Global population future Flashcards
(19 cards)
What is ozone depletion?
Ozone depletion is the thinning of the layer of ozone (O3) in the upper atmosphere that protects the earth from the sun’s shortwave ultraviolet radiation.
Define ultraviolet radiation (UVR).
Ultraviolet radiation is a type of solar radiation that can be harmful to human health in high doses.
What are the main health risks associated with increased UVR exposure?
The main health risks associated with increased UVR exposure are skin cancer and cataracts.
Has the ozone layer fully recovered since the Montreal protocol
The ozone layer is recovering but will take another 50 years to fully thicken to its original levels.
Define cataracts.
Cataracts are caused by the lens of the eye becoming cloudy, leading to blurred vision .
What factors increase the risk of skin cancer and cataracts?
Factors that increase the risk of skin cancer and cataracts include geographic location, time of day, and altitude.
What are the three main ways climate change impacts human health?
Direct impacts of extreme weather.
Indirect impacts of reduced environmental quality.
Indirect impacts of reduced mental health.
Define vector-borne diseases.
Vector-borne diseases are illnesses due to parasites, viruses, and bacteria that are transmitted by vectors like mosquitoes, ticks and flies.
Why do higher altitudes have higher UVR levels
At higher altitudes, UVR levels increase as there is less atmosphere to absorb the radiation.
What is the UN’s prediction for global population in 2050?
The UN predicts global population will reach 9.7 billion in 2050.
Define the fertility replacement rate.
The fertility replacement rate is the average number of children each woman needs to have to maintain current population levels, typically 2.1 children per woman.
What is a pro-natalist policy?
A pro-natalist policy is a government strategy aimed at encouraging higher birth rates.
What percentage of the global population is predicted to be over 60 by 2050?
Approximately, 25% of the global population (excluding Africa) is predicted to be over 60 by 2050.
What is one strategy used to manage declining populations in developed countries?
One strategy used to manage declining populations in developed countries is encouraging immigration of working age population.
What impact does educating women have on fertility rates?
Educating women tends to reduce fertility rates, as it gives women more career opportunities and less time for childbearing.
What does PRP model stand for
population resource and pollution model
What does he PRP model show
the relationship between people and the environment.
Natural resources provide goods and services to human populations, but the acquisition and the use of these resources disrupt environmental processes and produce pollution
What is a positive feedback loop example for the PRP model
Population growth leads to a need for more food, which drives an increase in food production.
The increase in food availability allows the population to increase further, as more people can be supported when there is more food. This leads to a further drive to improve yields, which leads to even higher food availability, which leads to more population growth… and so on.
An increased population results in more extraction of fossil fuels, so more fuel is available for transporting food to places where there are shortages. This decreases malnutrition and allows the population to increase.
What is a negative feedback loop example for the PRP model
Growing populations cause expansion and intensification of agriculture, which leads to increased soil erosion. This decreases agricultural yields as the soil becomes less fertile. Food production is no longer high enough to support the population, causing it to decline.
An increased population leads to increased extraction and use of fossil fuels for energy. Increased levels of greenhouse gases from burning fossil fuels cause climate change, which reduces rainfall and crop yields in some areas. This causes malnutrition, which reduces the population.
