In a pair of recent editorials claiming humans are causing a global warming crisis, Ben Bova of the Naples Daily News disparages mere “assertions” while saying people need to rely on “observable, measurable facts.” While Bova’s concern for the environment is admirable, he should follow his own advice regarding assertions versus facts.
Bova asserts the Earth has a “rising fever.” Yet the fact is that global temperatures are unusually cool. For most of the past 10,000 years temperatures have been 1.0 to 3.0 degrees Celsius warmer than they are today. The 0.6 degree rise in temperatures during the twentieth century occurred from the baseline of the Little Ice Age, which saw the coldest global temperatures during the past 10,000 years. The Earth has a “rising fever” only if we pretend the Little Ice Age was “normal” and ignore the Earth’s long-term temperature facts.
Bova asserts “the loss of sea ice in the Arctic is threatening the survival of polar bears.” Yet the fact is that polar bear numbers have doubled since the 1980s. Moreover, Antarctic sea ice is growing and has been setting records for much of the past year. If “global” warming is causing receding polar ice, then why is Antarctic sea ice setting growth records?
Bova asserts “measurements show that the rise in global temperatures matches quite closely the increase in carbon dioxide.” Yet the fact is that solar scientists at Harvard and other leading universities have published research in the world’s leading scientific journals showing that temperatures match solar output much more closely than carbon dioxide, even in the twentieth century.
Bova asserts that as a result of global warming “much of our crop land turns to desert.” Yet the fact is that global precipitation and global soil moisture have increased during the twentieth century, and the Sahara Desert and other deserts around the world are in retreat.
Bova asserts we run the risk of breaching a “tipping point” or a “greenhouse cliff where the global climate shifts too rapidly for us to protect ourselves from its drastic effects.” Yet the fact is that in a recent survey of more than 500 climate scientists from around the world, less than half agreed that “assuming climate change will occur, it will occur so suddenly that a lack of preparation could result in devastation of some areas of the world.”
Bova asserts that in California’s Yosemite National Park, warmer temperatures are allowing mice and pine trees to live at higher altitudes than a century ago. Yet the fact is that fossilized trees exist at altitudes above the current California tree line, showing that temperatures were significantly warmer 1,000 years ago than today. Plant and animal species are migrating to higher elevations only in comparison to the abnormally cold temperatures of the Little Ice Age that ended just over a century ago. For most of the past 10,000 years, warmer temperatures enabled mice and trees to live at altitudes significantly higher than is possible today.
Global warming activism is long on unsubstantiated assertions and short on objective facts. Only by comparing today’s temperatures to the abnormal cold of the Little Ice Age—and by completely ignoring the warmer temperatures that predominated during most of the past 10,000 years—can global warming activists paint a picture of a planet suffering a global warming crisis.
Moreover, sound science has thrown cold water on each and every one of the alleged global warming crises, such as endangered polar bears, melting ice caps, etc., alleged to result from global warming.
James M. Taylor ([email protected]) is senior fellow of environment policy at The Heartland Institute.