The Sierra Club wrote the linked article entitled: "3 things you didn’t know about global population and climate change", see extract. While the article seems to favor reducing consumption rather than limiting population growth (and to be real, politically there is no current will to control population by policy). Reading between the lines of the article for me raises several issue which may well increase the likelihood that we will not only exceed the current mean population projection of 9.7 billion people by 2050, but also that our collective carbon emissions will be higher than expected, including:
a. The article indicates that rights-based access to family planning may not limit consumption.
b. Women are more impacted by climate change, which translates in to them losing more control of their fertility, which means more population growth.
c. The article indicates that the death rate is decreasing which may well result in higher than expected population growth.
d. As the per capita carbon emissions is projected to increase significantly in the third world in the next several decades.
http://www.sierraclub.org/compass/2016/07/3-things-you-didn-t-know-about-global-population-and-climate-changeExtract: "Yesterday was World Population Day, to commemorate that, we took a look at global demographic trends and how they affect people and their environments.
1. Consumption plays a large role in contributing to climate disruption.
Often, when people talk about the impact of population on climate change, it is about the number of people. More people, more degradation. While this may carry truth for natural resources on a local level, the vast majority of climate emissions are a result of a handful of largely high-income countries. The United States for instance, while only five percent of the global population, produces 25 percent of the emissions. The average person in the United States produces 42 times the emissions of the average person in Bangladesh. On a national scale, that means the U.S. is producing 92 times more emissions than Bangladesh. The wealthiest 20 percent of people in the world consume 86 percent of its goods, with the poorest 20 percent consuming only 1.3 percent.
2. Population growth has dramatically slowed.
While population continues to grow, the rate of that growth has dramatically slowed. Today, our population is growing by 1.13 percent per year, nearly half the rate during peak growth in the late 1960s. While experts predict we’ll have 9.7 billion people by 2050, that represents a slowing of the population growth rate to an estimated half a percent growth.
Most of the continued growth we’ll witness through 2100 is based on population momentum. This is due to a lack of balance in births and deaths, largely attributed to a younger population. On global scale, more than half the world’s population is under the age of 30 and as youth enter reproductive years - even with a replacement rate of two children per woman - our population will grow. With these estimations, population will stop growing before the end of this century.
3. Climate disruption has increased impacts for women and girls.
Climate disruption is not gender neutral. It’s impact on women and girls is disproportionate. Women are an estimated 14 times more likely to die from a natural disaster, which fueled by climate disruption are growing in frequency and intensity. Women constitute up to 80 percent of global refugee and displaced populations, and typically in emergencies 70 to 80 percent of those needing assistance are women and children. As women, they are often the target of systematic rape, violence, and terror."
For projected increases in carbon emissions, see also:
http://www.eia.gov/forecasts/ieo/emissions.cfm