Based on current growth rates, Earth's human population in 2019 will be closest to a. 2.5 million. b. 4.5 billion. c. 7.5 billion. d. 10.5 billion.

Verified step by step guidance

1. Identify the problem: The question asks for the closest estimate of Earth's human population in 2019 based on current growth rates.
2. Understand the context: As of recent years leading up to 2019, global population growth has been a significant topic in demographics, with estimates usually ranging in the billions.
3. Eliminate implausible answers: Option a (2.5 million) is far too low for a global population, which has been in the billions for decades. Option d (10.5 billion) is too high compared to recent growth trends.
4. Consider recent data: As of the late 2010s, the world population was estimated to be around 7 to 8 billion. This makes options b (4.5 billion) and c (7.5 billion) the most plausible.
5. Choose the best estimate: Given the trends and estimates around the year 2019, the closest and most accurate estimate would be option c, 7.5 billion.

Key Concepts

Human Population Growth

Human population growth refers to the increase in the number of individuals in a population. It is influenced by factors such as birth rates, death rates, immigration, and emigration. Understanding these dynamics is crucial for predicting future population sizes and addressing related challenges.

Demographic Transition Model

The Demographic Transition Model (DTM) describes the transition of a country from high birth and death rates to lower birth and death rates as it develops economically. This model helps explain population growth patterns and can be used to estimate future population sizes based on current trends.

Global Population Estimates

Global population estimates are statistical approximations of the number of people living on Earth at a given time. These estimates are derived from census data, surveys, and statistical models, and they provide insights into population trends, which are essential for planning resources and services.