by Judith Curry
Perhaps my experience in studying the Earth, initially with few restrictions and later with increasingly sophisticated interaction with government sponsors and various planning committees, will provide a perspective on this great transition from science being primarily an intellectual pastime of private persons to its present status as a major contributor to the quality of human life and the prosperity of nations. – Charles Keeling
Most of you are familiar with Charles Keeling. An overview of Keeling’s accomplishments is given in this NYTimes article:
But the essence of his scientific legacy was his passion for doing things in a meticulous way. It explains why, even as challengers try to pick apart every other aspect of climate science, his half-century record of carbon dioxide measurements stands unchallenged.
By the 1950s, when Dr. Keeling was completing his scientific training, scientists had been observing the increasing use of fossil fuels and wondering whether carbon dioxide in the air was rising as a result. But nobody had been able to take accurate measurements of the gas.
As a young researcher, Dr. Keeling built instruments and developed techniques that allowed him to achieve great precision in making such measurements. Then he spent the rest of his life applying his approach.
Throughout much of his career, Dr. Keeling was cautious about interpreting his own measurements. He left that to other people while he concentrated on creating a record that would withstand scrutiny.
The motivation for this post comes from someone emailing me this autobiographical essay by Charles Keeling: Rewards and Penalties of Monitoring the Earth [Keeling_autobiography].
Abstract: When I began my professional career, the pursuit of science was in a transition from a pursuit by individuals motivated by personal curiosity to a worldwide enterprise with powerful strategic and materialistic purposes. The studies of the Earth’s environment that I have engaged in for over forty years, and describe in this essay, could not have been realized by the old kind of science. Associated with the new kind of science, however, was a loss of ease to pursue, unfettered, one’s personal approaches to scientific discovery. Human society, embracing science for its tangible benefits, inevitably has grown dependent on scientific discoveries. It now seeks direct deliverable results, often on a timetable, as compensation for public sponsorship. Perhaps my experience in studying the Earth, initially with few restrictions and later with increasingly sophisticated interaction with government sponsors and various planning committees, will provide a perspective on this great transition from science being primarily an intellectual pastime of private persons to its present status as a major contributor to the quality of human life and the prosperity of nations.
Some excerpts from Keeling’s essay:
Science in spite of politics
From the prologue:
At editorial request, the following sketch is focused on a particular aspect of my career: my desire to measure atmospheric carbon dioxide. For much of my professional career, this desire met with heavy opposition from certain agencies of the US Government that wanted such measurements to be managed principally, or even solely, as in-house programs of the federal bureaucracy. I have attempted to intertwine the portrayal of this struggle with a narrative of the concurrent gain in knowledge from my measurements which repeatedly helped me to argue for their continuance.
In one of the summary sections, Keeling writes:
SCIENCE IN SPITE OF POLITICS Why Go On? Through the long years of my disagreement with government agencies on whether or not I should be measuring atmospheric CO2, many people wondered why I tried so hard to stay involved. I will now attempt to explain, although in some respects I’m not really sure. First, my enthusiasm to study atmospheric CO2 never slackened; it depended, however, on acquiring data that truly reflected nature. The international CO2 monitoring program of WMO, although originally organized by scientists, was soon mainly under the control of meteorological agencies.
After agency managers began to assert that the acquisition of CO2 data, like the acquisition of weather data, was to be regarded as routine rather than a pursuit of basic science, I wondered what might happen to data quality over time. I hadn’t forgotten that the CO2 measurements published in Tellus before I began my studies had been terribly wrong but were generally regarded as valid until new data proved them wrong. I wanted to remain directly involved in CO2 data gathering to be able to judge the quality of such data on my own terms. Moreover, those recruited to inaugurate NOAA’s CO2 program set about removing what I felt to be safeguards in the procedures that I had adopted to assure valid data. Then these newcomers gave out an impression that measuring atmospheric CO2 was relatively problem-free, whereas I had had difficulty sustaining high-quality measurements over long periods.
To add to my apprehensions, the official in NOAA most responsible for opposing my program had a reputation for after-the-fact apologies when data under his supervision had turned out to be less than satisfactory. The most compelling reason for my wishing to stay involved was that the data gathered in my program became more and more fascinating as the records lengthened.
A broader perspective on this issue is written in an essay at aip.org from Spencer Weart, entitled Money for Keeling: Monitoring CO2 levels.
This is a story with scary implications. Had Keeling not stayed involved with monitoring CO2 levels, the scientific debate surrounding CO2 and climate would be substantially muddier than it is now.
When I read this saga, I see the same problems currently with the federal funding agencies. The most analogous example to Keeling’s saga is the ISCCP saga – the International Satellite Cloud Climatology Project (discussed in this recent post). There has been no ISCCP analysis of clouds since 2009, as NOAA is trying to ‘operationalize’ the production of the ISCCP analysis. Once the logistical issues of doing this are finally ironed out, the big question is whether the overall dynamic quality (in terms of ongoing improvements and assessments) established by Bill Rossow (originator of ISCCP) will continue.
Buried in my pile of draft posts is one entitled ‘Who’s calling the shots?’, which addresses the control that federal program managers have over what science gets done not only in government labs, but also universities. For another time.
Views on AGW
Keeling writes of his views, circa 1969:
In 1969, I spoke on invitation before the American Philosophical Society on the implications of rising atmospheric CO2. This rise was of interest, I said, because if it persisted it was likely to inhibit the escape of heat radiating upward from the Earth’s surface and bring about a warmer climate—the socalled “greenhouse effect,” although I didn’t use that expression.
The remainder of my talk was inspired by my having helped to write a report for the President’s Science Advisory Council. Roger Revelle, the lead author of the report, was struck by the fact that the human race was returning to the air a significant part of the carbon that had been slowly extracted by plants and buried in sediments during a half billion years of Earth history. He thought that measurable, perhaps even marked, changes in climate might occur from an increasing greenhouse effect. He believed that careful measurements should be made to check such predictions.
Echoing Revelle’s concern before the American Philosophical Society, I too pondered the significance of returning a half a billion years’ accumulation of carbon to the air . I appreciated his concern because of direct personal experience, watching CO2 rise from near the oft-stated background level of approximately 300 ppm (0.03%) to over 320 ppm. I wondered what the consequences of rising CO2 would be in, say, 30 years:
“The rise in CO2 is proceeding so slowly that most of us today will, very likely, live out our lives without perceiving that a problem may exist. But CO2 is just one index of man’s rising activity today.We have rising numbers of college degrees, rising steel production, rising costs of television programming and broadcasting, high rising apartments, rising numbers of marriages, relatively more rapidly rising numbers of divorces, rising employment, and rising unemployment. At the same time we have diminishing natural resources, diminishing distract-free time, diminishing farm land around cities, diminishing virgin lands in the distant country side… .
I noted in closing my talk that people held widely divergent views concerning a possible peril attending rising CO2, but that in 30 years “if present trends are any sign, mankind’s world, I judge, will be in greater immediate danger than it is today.” As it happened I would have little leisure time to pursue such philosophical thoughts during the next 30 years.
His views 30 years later:
It has been over 30 years since I speculated before the American Philosophical Society that the world by the end of the 20th century might be in greater danger from rising CO2 than itwas in 1969. Where do we stand on this issue today?
My friend Bert Bolin, joined by others around the world, a few years ago started a political process drawing attention to possible dangers of rising CO2 and urging that the use of fossil fuels be scaled back, or at least stabilized. Governments worldwide have recently tried to initiate this stabilization process, meeting in Kyoto, Japan, to agree on thewording of an international treaty to restrict fossilfuel use. I have not been a part of this political process, but I would like to add here a few thoughts on whether rising CO2 and attending climate change, especially possible global warming, should be viewed with concern.
Not everyone agrees that there is a global-warming problem. There are probably even some who doubt that atmospheric CO2 concentrations are rising. Not long ago, while attending a scientific conference on climate, I encountered a meteorologist employed by a utility company who was examining a poster showing a curve of rising atmospheric CO2 labeled “Mauna Loa Observatory.” He was pointing out to the author of the poster that one should be cautious about interpreting this curve because of a steady increase in local automobile traffic near the observatory. I could not fault him for raising this concern, because I was at the time protesting to NOAA a lack of control over this increasing traffic, but he should have acknowledged that CO2 measurements at other sites, with no possibility of local contamination, corroborated that the rate of rise seen in the Mauna Loa record was global.
Should scientists attempt to help the public to understand better the significance of rising CO2 and the global warming issue? Understandably, many do not wish to take a position regarding a possible peril associated with these issues. Even to publish scientific findings that suggest a peril in rising CO2 or temperature can be construed as taking a prejudicial position.
A safe approach is just to remain an interested observer of the unfolding scientific evidence of man-made global change and its possible significance to future human welfare. Without risk one can comment dispassionately on sociological, political, and religious perspectives of the global warming issue, for example, as an historian might, beginning with the first hints of man-made global change and progressing toward the time, not yet arrived, when there may be convincing proof of global warming.
I believe, however, that a more prudent attitude would be to heed the rise in atmospheric CO2 concentration as serious unless proven to be benign. If scientists would make clear to the public the wisdom of this cautious approach, people would demand to be better informed about what scientists already know. The collective talent and wisdom of a species self-named Homo sapiens might then be better directed toward the issue of global warming.
Meanwhile, what about at least monitoring what is happening to our environment to prepare for possible change? It has been over 40 years since Roger Revelle and Hans Suess pointed out that the burning of fossil fuels was a large-scale geophysical experiment that “if adequately documented may yield a far-reaching insight into the processes determining weather and climate.” There was no sense of peril then, just a keen interest in gaining knowledge. Now, four decades later, there is a hint, perhaps more than a hint, of peril. Nevertheless, and despite the heightened political awareness of the greenhouse problem indicated by the Kyoto meeting last winter, most governments have shown little heightened interest in environmental monitoring.
An interesting postscript on this in the NYTimes article in 2010 (5 years after Keeling’s death):
In an interview in La Jolla, Dr. Keeling’s widow, Louise, said that if her husband had lived to see the hardening of the political battle lines over climate change, he would have been dismayed.
“He was a registered Republican,” she said. “He just didn’t think of it as a political issue at all.”
Natural climate variability
Keeling was very interested in natural climate variability:
Following Bert Bolin’s and my analysis of a global “snapshot” of atmospheric CO2 in 1963, my interest turned to the ever lengthening time-series of CO2 observations at Mauna Loa Observatory and the South Pole. As I have already explained, these records by 1972 were long enough to see evidence that CO2 varied on a decadal time scale in a manner that couldn’t be explained by emissions from fossil fuel combustion. I wanted to acquire the most trustworthy data possible, for as long as possible, to study such subtle effects.
Meanwhile, in 1983 we experienced a partial breakthrough in understanding the relationship of El Nino events to atmospheric CO2, discovered nearly ten years earlier by Bacastow.
It was time to take a further look at variations in the atmospheric CO2 records on the decadal time scale. The gradual slowdown in the rate of rise of CO2 at Mauna Loa and the South Pole in the mid-1960s, and the subsequent more rapid rise in the early 1970s, had been followed by two more such slowdowns and rises. With our records now 30 years long, these fluctuations looked like a repeating decadal oscillation. Was the cause oceanic or terrestrial? Did El Nino events in some way contribute? Our quest to find out led us, however, well beyond our original focus, because once again we found a surprising relationship between CO2 and temperature.
Our curiosity was now drawn towards what could be causing approximately 10-year fluctuations in temperature. We turned our attention to exploring a possible tidal connection with temperature, encouraged by a relevant discussion in the same treatise on climate where Bacastow had discovered the Southern Oscillation. Also, in an article by Loder & Garrett we found mention of a plausible mechanism: that strong tides may cause vertical mixing of stratified surface ocean water with cooler deeper water, sufficiently to cause appreciable transient cooling at the sea surface.
Periodicities abound in the astronomical forcing of oceanic tides by the Sun and the Moon, but to our surprise the only nearly decadal periodicities in tidal forcing that we found were at 9.3 and 10.3 years, very close to the spectral periods that we had found for temperature. Moreover, these two periodicities reinforced each other near 1880 and 1970 but cancelled each other out near 1920, as did the spectral oscillations in temperature. Most surprising, a 6.0 year tidal periodicity replaced the cancelled out decadal periodicity in the 1920s and 1930s; it was phased such that, by causing periodic cooling, it might explain the 6-year fluctuations in temperature seen in our decadal spline curve from about 1920 to 1940. We had perhaps found a plausible tidal mechanism that could explain all of the main features of our band-pass temperature curve. Encouraged by this success, we began to look for additional features of global temperature that might be explained by an hypothesis that strong tides cause cooling of surface sea water.
During times of this strong decadal forcing, from about 1870 to 1910, and again from about 1950 to 1980, the stiffest temperature spline showed no overall warming. In contrast, from about 1920 to 1940, when this strong forcing gaveway to weaker 6-year forcing, the stiffest spline shows pronounced warming. The coincidence of this warming trend with 6-year fluctuations in temperature was striking, as though both features were related to the weaker tidal forcing. Beginning in the late 1970s decadal fluctuations have been accompanied by overall warming, in violation of our tidal hypothesis, but this warming could reflect an enhanced greenhouse effect beginning measurably to affect global temperature.
JC note: While the issue of tidal influences on decadal to century scale climate change remains largely unexplored, Walter Munk has done some very provocative work on this topic, perhaps a good topic for a future post.
JC reflections
I’m surprised I haven’t come across Keeling’s essay previously, it deserves to be discussed. Keeling died in 2005, just before the hyper politicization of AGW (following Al Gore’s movie and the AR4).
I found it very refreshing to read Keeling’s essay, and I find myself wondering what would Charles Keeling have to say about the state of the climate science debate, the politicization of the science, not to mention the temperature hiatus.
Keeling regrets that he didn’t have more time for ‘philosophizing'; but he has provided us with some important insights on this great transition from science being primarily an intellectual pastime of private persons to its present status as a major contributor to the quality of human life and the prosperity of nations.
Filed under: History, Scientific method, Sociology of science