Time to change, or find another planet


First of two parts Next week, tens of thousands of politicians, bureaucrats, activists and policy analysts will descend on Johannesburg, South Africa, for the largest conference in human history: the World Summit on Sustainable Development.

Their collective goal at this gathering, also known as the Second Earth Summit, is to adopt a plan of action aimed at conserving the planet and helping the less fortunate. If they are truly courageous, they will also state with urgency that — at the rate humans are consuming natural resources — we will soon need an extra planet or two to satisfy all of our desires.

This concern, that global resources are being depleted at an unsustainable rate, is not new. Scientists have warned for decades that we are exploiting resources at levels beyond the Earth’s capacity to reproduce them. In fact, delegates at the first Earth Summit, in Rio de Janeiro in 1992, voiced their commitment to pursuing worldwide sustainable development. Today we are 10 years older and, though not much wiser, far better informed.

The most recent research warning us of our environmental profligacy is the “Living Planet Report 2002,” published in June by the World Wide Fund For Nature based in Gland, Switzerland (which is known in the United States and Canada as the World Wildlife Fund). According to the WWF, although sustainable ecosystems are vital to human survival, the global community has yet to get serious about this. As Claude Martin, director general of WWF International, points out in the report: “The term ‘sustainable development’ has entered into everyday language [since the Rio Summit], and yet it remains an elusive concept. Indeed, it is now used by governments, industry and nongovernmental organizations to mean almost anything they want it to mean.”

If we do decide to get serious, however, the concept is quite simple. The WWF, the UN Environment Program and the IUCN (The World Conservation Union) have agreed on a definition of sustainable development as: “Improving the quality of human life while living within the carrying capacity of supporting ecosystems.”

Easier said than done, of course. Martin notes that since Rio we have made improvements “in the quality of life for people in many parts of the world” — though he warns that biological overdrafts remain a serious problem. In his words, the crux of the matter is: “We live on a bountiful planet, but not a limitless one. The Earth has a limited capacity to yield its renewable resources.”

The good news, according to him, is that a sustainable society is achievable. “Provided that [the planet’s] capacity is not diminished, the Earth will continue to provide food, materials, energy and fresh water each year, in perpetuity.” But, he notes: “Ensuring access to basic resources and improving the health and livelihoods of the world’s poorest people cannot be tackled separately from maintaining the integrity of natural ecosystems.”

WWF’s “Living Planet Report 2002” takes a close look at the condition of these ecosystems and the human impacts on them. It is, in short, a check-up on the health of the Earth. In order to illustrate our uses and abuses of the natural environment, the report enlists two measurements: the Living Planet Index and the Ecological Footprint.

The LPI offers a look at the condition of ecosystems based on the abundance of species they support. It is calculated as the average of three ecosystem-based indices: a forest-species population index; one for marine species; and one for freshwater species. Each index measures species population trends in a specific type of ecosystem. The EF, in contrast, is computed to show human consumption of renewable natural resources — by country, region and worldwide — in relation to the Earth’s capacity to regenerate these resources.

The LPI indices reveal a worrisome trend over the past three decades. The forest-species index shows that, of 282 species of birds, mammals, and reptiles inhabiting forest ecosystems worldwide, populations have declined by an average of 15 percent. The freshwater index of 195 species living in lakes, rivers and wetland ecosystems shows an average decline of 54 percent. The marine species index, too, shows an average drop of 35 percent in the populations of 217 species inhabiting coastal and marine ecosystems.

Overall, the LPI finds an average decline of 37 percent between 1970 and 2000. Population changes, though, are not uniform. According to the report: “Tropical and southern temperate regions are losing biodiversity the fastest, whereas northern temperate regions appear to be more stable, or in slower decline since 1970.” But as the authors note, this does not necessarily mean northern ecosystems are in a better shape, only that, by comparison, they have changed little over the past 30 years.

Complementing the LPI, the EF compares our consumption of renewable resources with nature’s capacity to reproduce these resources. A nation’s footprint is “the total area required to produce the food and fibres that country consumes, to sustain its energy consumption, and to give space for its infrastructure.” Since we consume resources from all over the globe, our “footprint” is the sum of all we consume, wherever it may come from.

So how big is our human footprint? Only about a quarter of the Earth’s surface is highly productive biologically, according to the WWF. This means the bulk of biomass production takes place on about 11.4 billion hectares, which means the globe’s 6 billion people each has an average of 1.9 “global hectares” (the WWF defines a global hectare as 1 hectare of average biological productivity).

However, humanity’s global ecological footprint in 1999 covered 13.7 billion hectares — or 2.3 global hectares per person. This means that three years ago, human consumption of natural resources “overshot the Earth ‘s biological capacity by about 20 percent,” according to the WWF.

The report notes that we have been running up an ecological deficit with the planet since the 1980s, and between 1961 and 1999, humanity’s ecological footprint grew at an average annual rate of 1.6 percent. World population, meanwhile, grew 1.8 percent per year. Given the numbers and the trends, even my 8-year-old understands something has got to give.

Not surprisingly, North Americans have the largest footprints, while Asians and Africans have the smallest. Per capita, high-income nations have footprints that are, on average, six times the size of low-income nations’ — and more than three times the Earth’s capacity to reproduce resources. Of the nations the WWF lists, 64 have consumption at or exceeding 1.9 global hectares per person, while eight are below the 1.9-hectare breakeven mark. Ecuador and China are the two on the list that consume the least per capita, while the United Arab Emirates and the United States consume approximately 10 global hectares of resources per person.

Politicians, of course, insist that a growing economy is our one overriding concern. But as Martin gently warns: “Unless we recognize the ecological limits of the biosphere, we cannot claim to be sustainable.”

Put more bluntly: unsustainable societies are doomed, Wall Street notwithstanding.