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.
Demography: geographic study of population. Natural increase: births minus deaths in a given population. Crude birth rate (CBR or natality): number of live births per year per 1,000 people. Crude death rate (CDR): number of deaths per year per 1,000 people. Mortality: There are two useful ways to measure mortality; infant mortality rate and life expectancy. The IMR reflect a countrys health care system and life expectancy measures the average number of years a baby can expect to live.