While there has been a steady increase of population growth during the past two or three centuries, it has been especially rapid during the past 20 years. To appreciate the pace of population growth we should recall that world population doubled in about 1, years from the time of Christ until the middle of the 17th century; it doubled again in about years, doubled again in less thanand, if the current rate of population increase were to remain constant, would double every 35 years. Moreover, this rate is still increasing. To be sure, the rate of increase cannot continue to grow much further.
Carbon dioxide emissions have grown dramatically in the past century because of human activity, chiefly the use of fossil fuels such as oil and coal, as well as changes in land use such as cutting down forests. These emissions are a key contributor to climate change that is expected to produce rising temperatures, lead to more extreme weather patterns, facilitate the spread of infectious diseases, and put more stress on the environment.
The United States is the largest contributor of total carbon dioxide emissions, and has one of the highest per capita rates.
Per capita use also has gone up in China, rising from 2. China is expected to surpass the United States in total carbon dioxide emissions by The vast majority of energy comes from the burning of fossil fuels oil, natural gas, and coal.
The increased use of fossil fuels has a negative effect on the health of the environment in terms of air and water pollution. Air pollution from greater coal use and vehicle exhaust has led to acid rain, which is particularly damaging to forests, lakes, and streams.
Rising fossil fuel use also means a greater build-up of carbon dioxide in the atmosphere, higher greenhouse gas emissions, and global warming. The environmental costs of using fossil fuels have led to efforts to decrease their level of use.
Alternative energy sources that are more efficient are being sought, such as renewable resources like hydropower and solar power. Reducing the environmental costs from energy consumption and ensuring there will be an adequate supply of energy for the future involves the careful management of existing and potential resources.
The loss of trees due to overcutting of forests. One consequence of deforestation is soil erosion, which results in the loss of protective soil cover and the water-holding capacity of the soil.
The process of grasslands being converted to desert mainly as a result of deforestation, overgrazing, and erosion due to poor land management.
A situation that exists when people lack secure access to sufficient amounts of safe and nutritious food for normal growth and development and an active and healthy life. Food insecurity may be chronic, seasonal, or transitory. A group of primary energy sources created from the incomplete biological decomposition of dead organic matter.
The fossil fuels include oil, coal, and natural gas and account for about 90 percent of all the energy consumed in the world. The practice of supplying land with water artificially by means of ditches, pipes, or streams.
Less developed countries include all countries in Africa, Asia excluding Japanand Latin America and the Caribbean, and the regions of Melanesia, Micronesia, and Polynesia. The surface water runoff from local precipitation, the inflow from other regions, and the groundwater recharge that replenishes aquifers.
Farming at a level at which only enough food is produced to meet immediate local needs. Discussion questions What were the levels of birth and death rates in less developed countries and in more developed countries in ?
Describe how the birth and death rates in the less developed and more developed countries changed from to Reading What are the components of population change? How does the world population growth rate today compare with the growth rate at other times in history?
Compare and contrast the demographic transition in more developed and less developed countries.
How are population projections made?Hira Singh, Sandeep Kumar- Population Growth, Poverty and Unemployment in India: A Contemporary State Level Analysis EUROPEAN ACADEMIC RESEARCH - Vol. I, Issue 12 / March study period it has been found that despite performing well on the.
Population growth can be defined as an increase or decrease in the population size of living species including human beings. Human populations are also subject to natural process of birth and death. There has been a rapid increase in the worlds human population over the last few decades (UNFPA, ).
The rates of population growth are not the same, of course, in all parts of the world. Among the industrialized countries, Japan and most of the countries of Europe are now growing relatively slowly—doubling their populations in 50 to years.
Jul 26, · In , an analysis of United Nations data by the journal Science concluded that a halt to population growth in this century was unlikely and projected that between bn and bn people would be living on the planet by "Go Forth And Multiply!" That's what the human population has successfully been doing for thousands and thousands of years, expanding, exploring, migrating, conquering, utilizing, evolving, civilizing, industrializing, and now, destroying the very land upon which we live.
Growth from to was rapid—the global population nearly tripled, and the U.S. population doubled. However, population growth from to is projected to be significantly slower and is expected to tilt strongly to the oldest age groups, both globally and in the U.S.