Overpopulation is considered to be the result of improved medicine, sanitation and agriculture worldwide. In the early days of human history, the death rate was relatively close to the birth rate, ensuring a very slow population growth. As life spans improved due to advancements in technology, the birth rate began to grow much faster than the death rate, creating a larger surplus of births every year.Know More
The earliest factor that increased the population was the development of agriculture. Planting crops allowed communities to harvest food much more efficiently than hunting and gathering, providing a bulwark against starvation. With an abundance of food, people lived longer, and children were more likely to live to adulthood to reproduce. As technology has improved, the nutrition provided by the food supply has improved, as well, further increasing the lifespan and the reproductive potential of the population.
Modern medicine is another major factor in overpopulation. Major disease outbreaks are less common, and when they do occur, they tend to be much milder than in the past. Medical treatment allows people to survive illnesses that once would have killed them. Improved sanitation and access to clean water are also major factors that allow people to survive longer and reproduce.Learn more about Human Impact
The ozone layer is being damaged by pollutants in the air that are mostly man-made, such as chlorine and bromine. The ozone damage occurs in the stratosphere and troposphere. The lower pollution in the troposphere has many of the same causes as the upper destruction, but causes more visible and health-related issues than the stratosphere damage.Full Answer >
Climate change stems from numerous sources, including accumulation of greenhouse gases in the atmosphere, the burning of coal and fossil fuels and even some natural Earth activities such as volcanic eruptions. Some climate change comes from natural phenomena, including the changing path of Earth's orbit around the sun and extended heating and cooling phases. According to the Environmental Protection Agency, however, human activity, starting in the 20th century, greatly accelerates the rate of climate change.Full Answer >
Global warming is caused by an abundance of carbon dioxide in the Earth's atmosphere. The higher levels of carbon dioxide act the same as a blanket, keeping heat in and essentially warming up the temperature of the Earth. Carbon dioxide survives in the atmosphere for a long period of time.Full Answer >
Rain becomes acidic when it reacts with chemicals such as sulfur dioxide and nitrogen oxides that have been released into the atmosphere. The major reason for the increase in the occurrence of acid rain is human activity, although environmental reactions also sometimes cause acid rain.Full Answer >