Forests. Over the past decade, developing countries have been converting or degrading their forests, coastal and inland wetlands, and other ecosystems at historically high rates. Tropical moist forests, for example, are being burned and cut at a rate of 17–20 million hectares per year, or 1 percent a year—if this continues, these forests will disappear within several generations. The loss of forests can pose severe ecological and economic costs (e.g., lost soil and watershed protection, local climate change, and destruction of habitat), not to mention a high human toll (in 1991, 5,000 Philippine villagers were killed by flooding caused in part by deforested hillsides).
Soils. Although less dramatic than images of advancing deserts, the gradual deterioration of agricultural soils, largely through erosion, is a more widespread and serious problem than desertification. Total harvests and yields of important food crops are declining in some countries, particularly in Sub-Saharan Africa, even though yields are increasing globally, as well as in developing countries as a whole. Soil depletion often occurs on fragile lands from which the poorest farmers attempt to wrest a living. Rough estimates suggest that in countries such as Costa Rica, Malawi, Mali, and Mexico, the losses in on-farm productive potential alone may amount to 0.5–1.5 percent of GDP annually.
Which countries account for most global carbondioxide emissions?
Note: From fossil fuels and cement manufacture.
Although official data show significant progress in the 1980s, nearly 1 billion people in the developing world are still without access to clean water for drinking and bathing, and 1.7 billion must contend with inadequate sanitation facilities. Moreover, the quality of service has deteriorated in many areas, and the number of people without access to sanitation continues to increase in urban areas. The result is a host of water-related diseases. Unsafe water is a major contributor to the 900 million cases of diarrheal diseases annually, leading to 3 million deaths, most of them children. At any time, there are 500 million people suffering from trachoma, 200 million from schistosomiasis or bilharzia, and 900 million from hookworm. Cholera, typhoid, and paratyphoid also continue to wreak havoc with human welfare.
Compounding matters in some locations is growing water scarcity, which makes it difficult and expensive to meet increasing demand for drinking water, irrigation, and industrial use. This is a particularly acute problem in arid areas of the Middle East, as well as in places such as Northern China, East Java, and parts of India. Groundwater is being depleted, sometimes irreversibly. Moreover, existing withdrawals from rivers limit further expansion of irrigation and in-stream uses (e.g., river transport, sediment flushing, and fish reproduction).
Consistent monitoring of ambient air pollution is just over a decade old, but it shows that several pollutants—stemming from energy use, vehicular emissions, and industrial production—are frequently over levels considered safe for health.
For the 1.2 billion people living in urban areas in developing Organization standards on dust and smoke, the threat of serious respiratory illnesses looms large. Reducing such pollution, especially in China and India, could save 300,000–700,000 lives every year.
Indoor air pollution from burning wood, charcoal, and dung inside homes—especially in rural Africa and South Asia—endangers the health of 400–700 million people. Women and children suffer most, with some of the same health consequences of those who smoke the equivalent of several packs of cigarettes per day.
High levels of lead, primarily from vehicle emissions contribute to hypertension and high blood pressure and hinder neurological development. Estimates for Bangkok suggest that the average child has lost four or more IQ points by the age of seven because of elevated exposure to lead.
While much environmental damage and loss is evident today, other sources of potential danger—including those that cross national boundaries—may not show their ill effects for decades hence.
Ozone depletion. This is the most immediate “global commons” problem, as scientists continue to record alarmingly high atmospheric levels of ozone-destroying substances—primarily chlorine monoxide, which originates from chlorofluorocarbons. Ozone protects life on earth by absorbing much of the ultraviolet radiation that causes skin cancer, cataracts, and possibly immune-system damage in humans, and reduces the productivity of microscopic marine organisms that are at the base of the oceans’ food chain.
Global warming. Increasing emissions of carbondioxide and other greenhouse gases raise average temperatures on earth, and although the exact size of the effect remains unclear, average world temperatures may rise by 1.5–4.5 degrees Celsius by the second half of the next century. Recent research has reduced fears that ice caps might melt, causing sea levels to rise precipitously, but there are still grounds for concern. Low-lying nations are nonetheless at risk, and agriculture, forests, and ecosystems may not easily adapt to rising temperatures and consequent climate changes. The best estimates, still extremely crude, are that global warming will impose costs 60 years from now equivalent to about 1 percent of world GDP.
Low-income countries are those with a GNP per capita of $610 or less in 1990.
Middle-income countries are those with a GNP per capita of more than $610 but less than $7,620 in 1990.
High-income countries are thuse with a GNP per capita of $7,620 or more in 1990.
Source: All of the charts and data are taken from the World Development Report 1992.