I = PAT that human population may stabilize at around 11.2 billion in 2100, the I=PAT equation will continue to be relevant for the increasing human impact on the environment in the short to mid-term future. Increased population increases humans' environmental impact in many ways, which include but are not limited to: The variable A, in the I=PAT equation stands for affluence. It represents the average consumption of each person in the population. As the consumption of each person increases, the total environmental impact increases as well. A common proxy for measuring consumption is through GDP per capita. While GDP per capita measures
Population dynamics "λ" is the discrete-time per capita growth rate. At "λ" = 1, we get a linear line and a discrete-time per capita growth rate of zero. At "λ" < 1, we get a decrease in per capita growth rate. At "λ" > 1, we get an increase in per capita growth rate. At "λ" = 0, we get extinction of the species. Some species have continuous reproduction. where formula_5 is the rate of population growth per unit time, "r" is the maximum per capita growth rate, and "N" is the population size. At "r" > 0, there is an increase