Last Update: 02.25.12
Science and Climate Change
Dr. Robert Williams
Introduction by Dr. Ray Weymann
It is an honor to be able to post the following "Guest Scientist" essay from a renowned astronomer of international stature.
Bob is my oldest and best friend in astronomy and I have known and admired him for 47 years. He joined me on the Astronomy Faculty at the University of Arizona in 1965. He has had a remarkably distinguished career in teaching, research, public outreach and high-level positions in astronomy, including Directorship of the Cerro Tololo Inter-American Observatory and the Space Telescope Science Institute (home of the Hubble Space Telescope) and is currently the President of the International Astronomical Union.
I asked him to write the following essay, not because he is deeply conversant with the ins-and-outs of climate science -- he is the first to tell you he is not -- but because of his reputation for scientific integrity. His essay captures both the fundamental role that science has played in the evolution of our civilization and also the attitudes of openness and objectivity that are the essential ingredients of the true scientist.
Would that these characteristics were shared by all of those commenting on climate science and its societal implications!
Science and Climate Change
There have been two great scientific revolutions in history --- the Copernican and the Darwinian revolutions. The hypotheses and observations of Copernicus and Galileo, and later the observations and ideas of Darwin presented evidence that went against the prevailing thinking of their times. The Copernican revolution took over a century to gain acceptance, and the struggle over Darwin’s ideas continues in many quarters of the world after more than a century and a half. The fact that science often forces us to accept concepts and facts that we initially reject makes it one of the best possible agents of realization. If we accept that prejudice and superstition seem to be instinctive in humans there is no better way to combat their influence than by educating people to scientific thinking.
Science is more than just discovery; it is a process. A process by which one gathers data to test ideas and then modifies them to satisfy the data. The facts that emerge from scientific discoveries are fascinating and revolutionary in terms of the capabilities they provide to the public. The have lead to strong public interest that has created an increasing appreciation for the importance of scientific investigation. This is especially true in the area of terrestrial climate change.
As an astronomer I have rather limited first hand experience with the extensive world-wide research programs on climate that have been going on for some decades. Like every issue that has potential importance to society, whether it involves behavioral or medical or physical science, I read about it and discuss it with friends and colleagues. Like any scientific issue there will be credible and knowledgeable people that take different sides of the debate, no matter what the issue is. For example, the questions of whether the earth revolves around the sun or whether the continents are drifting apart are now widely believed to be understood. Yet, in their time great resistance was given to both ideas, and it took many, many years for these ideas, initially rejected, to be accepted as fact.
The question of human influence on climate change and global warming is following a similar trajectory to the heliocentric solar system and continental drift. The fact that it is difficult to isolate various factors in determining climate, which by definition is a long duration phenomenon, does make it easy to justify contrary opinions on the matter.
What does need to be established in any debate, whether concerning a topic such as continental drift or climate change, is the effect to which self-interest affects one’s conclusions about the issue. As Simon & Garfunkel’s great line from their hit song ‘The Boxer’ goes, “A man hears what he wants to hear and disregards the rest”. This tendency is profoundly human, ..... and profoundly dangerous. It affects scientists as well as anyone. We are not immune.
This does not mean that one should distrust scientific conclusions, but that one must admit to the existence of pre-existing prejudice in any debate. The best way to try to correct for this is to independently gather information from sources close to the experiments. When the great weight of evidence and opinion from those who perform the tests and gather the data tends in one direction over time it is generally a sign that the conclusion should be taken seriously. And most importantly, in any debate in which self honesty reveals reasons, whether philosophical or economical, etc., that one is guided to a conclusion because of self interest, one should be prepared to acknowledge this.
In the case of climate change I am most impressed with the dramatic increase in the concentration of carbon dioxide (CO2) in the atmosphere over the past half century, as measured from the Mauna Loa station in Hawaii. It is known that CO2 is a strong absorber of infrared radiation that serves as a greenhouse effect and produces terrestrial surface and atmospheric warming. I am personally convinced that human activity is affecting the terrestrial climate in spite of the economic consequences, mostly adverse, that this might mean to me and my family. Such is life.
I do believe that action to counter the human effects of global climate are important. But to me the most important moral of the current debate over climate change is not just the issue itself but the demonstration that prejudice over any issue is damaging to life and to relationships. I have learned to respect people who disagree with me. After all, I am wrong a lot of the time. But, I am concerned about the tendency of society to brand conclusions supported by scientific data as manipulative or faked or part of campaigns to delude the public. That is not what motivates the vast majority of scientists. Whatever one thinks of global climate change, it is more damaging to question the results of data that make one feel uncomfortable.
Impact of the Loss of the Glory Climate Science Satellite
Dr. Bruce Wielicki
About Dr. Wielicki
Dr. Bruce Wielicki is a distinguished Senior Scientist at the NASA Langley Research Center in Virginia. He is an expert on the use of satellites to study the Earth's energy budget, especially the role of clouds and the role clouds play in the Earth's overall climate system. He has been a co-investigator or lead investigator on five NASA space missions in this area, and so is intimately familiar with NASA space missions in general and climate science missions in particular."
Impact of the Loss of the Glory
Climate Science Satellite
The March 4, 2011, launch failure and loss of the Glory satellite is a tragedy for climate science. The Glory satellite included two critical instruments, one to monitor the total energy reaching the Earth from the Sun, and a second to unravel some of the key remaining mysteries about tiny particles called aerosols, especially about the aerosols that humans emit when we burn fossil fuels in cars, power plants, or our homes. Aerosols remain one of the key uncertainties in how fast our fossil fuel burning is pushing the climate system to warmer levels. So, the Glory mission was a key part of understanding how both natural (Sun) and human (aerosols) forcings are acting to change our current and future climate.
If this loss is so serious, why was there no back up strategy? Why was this allowed to be a single point of failure?
The answer is that space missions are expensive by nature, risky by nature, and our nation has decided not to spend the kind of resources it would take for a more robust set of climate research observations. Such an observation system might easily cost 4 to 5 times the current NASA Earth Science budget. Would it be worth it to make more intelligent future decisions about climate change? Without a doubt. But, is there a national will to do it? Evidently not. One way to look at this is that we have a football team with only one player at most positions, and none at a few positions. When one of the players we do have gets hurt, there are no replacements. You play without him and wait until he heals. The time to heal a lost space mission is typically 3 to 7 years depending on budgets and how many spare parts remain from the last instrument builds.
What is NASA's role in climate science?
NASA Earth science missions are a critical part of climate science. Space is the only way to get truly global observations of the Earth and its climate system, from equator to pole, from the U.S. to China. Those observations include everything from the atmosphere to the oceans to the ice sheets to polar sea ice to land cover including vegetation and snow. They include the energy we receive from the sun as well as the solar energy we reflect back to space and the thermal energy we emit to space to shed the solar heat that we absorb. Climate is an interlinked global system including all of these key parts. Looking at just one or even a few of them typically leads to large uncertainties and low scientific confidence.
NASA has led the world in global climate science since the advent of the Earth Observing System that started in 1990, the first attempt at a global Earth observing system. Ironically it was the deficit federal budgets of the mid-1990s that reduced the effort to about 1/3 of its original plan. What we have now are pieces of that system that have lived well beyond their design life. For example, the Aqua spacecraft was launched in 2002, designed for a 5-year mission life, and was originally supposed to have 3 copies launched on 5-year intervals to achieve a continuous climate record over at least 15 years. Only 1 spacecraft was ever built and launched, and has now been operating successfully for about 9 years on orbit. A follow-on mission called NPOESS Preparatory Project (NPP) is finally planned for launch the end of 2011. But, there is no climate observing system in the same sense that there is a weather observing system. NASA is doing the best it can with the limited resources it has. There are no backups.
Should NASA be doing climate science?
The National Aeronautics and Space Act established the agency in 1958. In the Space Act, the first objective of the agency was listed as "the expansion of human knowledge of the Earth and of phenomena in the atmosphere and space." Earth science has been a key part of NASA's mission throughout its history. The need for that mission today is more critical than it was in 1958. When the Space Act was written, we had little idea of potential climate change issues. The Keeling record of carbon dioxide in the atmosphere was just starting in Hawaii. The Keeling record was not the first carbon dioxide observation, but it was the first with the high accuracy over a long time period needed for climate change research.
Many people confuse weather with climate. Why can't weather satellites be used for climate data? In general they lack the high accuracy needed for climate change. Weather accuracy is 1 or 2 degrees in temperature, while climate accuracy is a tenth of a degree, a factor of ten more difficult. In the end, climate observations have requirements that are typically ten times more accurate than weather, and require 10 times as many variables to be observed.
In the U.S. we have a dozen agencies that contribute to climate science and are coordinated using the U.S. Global Change Research Program (USGCRP). NASA resources are the largest contributor to the USGCRP of all the agencies, but none of the agencies has climate as its highest priority. This results in a "curse of the commons" situation where none of the agencies can really lead the development of a climate observing system. Each does the best it can within its limited scope and resources.
They will have a serious impact and will delay advances in understanding carbon dioxide sources and sinks (OCO), natural and man-made aerosols (Glory), and solar climate forcing (Glory). They will also force NASA to evaluate the best balance between use of small less reliable, but less expensive rockets, versus larger more reliable but more expensive rockets. Unfortunately there are no easy answers. It is likely that NASA will continue to find the best option is a range of small to large missions, with a range of small to large costs, and low to high reliability. The resources are not there to design and implement a global climate observing system with a 90% chance of success. Maybe someday that will change.
Dr. Ray Weymann ray.climate (@ sign) charter.net Webmaster Walter Reil walter.climate (@ sign) gmail.com