In 2015, for example, scientists said that an ongoing drought in Californiaâthe stateâs worst water shortage in 1,200 yearsâhad been intensified by 15 percent to 20 percent by global warming. They also said the odds of similar droughts happening in the future had roughly doubled over the past century.
Definition: Birth rate is the demographic measure of the rate at which children are born. The most well known is the crude birth rate, which is the number of births that occur each year per 1,000 people in the midyear population. It is called âcrudeâ because it does not take into account the possible effects of age structure.
Birth rates are an important indicator of and factor in development, and tracking trends in birth rates and fertility is critical to government planning. Birth and fertility rates, together with crude death rates, determine population growth. Historically, birth rates have fallen with economic development. It is no coincidence that countries with the highest birth, fertility and population growth rates are also among the poorest. Not one appears among the top 50 countries in terms of purchasing power parity.