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Sharing the Adventure with the Public: The Value and Excitement of 'Grand Questions' of Space Science and Exploration: Summary of a Workshop (2011)

Chapter: Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?

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Suggested Citation:"Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?." National Research Council. 2011. Sharing the Adventure with the Public: The Value and Excitement of 'Grand Questions' of Space Science and Exploration: Summary of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/13276.
×

Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?

Moderator:

Molly Macauley, Resources for the Future; Space Studies Board (SSB) Member

Speakers:

Berrien Moore III, University of Oklahoma; SSB Member; Former Co-Chair of the National Research Council Committee on Earth Science and Applications from Space: A Community Assessment and Strategy for the Future

Roger-Maurice Bonnet, International Space Science Institute, Switzerland

Panelists:

Andrew Lawler, Science Journalist

Christie Nicholson, Journalist and Online Contributor, Scientific American

INTRODUCTION

Molly Macauley, a senior fellow at Resources for the Future and a member of the SSB, used her introduction to set the context for the speakers. She outlined three points: “the policy relevance [of Earth science research from space], … what’s different about humanity’s relationship to Earth now and moving forward with the vantage point of space and aerospace technology, [and] that some fundamental issues still remain, most notably the national sovereignty of resources, and how, taken together, those interfere with or facilitate the management of global resources.”

Macauley first noted that one can learn from the past and cited two books that provide historic retrospectives.1 She said the theme of the first book is that humankind tends to be myopic about decisions on natural resources, especially in the face of short-term hardship. The theme of the second book is quite different, however. It focuses on what gives rise to technological change that enables us to augment resource scarcity and better foster and manage the “spirit of inquiry.” The authors were not thinking about space when the books were written, she said.

With regard to the policy relevance of Earth science research from space, Macauley spoke about how a handful of nations around the world are using data from space to make policy decisions with economic consequences—“a direct economic link to how we do business and how we manage our climate.” Regarding what has changed, she quoted a 2007 National Research Council (NRC) report that articulates the impact of the ability to see Earth from space and using spacecraft to study our planet: “Just as the invention of the mirror allowed humans to see their own image with clarity for the first time, we can now see ourselves for the first time living on and altering a dynamic planet. We have barely seen the beginnings.”2

As for challenges such as the national sovereignty of resources, she explained that there are still discrepancies in the fundamental measure of acreage of forests around the world, despite the global Earth observation capacity because “not all countries choose to make known very good measures of forests.” She said that some people argue that “we have better maps of Mars and the Moon than we do global forest areas.”

________________

1 J. Diamond, Collapse: How Societies Choose to Fail or Succeed, Penguin Group, New York, 2005; J. Mokyr, The Lever of Riches: Technological Creativity and Economic Progress, Oxford University Press, New York, 1992.

2 National Research Council, Earth Observations from Space: The First 50 Years of Scientific Achievements, The National Academies Press, Washington, D.C., 2008, p. 1.

Suggested Citation:"Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?." National Research Council. 2011. Sharing the Adventure with the Public: The Value and Excitement of 'Grand Questions' of Space Science and Exploration: Summary of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/13276.
×

image

FIGURE 10 History of changes in the atmospheric concentration of carbon dioxide taken for direct measurements made in Mauna Loa, Hawaii since 1958. SOURCE: Created with National Oceanic and Atmospheric Administration published data for Global Warming Art by Robert A. Rohde.

BERRIEN MOORE III

Berrien Moore III, dean of the College of Atmospheric and Geographic Sciences at the University of Oklahoma and the former co-chair of the National Research Council’s decadal survey on Earth science and applications from space and an SSB member, began by commenting that he does not feel part of the “tweet generation” because he and other climate scientists have gotten “hate tweets” ever since Climategate. 3

Moore went on to discuss global climate change and the measurements of carbon dioxide (CO2) at Mauna Loa, Hawaii, since 1957 (Figure 10) that show the concentration of CO2 in the atmosphere is rising.

Comparing it to the monetary system, he said we are taking carbon out of “central banks” (oil wells and coal mines) and inflating the carbon cycle. Even if CO2 was not a greenhouse gas, the “human perturbation at the global scale is … quite a remarkable change.” Between 2000 and 2008, there was a huge increase in CO2 emissions, but it diminished with the global economic downturn and now is starting to come back. About half—45 percent—of CO2 stays in the atmosphere in any year, and about half of the other half (25 percent) is removed by the oceans. The remaining half of the half (25 percent) is removed by the terrestrial landscape, so land-based CO2 is increasing. More carbon is being stored every year in vegetation, which means the biosphere is increasing. There are two reasons for that: a fertilization effect by making plants more water efficient and land use recovery where forests have been cut.

________________

3 “Climategate” is explained by Dr. Charles Kennel in Session 1.

Suggested Citation:"Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?." National Research Council. 2011. Sharing the Adventure with the Public: The Value and Excitement of 'Grand Questions' of Space Science and Exploration: Summary of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/13276.
×

So what does it take to stabilize CO2 in the atmosphere?, Moore asked. “If you stabilize emissions, the atmospheric concentration goes up linearly,” so we have to “reduce fossil fuel consumption by about 80 percent.”

He then embarked on a discussion of what we know, what we think we know, and what we don’t know about climate change.

What We Know

Moore said that what we know for certain is that CO2 is a greenhouse gas, the atmospheric concentration of CO2 is increasing, fossil-fuel burning is the primary cause of the increase, fossil fuels are at the center of most economies as a consequence of the industrial revolution, CO2 is a long-lived gas in the atmosphere (500 or more years) and stabilizing it will be difficult.

The Intergovernmental Panel on Climate Change (IPCC) studied these issues for many years. Its third and fourth reports, in 2001 and 2007 respectively, led to a warning in 2007 that “warming of the climate system is unequivocal.” The 2001 report said that the warming “likely” was due to human causes, a word that, he explained, in IPCC terms means “two out of three.” The 2007 report, by contrast, said it was “very likely,” which Moore said meant “nine out of ten.” Space-based observations contributed significantly to the IPCC’s work, and he reviewed a number of spacecraft missions whose observations contribute to the understanding of climate change. He cited the Gravity Recovery and Climate Experiment (GRACE) mission for its ability to study changes in ice mass in Greenland, and Europe’s ENVISAT radar satellite for finding the Northwest Passage, in particular. (See Figures 11 and 12.)

Quoting from the 2007 IPCC report, Moore said the “Faustian bargain” is that “anthropogenic warming and sea level rise would continue for centuries due to the timescales associated with climate processes and feedbacks, even if greenhouse gas concentrations were to be stabilised.”4

What We Think We Know

Therefore, what we think we know, Moore said, is that the planet is warming in response to the increase in the atmospheric concentration of CO2 and other greenhouse gases, the increase in global temperatures will alter rainfall patterns, the climate will continue to change even when CO2 is stabilized, and climate change itself will likely change the atmospheric concentration of CO2, and carbon cycle sinks may weaken. That could make it even more difficult to stabilize atmospheric concentrations, so the cuts may have to be more than 80 percent. None of the climate models capture the arctic sea ice decline, he added. Also, some models perform better than others in “capturing the 20th century climate.” Their relative ranking “varies considerably from one variable to the next.” The one exception is the “mean model” that “consistently outperforms all the others,” and it bothers him as to why that would be true.

Moore’s bottom line is that “The understanding of the climate system is inadequate to adequately foresee our future. We are not in a good situation.”

Thus, the scientific community has agreed on 44 essential climate variables that “should form the litmus test for all climate modeling.”

________________

4 Intergovernmental Panel on Climate Change, Summary for Policymakers in Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (S. Solomon, D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller, eds.), Cambridge University Press, Cambridge, United Kingdom and New York, N.Y., p. 16.

Suggested Citation:"Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?." National Research Council. 2011. Sharing the Adventure with the Public: The Value and Excitement of 'Grand Questions' of Space Science and Exploration: Summary of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/13276.
×

image

FIGURE 11 Changes in Greenland as seen by Gravity Recovery and Climate Experiment. SOURCE: Courtesy of Russell Huff and Konrad Steffen, University of Colorado Cooperative Institute for Research in Environmental Sciences.

image

FIGURE 12 Envisat, a “new” northwest passage, September 2007. SOURCE: Courtesy of the European Space Agency.

Suggested Citation:"Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?." National Research Council. 2011. Sharing the Adventure with the Public: The Value and Excitement of 'Grand Questions' of Space Science and Exploration: Summary of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/13276.
×

What We Don’t Know

What we do not know, Moore continued, is how to “swap out” the energy system of Earth for one that is “nearly carbon neutral without wreaking economic havoc.” He proceeded to illustrate the magnitude of the problem by showing how many wind farms or nuclear power plants would be needed to reduce fossil fuel emissions by 80 percent. He said that the largest wind farm in the world is the Lynn and Inner Dowsing Wind Farm off the east coast of England. Using that as a unit, there are 850 Lynn and Inner Dowsing Wind Farm equivalents in the world today producing approximately 2 percent of the world’s electricity supply. To meet the total world electricity demand, at least 42,500 would be required, but electricity demand is rising 2 percent per year. Thus, one would need 850 of these wind farm equivalents every year just to stay even, not to swap anything out. The world’s largest nuclear power plant produces the equivalent electricity of 42 of the largest wind farms, so 20 of the largest nuclear power plants would have to be built every year to stay even.

Moore ended by observing that “What we really don’t know how to do … is communicate this to the body politic. We have failed miserably.” “We thought we were succeeding, but it appears our communication was very, very fragile and that as soon as the Climategate and the tweets started happening support for this [conclusion] that we have a real problem seemed to evaporate.”

ROGER-MAURICE BONNET

Roger-Maurice Bonnet, executive director of the International Space Science Institute, who spoke in Session 1, returned to the stage as the second speaker in this session. This time his topic was whether and how humanity can survive the next 1,000 centuries, the topic of a book he co-authored with Lodewijk Woltjer.5

Bonnet compared Earth to the International Space Station (ISS). Both have power supplies, communications, multilayer insulation, and life support systems, for example. The ISS has renewable, efficient solar energy for power, and with six crew members it is “nearly full,” he said. “Spaceship Earth also is nearly full,” with 6.5 billion people. Based on United Nations data, however, Earth’s population growth is slowing down, which is good. However, “Spaceship Earth” is warming—its thermal stabilization system is not working.

What is really of concern is how rapidly it is warming, which creates social problems. The Department of Defense has undertaken a study about the consequences of warming on global stability.

Bonnet provided an example of the effect of global warming on streamflow and how by 2060 it might be enough to change the course of rivers with consequent effects on food availability (Figure 13).

He said that there will be an end to the availability of oil at some point, and we will be “forced” to use other forms of energy. Nuclear fusion and solar energy could be part of the solution to energy needs. He does not think there is a problem with the availability of water, rather, it is a problem of piping and purification. To sustain the projected population of 11 billion (the estimate used in his book), 11,000 cubic kilometers of usable water are needed, and there are 16,000 cubic kilometers available if one includes the oceans; desalinization therefore is a requirement.

A bigger problem, Bonnet said, is “vanishing minerals,” including gold, silver, antimony, and indium, all of which will be in short supply by 2050. Indium availability is particularly critical because it is used in semiconductors, photovoltaic cells, and liquid crystals, but a recent study says reserves will be exhausted in 15 years. Indium and antimony, in particular, need to be recycled, he asserted. They can be found in dumps, but no one is doing it. Phosphates also are critical for agriculture, but there are reserves only for the next 125 years. Phosphates should be recycled from livestock waste, Bonnet said.

________________

5 L. Woltjer and R.-M. Bonnet, Surviving 1,000 Centuries: Can We Do It? Springer-Praxis Publishing Ltd., Berlin, Germany, 2008.

Suggested Citation:"Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?." National Research Council. 2011. Sharing the Adventure with the Public: The Value and Excitement of 'Grand Questions' of Space Science and Exploration: Summary of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/13276.
×

image

FIGURE 13 Effect of global warming on streamflow. SOURCE: M. Moyer, How much is left? Scientific American 303:74-81, 2010, doi:10.1038/scientificamerican0910-74. Courtesy of Jessica Huppi, Scientific American (from “Global Pattern of Trends in Streamflow and Water Availability in a Changing Climate,” by P.C.D. Milly et al., in Nature, Vol. 438; November 17, 2005).

Eschewing the idea that the population can be saved by moving into space colonies as envisioned years ago by Gerard O’Neill, Bonnet said that all we have is Earth and maybe the Moon.

So “we have a problem, and we have to solve it.” Returning to the ISS analogy, he said there is no growth for the crew beyond the livable limits of growth; a 10-person space station cannot support 15 people. Water management rules are essential, resource management through recycling is mandatory, alimentation and resource management and new practices are necessary, and maintenance and repairs require that a high level of engineering capability be kept on board.

What is true for the ISS is also true for Earth, he said, and illustrated a number of other problems facing Earth in addition to climate change. Referring to the 1971 Apollo 13 lunar mission that nearly ended in tragedy and the crew’s urgent call “Houston, we have a problem,” Bonnet asked, “Where is Houston for ‘Space Station’ Earth?”

Probably not in Houston, he answered, but maybe in New York City at the United Nations. The people of Earth, through education and engineering and research capability, he asserted, are the only ones who can help repair Space Station Earth.

To manage Earth for the next 1,000 centuries, the topic of his book, he listed five needed actions, saying that some are from the policy announced by President Obama several months ago:

• Strengthen human capital;

• Improve civilian protection in risky areas;

• Reinforce education;

• Sustain science, technology and innovation; and

• Ensure the availability of a comprehensive space system.

Suggested Citation:"Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?." National Research Council. 2011. Sharing the Adventure with the Public: The Value and Excitement of 'Grand Questions' of Space Science and Exploration: Summary of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/13276.
×

On the last point, he emphasized the “critical role” that space plays. Spacecraft are needed to monitor Earth, referring to the GRACE mission in particular, which was cited by Moore in the previous talk. GRACE measures the shape of Earth and allows scientists to see where the water is and how Earth is deforming. The atmosphere—which Bonnet likened to multilayer insulation on the ISS—can be measured from space. Space also is needed for studying ocean temperature; forecasting the weather; monitoring water, fires, anthropogenic environmental deterioration, volcanoes, and the Sun; observing the universe; and exploring new worlds.

Earth needs “new global management” like the ISS, for which 6 countries have provided hardware and to which 16 nations have sent astronauts. There is a code of conduct for astronauts on the ISS, and there should be a comparable one for Earth. Bonnet then listed what he sees as a needed set of “new universal rights to solar energy, fresh water, food, education, and scientific research.”

As for whether humanity can survive 1,000 centuries, he showed a slide of President Obama saying “Yes we can.”

PANEL DISCUSSION

Christie Nicholson, journalist and online contributor for Scientific American, and science journalist Andrew Lawler joined Macauley, Moore, and Bonnet on the panel.

In response to a question from Macauley about how the climate science community should tell its stories, Nicholson said that she does not think the public considers NASA or the space program as the source of information about climate change. She thinks the public would be quite surprised to learn how much climate information comes from NASA missions. In response to Moore’s conclusion that climate scientists had failed to communicate the seriousness of the problem to the public, she asked how that could be true because people think about Earth “all the time now.” It is embedded in their minds. She added that it is important to look at the social psychology of why people believe in climate change or not. There are strong confirmation biases, depending on how an individual looks at Earth. “Those that think Earth is robust tend to be entrepreneurs; those that think Earth … is fragile tend to be more of the radicals in the environmental movement,” she said. These beliefs are strong, and people are not conscious of them, and it leads to strong confirmation biases.

Lawler said that he was struck at how stark a situation Moore painted. He liked the way it was presented—what we know, what we think we know, and what we don’t know—but it lacked a narrative. It is “doom and gloom” to which people do not respond well. He said Bonnet’s approach of storytelling is better.

Moore replied that he had not cast his talk as though it was for the general public. Overall, he thinks something else is at work “in terms of worldview or how scientists are viewed.” He observed that although people frame the question, Do you believe in climate change?, it is not a belief based topic. The data are there, he said.

Lawler disagreed. It is about belief, he insisted, and that although he had learned to trust and believe the data Moore presented, there has been a loss of trust, and he sees this in journalism, too—people do not know who to believe. He acknowledged that scientists have a difficult time understanding that some people do not believe the data charts. Nicholson concurred, adding that even two scientists can draw different conclusions from the same data. It is a confirmation bias—some people will believe one scientist versus another, she said: “I don’t know when climate change … became such a strong belief system on the level of religion and political beliefs, but it has.”

Later Nicholson added that humans have never been skilled at worrying about the long-term future, and perhaps the messaging needs to change to “how do we adapt to a warmer climate,” which is more positive.

As the conversation continued during the audience participation segment, Moore appeared to have an epiphany, saying to Lawler that he believed that he had been missing the whole point—that it is not whether people believe or not in global warming, it is whether they believe or not “in what we said.”

Suggested Citation:"Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?." National Research Council. 2011. Sharing the Adventure with the Public: The Value and Excitement of 'Grand Questions' of Space Science and Exploration: Summary of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/13276.
×

There has been a reinforcement of doubt about what climate scientists are saying. At the end of the session he thanked Lawler and Nicholson “because I learned something.”

AUDIENCE INTERACTION

An audience member said that a common reaction to a catastrophe is to send money not to change habits. Lawler said that the resilience of society is a theme of studies of collapsing societies—there are very few such collapses, instead the society changes. Despite the Black Death in Europe, when one in four people died, society continued, he said.

The influence of those with vested interests in current forms of energy was raised by another audience member. Coal-fired power plants are the cheapest form of energy, and people are accustomed to today’s energy costs and “want the dream to keep going on,” he said. Thus, they are open to messages from those with vested interests who may not directly dispute climate change science, but raise doubt about it. How do you put a dollar cost on not doing anything in order to “scare people,” to make them understand that the quality of their lifestyles will go down if nothing is done, he asked. Moore and Macauley agreed that it is difficult to calculate, much less communicate, the economic costs of inaction, even though, as Moore said, “The cost of doing nothing costs something.”

Kennel said that his institute (the Scripps Institution of Oceanography at University of California, San Diego) has concluded that climate scientists need to “enrich the narrative” by talking about adaptation, as Nicholson suggested. That would change the principal tool—the IPCC—that has been used to date to attribute the cause of climate change and that it is human induced. The IPCC speaks to 15,000 to 20,000 decision-makers in government and industry, but ordinary people need to understand it on a local level. The “cost of inaction” can be understood better on that level, but it means that building trust must be done differently. “I don’t think we know how to do that,” he said, and it will require a deep alliance between scientists and communicators.

Lawler insisted that the science community has to make a decision on what it will do. Climate change “is a fascinating … story of how a group of people who see the train wreck that’s happening is going to respond” to the “huge political struggle, huge economic forces aligned with keeping inertia [and] preventing change.” Will scientists quietly work to amass more data or “go to the barricades” and find a wealthy backer to set up a website and “tweet” to get the message out? He advised scientists to think carefully about how they want to convey this topic to journalists.

Nicholson offered that it is important to decide how to frame the issue and gave examples from health communications, where different messages can be framed as a gain or a loss. The message is communicated quite differently if the goal is to get people to use sunscreen versus getting a mammogram. Wearing sunscreen is a preventive measure that is low risk—it protects a person from the Sun, she explained. In that case, the message is that it is a benefit, a gain. But a mammogram is high risk psychologically because it might reveal a tumor, so the message must be framed as a serious loss—that if one does not have a mammogram it could be fatal.

Suggested Citation:"Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?." National Research Council. 2011. Sharing the Adventure with the Public: The Value and Excitement of 'Grand Questions' of Space Science and Exploration: Summary of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/13276.
×
Page 35
Suggested Citation:"Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?." National Research Council. 2011. Sharing the Adventure with the Public: The Value and Excitement of 'Grand Questions' of Space Science and Exploration: Summary of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/13276.
×
Page 36
Suggested Citation:"Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?." National Research Council. 2011. Sharing the Adventure with the Public: The Value and Excitement of 'Grand Questions' of Space Science and Exploration: Summary of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/13276.
×
Page 37
Suggested Citation:"Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?." National Research Council. 2011. Sharing the Adventure with the Public: The Value and Excitement of 'Grand Questions' of Space Science and Exploration: Summary of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/13276.
×
Page 38
Suggested Citation:"Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?." National Research Council. 2011. Sharing the Adventure with the Public: The Value and Excitement of 'Grand Questions' of Space Science and Exploration: Summary of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/13276.
×
Page 39
Suggested Citation:"Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?." National Research Council. 2011. Sharing the Adventure with the Public: The Value and Excitement of 'Grand Questions' of Space Science and Exploration: Summary of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/13276.
×
Page 40
Suggested Citation:"Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?." National Research Council. 2011. Sharing the Adventure with the Public: The Value and Excitement of 'Grand Questions' of Space Science and Exploration: Summary of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/13276.
×
Page 41
Suggested Citation:"Session 5: The Earth: Will It Remain a Hospitable Home for Humanity in the Future?." National Research Council. 2011. Sharing the Adventure with the Public: The Value and Excitement of 'Grand Questions' of Space Science and Exploration: Summary of a Workshop. Washington, DC: The National Academies Press. doi: 10.17226/13276.
×
Page 42
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On November 8-10, 2010, the National Research Council's Space Studies Board (SSB) held a public workshop on how NASA and its associated science and exploration communities communicate with the public about major NASA activities and programs. The concept and planning of the workshop developed over a period of two years. In conjunction with the SSB, the workshop planning committee identified five "Grand Questions" in space science and exploration around which the event was organized. As outlined in the summary, the workshop concluded with sessions on communicating space research and exploration to the public.

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