context of other temperatures reported in Libya that day.

“The W.M.O. assessment is that the highest recorded surface temperature of 56.7 degrees C (134 degrees F) was measured on 10 July 1913” in Death Valley, the report said.

The announcement was made on Sept. 11, the same day as the attack on the American diplomatic mission in Benghazi, and thus drew little notice.

Though it is easy to forget on days when it is so hot that people dare not step out of their cars, part of the allure of Death Valley has always been — besides the staggering beauty of its canyons, mountains and sunsets — the sheer challenge of visiting it.