In his position as Chair of the House Committee on Science, Space, and Technology, Texas Congressman Lamar Smith has spent much of the last few years pressuring the National Science Foundation to ensure that it only funds science he thinks is worthwhile and “in the national interest.” His views on what's in the national interest may not include the earth sciences, as Smith rejects the conclusions of climate science—as we saw first hand when we saw him speak at the Heartland Institute’s climate “skeptic” conference earlier this year.

So when National Oceanic and Atmospheric Administration (NOAA) scientists published an update to the agency’s global surface temperature dataset that slightly increased the short-term warming trend since 1998, Rep. Smith was suspicious. The armada of contrarian blog posts that quickly alleged fraud may have stoked these suspicions. But since, again, he's the chair of the House Committee on Science, Space, and Technology, Rep. Smith was able to take action. He's sent a series of requests to NOAA, which Ars obtained from Committee staff.

The requests started on July 14 when Smith wrote to NOAA about the paper published in Science by Thomas Karl and his NOAA colleagues. The letter read, in part, “When corrections to scientific data are made, the quality of the analysis and decision-making is brought into question. The conclusions brought forth in this new study have lasting impacts and provide the basis for further action through regulations. With such broad implications, it is imperative that the underlying data and the analysis are made publicly available to ensure that the conclusions found and methods used are of the highest quality.”

Rep. Smith requested that NOAA provide his office with “[a]ll data related to this study and the updated global datasets” along with the details of the analysis and “all documents and communications” related to part of that analysis.

In the publication at issue, the NOAA researchers had pulled in a new, larger database of weather station measurements and updated to the latest version of an ocean surface measurement dataset. The ocean data had new corrections for the different methods ships have used over the years to make temperature measurements. Most significantly, they estimated the difference between modern buoy stations and older thermometer-in-a-bucket measurements.

All the major temperature datasets go through revisions like these, as researchers are able to pull in more data and standardize disparate methods more effectively. Since NOAA’s update, for example, NASA has pulled the same ocean temperature database into its dataset and updated its weather station database. The changes are always quite small, but they can sometimes alter estimates of some very short-term trends.

NOAA responded to Rep. Smith’s request by pointing him to the relevant data and methods, all of which had already been publicly available. But on September 10, Smith sent another letter. “After review, I have additional questions related to the datasets used to adjust historical temperature records, as well as NOAA’s practices surrounding its use of climate data,” he wrote. The available data wasn’t enough, and he requested various subsets of the data—buoy readings separated out, for example, with both the raw and corrected data provided.

This letter also asked for explanations of the differences between these datasets and “NOAA’s rationale for constructing the datasets as outlined in” the Science paper. The politician reiterated, more specifically, requests for “all documents and communications” relating to several topics. Somewhat ironically, Rep. Smith even invoked the last Intergovernmental Panel on Climate Change report in one letter, describing the NOAA study as being “in direct disagreement” with it.

When NOAA did not respond before Rep. Smith’s two-week deadline, a September 25 letter threatened a subpoena. NOAA apparently provided the data Rep. Smith requested shortly after, but the organization refused to hand over internal communications. The threatened subpoena was sent on October 13.

The subpoena states that NOAA was “asserting a ‘confidentiality interest’ with regard to 'scientific communication' as a reason that communications from federal employees cannot be produced to the Committee. The 'confidentiality interest' cited by NOAA is not recognized by the Committee as a legitimate privilege[…]”

NOAA contends that drafts and deliberative discussions among scientists are confidential and that the publication of data and methods are sufficient. The agency is far from alone in that regard, and the thorny issue of protecting the process of scientific inquiry from quote-mining expeditions has come up before.

NOAA has not indicated how it intends to respond to the subpoena. But last Friday, Texas Congresswoman Eddie Bernice Johnson, who leads the Democrats on the House Committee, issued her own response. She posted a letter sent to Rep. Smith revealing and criticizing his actions. In it, she noted that Rep. Smith was looking into a scientific study and not a Federal policy decision. “As such,” she wrote, “this is not an area of delegated legislative authority by Congress to the Executive (unless you are proposing that Congress should somehow legislatively overrule peer-reviewed scientific findings).”

She continued, “Congress’s oversight powers are broad, but not unlimited. Congress must have a rational basis for its demands.”

Given the persistent requests for internal communications, it’s clear that Rep. Smith is hoping to find some sort of evidence of tampering, though no accusation has been explicitly made. While the NOAA update was ho-hum to most climate scientists, those who placed a great deal of importance on the 1998–2013 surface air temperature trend were threatened by any suggestion that it might be larger than they thought.

Regardless of how Rep. Smith’s subpoena is resolved, 2015 is primed to once again set a global average surface temperature record—and not just in the NOAA’s estimation.