The 8 billionth person was born on November 15th. It's more or less. The moment the world crossed its latest population milestone was chosen by the UN demographers. There are a billion more humans alive than there were 11 years ago.

I didn't pay much attention to the Day of 8 billion. The world has changed since there were just 7 billion of us, so it's important to focus on a few big numbers. Two examples are provided. Over the past 10 years, the proportion of people living in extreme poverty has declined. Only 9 percent of the world's population live on less than $2 a day, compared to 16.3% in 2010. GDP per capita and life expectancy have increased in India and China despite population growth. More people are living better lives today than ever before.

My inbox was filled with press releases warning of a planetary crisis as the Day of 8 Billion rolled around. I don't know why I was getting these stories. I wrote an article about why Musk is wrong to worry about population decline. demographers told me that the world's population is only going upwards. The real challenge is managing that increase. It put me firmly in the camp of journalists who are convinced that we should be less afraid of talking about population and the environment.

The coverage of the Day of 8 Billion came from the same point of view. The Guardian said that a population of 8 billion would have a grave impact on the climate. That is correct on a basic level. Carbon emissions will go up if everything else stays the same. Project Drawdown believes that by providing better family planning and education, it will be possible to avoid nearly 70 billion metric tons of CO 2 emissions by the year 2050.

When talking about population and climate change, we need to be careful. It is easy to see that there are too many people on the planet. Who are we talking about when we say overpopulation? Someone living in the US is responsible for 15 metric tons of CO 2 emissions every year. In countries where the majority of population growth will be concentrated, per capita emissions are less than in the US. Each person in the Democratic Republic of Congo produces less than 30 kilograms of CO 2 per year. Consumption is a factor that contributes to emissions.

The world's richest people emit the most greenhouse gasses. As emissions have fallen for the middle class in rich countries, those from the top 1 percent have gone up. According to a psychologist at the University of Bath, we don't have the ability to have more rich people on the planet. Reducing consumption in the developed world is the best way to reduce emissions.