Last week, the Congressional Black Caucus released a report that concluded that blacks are disproportionately affected by climate change.
According to the report, blacks are more likely to live in polluted areas, to lose their jobs, or even to die in heat waves because of climate change. All this suffering, even though “both historically and at present, African Americans emit less greenhouse gas” than other Americans, according to the report.
Thus we see a marriage of two great themes of modern American public life: identity politics and environmental hand-wringing. Even if a problem affects the entire planet, some group will find a way to don the mantle of victimhood. In this case, the apparent oppressors are the industries and individuals responsible for putting greenhouse gases into the atmosphere.
The caucus report is based on mountains of evidence collected from recent decades of research from climatologists around the world. There is overwhelming consensus in the scientific community that global warming is real, and that human activity is to blame.
This scientific consensus is used by supporters of the Kyoto Protocol to argue that America and other industrialized nations should bear the economic burden of drastically reducing greenhouse gas emissions, while the increasing emissions from developing countries like Mexico and communist China remain unchecked.
The problem is, the consensus viewpoint still has gaping holes in it. Global-warming skeptics and energy-industry lobbyists have been pointing out flaws in the science of climate change for years. But even setting aside those critical objections, the fact remains that we know astonishingly little about our planet’s dynamic and complex climate system.
Our ignorance was driven home last week with the news that the sun may have more to do with the global warming trend than researchers anticipated. A team of scientists, led by the managing director of the Max Planck Institute for Solar System Research in Germany, Sami Solanki, analyzed sunspot activity over the last 1,150 years.
By measuring the concentration of a beryllium isotope in ice cores from Greenland and Antarctica, the researchers were able to construct a record of the sun’s past activity—and they double-checked their work against the records of the last few centuries of written sunspot observations.
Dr. Solanki and his colleagues found that the “sun was never as active as during the last 60 years.” They further found a “reasonable correspondence” between the increased solar activity and the global warming of the last half-century.
This new finding does not refute the connection between greenhouse gases and global warming. In fact, the researchers explicitly point out that our planet’s average temperature continued to rise in the last two decades even though sunspot activity “has remained basically constant” during that time. At the very least, though, the evidence shows that climate researchers should dedicate more attention to investigating non-human factors that might contribute to climate change.
Of course, the notion of a connection between solar activity and changes in terrestrial temperatures is far from novel; scientists have long suggested connections between sunspots and abnormal weather patterns.
We know very little about the nature of that connection—how, why, or when the sun will affect Earth’s climate—although we do know that there have been many major shifts in the planet’s climate system, including glacial changes that have unfolded over eons and other severe weather fluctuations that lasted just a few years at a time.
But we are only beginning to grasp the complexities of our planet’s climate, and the interaction of atmospheric composition, cycles in solar activity, irregularities in Earth’s tilt, and countless other ever-changing contributing factors.
You might think that many on the left would be humbled by the extent of our remaining ignorance. You might think environmentalists would remember the wrongness of their fearful predictions in previous generations—like the neo-Malthusian warnings of a “population explosion” in the 1960s or the “global cooling” scare in the 1970s.And yet liberals continue with facile confidence to remark on man’s culpability for global warming, and to call for drastic measures to remedy the problem.
For policy-makers, there is a large lesson to be had here—a lesson about scientific consensus and ignorance. The triumph of modern science is made possible by a constant churn of self-correction. Scientists do their best to offer provisional answers to partial questions; incomplete knowledge is the rule, not the exception.
Policy-makers—especially those who would have us ratify the Kyoto Protocol or go to other great lengths to curb greenhouse gas emissions—would be well served to remember the nature of the scientific enterprise, for it can be dangerous to build long-term policies solely on the shifting sands of scientific consensus.
– Mr. Keiper is managing editor of The New Atlantis.