Population, global projections

They projected life expectancy in the developed countries to reach 81 years by 2050. For less developed countries, this would still reach 76 years. However, this increase in the global elderly population would be proportionally offset by a decrease in fertility rate, now under way, from 1.7 births/woman down to 1.4 in the Western world. This is below the replacement rate. For Second World regions, the rate of about 3.3 births/woman would decline to 1.6. Even in the least developed (Third World) countries, 5 births/woman would fell to 2 by 2050. Thus, the whole world would actually start to depopulate in 40 years. 

Figure 1.2. Historical development of global use of primary energy (in Gtoe) including projected trends to 2100. Insert shows the projected population growth for same period (courtesy of World Energy Council, London, England).

Agriculture consumes by far the most of any use category to which the accessible mnoff worldwide is appHed (Table 6). Postel and co-workers estimate that human uses make up 26% of total terrestrial evapotranspiration and 54% of the mnoff geographically and temporally accessible (9). Increased use of evapotranspiration will confer minimal benefits globally because most of the land suitable for rain-fed agriculture is already in production. New dam constmction could increase accessible mnoff by about 10% over the next 30 years however, population increase during that period is projected to be more than 45%. 

The foremost longer-term global challenge lies in the projection that by 2050 world population will increase from the present 6 billion to close to 10 billion (Census... 

Rice is one of the most important and basic staple foods for about half of the world s population and provides over 20% of the global calorie intake. World rice production is projected to expand by 1.4% per year to 424 million tonnes by 2005, according to the Food and Agricultural Organization (FAO). 

The recent gains in world population and the pressure they place on natural resources is having an impact on the economics of weed control currently and will have far reaching impact on it in the future. Since the early 1940 s the world s population doubled -from less than 2.3 billion to over 4.6 billion in 1983. The annual rate of growth is about 1.7 percent and recent projections indicate the global population will increase to slightly over 6 billion by 2000. 

Vegetational carbon banks would compete with agriculture for land and nutrient resources. It is estimated that a land area about the size of Alaska would need to be planted with fast-growing trees over the next 50 years to use up about half the projected fossil-fuel-induced C02 at a cost of about 250 billion or 50 per person for the global population. One problem is that once the trees are fully grown they no longer take up C02 very rapidly and would need to be cleared so new trees could be planted to continue a quicker uptake. Old trees could be used for lumber, but not fuel, since this would release the C02. If used as fuel, a delay of 50 years, (the typical growth time) would occur and move up the buildup rate of atmospheric C02. 

Program/Global Ecological Fund (UNDP/GEF) report, as of July 30, 1998, showed that the financing of 267 projects by the GEF cost 1.9 billion (GEF, 1998). What was the cost of getting 10,000 people to participate in the Conference in Kyoto The recent Sixth Session of the UNFCCC Conference of the Parties (COP-6, November 13-24, 2000, The Netherlands) as well as the International Conference on Freshwater (December 3-7, 2001, Bonn) were also well populated, with representatives from 178 countries (and then they were mainly officials—not specialists). 

From a different (but related) environmental perspective, provision of adequate supplies of food, shelter, medicines and resources of energy and raw materials already constitute serious global challenges. Superimposed over the issues of safety and the environment introduced above are difficult and long-term problems involving sustainability. The current population of planet earth, approximately 6 billion, has tripled since 1938. Various projections indicate that by 2050 it will be about 11 billion, nearly twice the present level. Innovative methods for greater food production from diminishing tracts of available arable land and increased and efficient utilization of renewable resources will be essential. 

The world population reached 5.8 billion in 1997 and is estimated to reach 8.04 billion by the year 2025. To properly feed and clothe these additional people, food crop yields need to be increased and more natural fibers produced. It is projected that global food demand will double in the next 50 years. Agricultural experts believe that these food and fiber needs can be met, but to do so will require the increased use of pesticides. 

Bipolar disorder (BAD, manic-depressive illness) is a severe and chronic illness, which is a major public health problem, in any given year affecting approximately 1-3% of the US population (Narrow et al., 2002). In the World Health Organization Global Burden of Disease study, BAD ranked sixth among all medical disorders in years of life lost to death or disability worldwide, and is projected to have a greater impact in the future (Murray and Lopez, 1996). 

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