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Ensuring Environmental Sustainability: Some Perspectives Forests cover about 30 per cent of all land but are shrinking - Forests contribute to the livelihoods of many of the 1.2 billion people living in extreme poverty. They nourish the natural systems supporting the agriculture and food supplies on which many more people depend. They account for as much as 90 percent of terrestrial biodiversity. But in most countries they are shrinking. Some loss of forest is an inevitable part of economic development. But because forests are undervalued in many places, they are subject to more destructive and unsustainable activities than is economically or environmentally justified. Protecting land areas to slow the loss of biodiversity - Biological diversity, or biodiversity, refers to the variety of life on Earth, including the variety of plant and animal species, the genetic variability within each species, and the variety of different ecosystems. The Earth's biodiversity is the result of millions of years of evolution of life on this planet. But human activities are causing losses in biodiversity 50 to 100 times faster than would be expected in the absence of human activities. Energy use and a warmer world - The Earth's climate has warmed by about half a degree Celsius this century and much scientific evidence suggests that human activities have contributed to this. The burning of coal, oil, and natural gas and the cutting of forests are changing the atmospheric concentration of green-house gases, changing our planet's climate, with far-reaching consequences. The direction and magnitude of climate change vary across regions, but developing countries are likely to suffer most because of their dependence on climate-sensitive activities such as agriculture and fisheries. They also have limited capability to respond to climate change. By far the most common way to satisfy the need for energy in modern economies is through burning fossil fuels, such as coal, oil, and natural gas, that cause carbon dioxide emissions. Fossil fuel use has increased more than fourfold since 1950. The composition of sources is also changing. In the last 20 years, the use of coal and gas for electricity has increased relative to other sources, while the use of oil has shrunk dramatically. Carbon dioxide emissions mean faster warming - The extensive use of fossil fuels in recent decades has boosted carbon dioxide emissions a major contributor to global warming. Out of estimated 6 to 7 billion tons of carbon dioxide released each year by human activities, some 2 billion tons are absorbed by oceans, and another 1.5 to 2.5 billion by plants, with the rest released in the atmosphere. The level of carbon dioxide in the atmosphere is up by some 30 percent since the beginning of the industrial revolution. According to the Intergovernmental Panel on Climate Change, the rate and duration of warming in the 20th century are unprecedented in the past thousand years the global average surface temperature has increased by about 0.6 degrees Celsius. The warming is expected to continue, with increases projected to be in the range of 1.4 to 5.8 degrees Celsius between 1990 and 2100. Clean water contributes to better health - Lack of clean water and basic sanitation is the main reason diseases transmitted by feces are so common in developing countries. In 1990 diarrhea led to 3 million deaths, 85 percent of them among children. Between 1990 and 2002 about 400 million people obtained access to improved water sources, gains just sufficient to keep pace with population growth. An improved water source is any form of water collection or piping used to make water regularly available. It is not the same as 'safe water,' but there is no practical measure of whether water supplies are safe. Connecting all households to a reliable source of water that is reasonably protected from contamination would be an important step toward improving health and reducing the time spent collecting water. More people have access to safe water compared to 10 years ago. But, in 2002, 1.1 billion people still lacked access to an improved water source, 42 percent of them in Sun-Saharan Africa and 22 percent in East Asia and Pacific. Meeting the Millennium Development Goals will require providing about 1.5 billion people with access to safe water and 2 billion with access to basic sanitation facilities between 2000 and 2015. Water in higher demand - Each year 80 million additional people will tap the earth's water. In the past century, global water withdrawals have increased almost tenfold. Some countries have abundant, untapped stores of water to support growth well into the future. But others are already using most of their water, and major increases in supplies will be expensive. Far from plentiful, rural water has to be shared by the growing cities, the burgeoning rural areas, and a thirsty environment. Needed are greater efficiency in the use of water and fair allocation to balance the limited supply with rising demand. People need safe, reliable supplies of water - In Sub-Saharan Africa 300 million people lack access to improved water sources. South Asia has made excellent progress, but contamination of water sources poses new risks. In East Asia rapid urbanization is posing a challenge for the provision of water and other public utilities. With faster progress here and in other regions, the world as a whole will achieve the target. Data are lacking for Europe and Central Asia in the early 1990s. In the Middle East and North Africa, Egypt, Tunisia, and Morocco have made the fastest progress Slum dwellers exposed to high risks and deprivation |