Statistics in the News: Chapter 19 Time Series
From an Unlikely Quarter, Eco-Optimism
The news from environmental organizations is almost always
bleak. The climate is out of whack. Insidious chemicals taint
food and drink. Tropical forests are disappearing. Species
are perishing en masse. Industrial poisons pollute air, land,
and water. Ecosystems are being stressed to the breaking point
by the greedy, wasteful consumption of the Western lifestyle.
The list goes on. Typical examples abound at the site of the
Worldwatch Institute; just visit http://www.worldwatch.org.
So it is a surprise to meet someone who calls himself an
environmentalist but who asserts that things are getting better,
that the rate of human population growth is past its peak,
that agriculture is sustainable and pollution is ebbing, that
forests are not disappearing, that there is no wholesale
destruction of plant and animal species, and that even global
warming is not as serious as commonly portrayed.
The author of this happy thesis is not a steely-eyed economist
at a conservative Washington think tank but a vegetarian,
backpack-toting Danish professor of statistics who
was even a member of Greenpeace not so long ago. Professor
Bjorn Lomborg from the University of Aarhus arrived at this
position by accident, after reading about the famous controversy
(presented in the Preview of Chapter 19) between Paul H. Ehrlich,
the Stanford University ecologist and author of The Population
Bomb, and Julian L. Simon, the University of Maryland
economist and author of The Ultimate Resource. Prof.
Lomborg felt sure that Simon's optimistic contentions were
"simple American right-wing propaganda." So he initiated nightly
study sessions with his statistics students to debunk Simon,
drawing data from reports of the World Bank, the Food and
Agriculture Organization, the United States Environmental
Protection Agency, the International Panel on Climate Change,
and other official sources. Yet Lomborg found that most of
Simon's assertions were correct!
At the same time, Lomborg's work confirms the Chapter 19
warning: "Whenever someone says, 'given present trends…variable
X will do this or that,' you better watch out." Lomborg found
that routine assertions made by environmental organizations,
such as the Worldwatch Institute, the World Wildlife Fund,
and Greenpeace, were exaggerated or outright myths. In his
book, he refers to the persistently gloomy fare from these
sources as the Litany. He chides journalists for uncritically
spreading the Litany and the public for an unfounded
readiness to believe the worst. "The Litany has pervaded the
debate so deeply and so long," writes Lomborg, "that blatantly
false claims can be made again and again, without any references,
and yet still be believed." To understand the world as it
is, he says, it is necessary to look at long-term global trends
that tell more of the whole story than short-term [anecdotes]
and are less easy to manipulate.
His examples include:
1) In its 1998 State of the World report, the Worldwatch
Institute said: "The world's forest estate has declined significantly
in both area and quality in recent decades." But the longest
data series of annual figures (available from the United Nations'
Food and Agriculture Organization) shows that global forest
cover between 1950 and 1994 has in fact increased.
2) The same Worldwatch report claimed that due to soaring
demand for paper, "Canada is losing some 200,000 hectares
of forest a year." Yet the cited reference shows Canada growing
174,600 more hectares of forest a year.
3) In its 2000 report, the Worldwatch Institute cited the
dangers it had foreseen even in 1984: "Record rates of population
growth, soaring oil prices, debilitating levels of international
debt, and extensive damage to forests from the new phenomenon
of acid rain." Yet Lomborg shows that the rate of world population
growth has been dropping sharply since 1964, that the price
of oil--adjusted for inflation--has halved since the early
1980s, that the level of international debt has decreased
slightly between 1984 and 1999, and that sulfur emissions
that generate acid rain have been cut substantially since
1984 (and have done little if any damage to forests, though
some to lakes).
4) According to Ehrlich in 1961, "in the course of the 1970s,
the world will experience starvation of tragic proportions--hundreds
of millions of people will starve to death." Yet Lomborg finds
world population doubled since 1961, while calorie intake
has increased by 24 percent as a whole and by 38 percent in
5) Lomborg also takes issue with global warming predictions.
Four reasons are usually cited as to how waste gases could
warm the world's climate. These include the multiplier effect
of carbon dioxide, the role of clouds, the effect of aerosols,
and the sunspot cycle. According to the multiplier effect,
as carbon dioxide heats the atmosphere a little, the air can
hold more water, and that heats the atmosphere a lot more.
Yet Lomborg's satellite and weather balloon data weaken the
case for such a multiplier effect. And he argues that the
climate model employed by the International Panel on Climate
Change exaggerates the effects of greenhouse gases.
6) Lomborg portrays several other elements of the Litany
as little more than myths. These include the claim that the
world is about to lose half or more of its species. (The often
quoted figure that 40,000 species are lost every year comes
from a 1979 article by Norman Myers, an Oxford University
ecologist who, without any evidence, simply speculated
that 1 million species might be lost between 1975 and 2000,
which comes to 40,000 a year.) Yet the International Union
for the Conservation of Nature, which maintains the Red Book
of endangered species, in fact concluded in 1992 that extinction
figures for mammals and birds were "very small" and that the
total extinction rate, out of 30 million species, was probably
2,300 a year. A far cry from what Myers, even in 1999, called
"a human-caused biotic holocaust."
Sources: Adapted from John Tierney, "Betting the Planet,"
The New York Times Magazine, December 2, 1990, pp.
52-81, and Nicholas Wade, "From an Unlikely Quarter, Eco-Optimism,"
The New York Times, August 7, 2001, pp. D1 and 2.
Lomborg, Bjorn. The Skeptical Environmentalist (Cambridge
University Press, 2002).
A substantial work of statistical analysis,
with almost 3,000 footnotes, that criticizes false statements
routinely made by environmental organizations, such as the
Worldwatch Institute, the World Wildlife Fund, and Greenpeace,
that are typically based on questionable "trends."