Rapid Population Growth
Estimated size of human population from 10,000 BCE–2000 CE.
Population growth is the change in a population over time, and can be quantified as the change in the number of individuals of any species in a population using "per unit time" for measurement. In biology, the term population growth is likely to refer to any known organism, but this article deals mostly with the application of the term to human populations in demography.
In demography, population growth is used informally for the more specific term population growth rate (see below), and is often used to refer specifically to the growth of the human population of the world.
Simple models of population growth include the Malthusian Growth Model and the logistic model.
Population growth 1800-2011: from 1 billion to 7 billion estimated in 31.10.2011. During the year 2011, according to estimates:[1]
Year
|
Billion
|
1800
|
1
|
1927
|
2
|
1960
|
3
|
1974
|
4
|
1987
|
5
|
1999
|
6
|
2011*
|
7
|
2025*
|
8
|
2043*
|
9
|
2083*
|
10
|
* UNFPA
United Nations Population Fund
estimate 31.10.2011
135 million people were born
57 million people died
78 million people increased the world population.
Determinants of population growth
Population growth is determined by four factors, births(B), deaths(D), immigrants(I), and emigrants(E). Using a formula expressed as
∆P≡(B-D)+(I-E)
In other words, the population growth of a period can be calculated in two parts, natural growth of population (B-D) and mechanical growth of population (I-E),in which Mechanical growth of population is mainly affected by social factors, e.g. the advanced economies are growing faster while the backward economies are growing slowly even with negative growth.
[edit]Population growth rate
In demographics and ecology, population growth rate (PGR) is the rate at which the number of individuals in a population increases in a given time period as a fraction of the initial population. Specifically, PGR ordinarily refers to the change in population over a unit time period, often expressed as a percentage of the number of individuals in the population at the beginning of that period. This can be written as the formula:[2]
The most common way to express population growth is as a percentage, not as a rate. The change in population over a unit time period is expressed as a percentage of the population at the beginning of the time period. That is:
For small time periods and growth rates, the added population is the growth rate multiplied by the time period.
A positive growth ratio (or rate) indicates that the population is increasing, while a negative growth ratio indicates the population is decreasing. A growth ratio of zero indicates that there were the same number of people at the two times -- net difference between births, deaths a growth rate may be zero even when there are significant changes in the birth rates, death rates, immigrationrates, and age distribution between the two times. [3] Equivalently, percent death rate = the average number of deaths in a year for every 100 people in the total population.
If the length of the time is taken smaller and smaller, the PGR approaches the logarithmic derivative of the population function P. If the population as a function of time is exponential, say P(t) = Ceat, the logarithmic derivative is a. Thus, the PGR approximates the exponent a for populations with exponential growth.
A related measure is the net reproduction rate. In the absence of migration, a net reproduction rate of more than one indicates that the population of women is increasing, while a net reproduction rate less than one (sub-replacement fertility) indicates that the population of women is decreasing.
[edit]Excessive growth and decline
Main articles: Overpopulation and Population decline
Population exceeding the carrying capacity of an area or environment is called overpopulation. It may be caused by growth in population or by reduction in capacity. Spikes in human population can cause problems such as pollution and traffic congestion, these might be resolved or worsened by technological and economic changes. Conversely, such areas may be considered "underpopulated" if the population is not large enough to maintain an economic system (see population decline). Between these two extremes sits the notion of the optimum population.
[edit]Human population growth rate
Annual population growth rate in percent, as listed in the CIA World Factbook (2011 estimate).[4]
Growth rate of world population (1950-2050)
Population of the world from 10,000 BCE to 2000 CE (logarithmic scale)
Globally, the growth rate of the human population has been declining since peaking in 1962 and 1963 at 2.20% per annum. In 2009, the estimated annual growth rate was 1.1%.[5] The CIA World Factbook gives the world annual birthrate, mortality rate, and growth rate as 1.915%, 0.812%, and 1.092% respectively[6] The last one hundred years have seen a rapid increase in population due to medical advances and massive increase in agricultural productivity[7] made possible by the Green Revolution.[8][9][10]
The actual annual growth in the number of humans fell from its peak of 88.0 million in 1989, to a low of 73.9 million in 2003, after which it rose again to 75.2 million in 2006. Since then, annual growth has declined. In 2009, the human population increased by 74.6 million, which is projected to fall steadily to about 41 million per annum in 2050, at which time the population will have increased to about 9.2 billion.[11] Each region of the globe has seen great reductions in growth rate in recent decades, though growth rates remain above 2% in some countries of the Middle East and Sub-Saharan Africa, and also in South Asia, Southeast Asia, and Latin America.[12]
Some countries experience negative population growth, especially in Eastern Europe mainly due to low fertility rates, high death rates and emigration, as well as abortion. In Southern Africa, growth is slowing due to the high number of HIV-related deaths. SomeWestern Europe countries might also encounter negative population growth.[13] Japan's population began decreasing in 2005.[14]
[edit]Growth by country
According to United Nations population statistics, the world population grew by 30%, or 1.6 billion people, between 1990 and 2010.[15] As persons the increase was among highest in India 350 million and China 196 million. Population growth was among highest in the United Arab Emirates (315%) and Qatar (271%).[15]
Rank
|
Country
|
Population
2010 |
Population
1990 |
Growth (%)
1990-2010 |
World
|
6,895,889,000
|
5,306,425,000
|
30.0%
|
|
1
|
1,341,335,000
|
1,145,195,000
|
17.1%
|
|
2
|
1,224,614,000
|
873,785,000
|
40.2%
|
|
3
|
310,384,000
|
253,339,000
|
22.5%
|
|
4
|
239,871,000
|
184,346,000
|
30.1%
|
|
5
|
194,946,000
|
149,650,000
|
30.3%
|
|
6
|
173,593,000
|
111,845,000
|
55.3%
|
|
7
|
158,423,000
|
97,552,000
|
62.4%
|
|
8
|
148,692,000
|
105,256,000
|
41.3%
|
|
9
|
142,958,000
|
148,244,000
|
-3.6%
|
|
10
|
128,057,000
|
122,251,000
|
4.7%
|
[edit] 1960s to 2010 table of population growth
Population growth 1990-2008 (%)[16]
55 %
|
|
51 %
|
|
35 %
|
|
30 %
|
|
24 %
|
|
9 %
|
|
8 %
|
|
-1 %
|
|
Non-OECD Europe
|
-11 %
|
Many of the world's countries, including many in Sub-Saharan Africa, the Middle East, South Asia and South East Asia, have seen a sharp rise in population since the end of the Cold War. The fear is that high population numbers are putting further strain on natural resources, food supplies, fuel supplies, employment, housing, etc.; in some the less fortunate countries. The population of Chad has, for example, ultimately grown from 6,279,921 in 1993 to 10,329,208 in 2009,[17] further straining its resources. Vietnam, Mexico, Nigeria, Egypt, Ethiopia and the DRC are witnessing a similar growth in population.
The situation was most acute in northern, western and central Africa. Refugees from places like the Sudan have helped further strain the resources of neighbouring states like Chad and Egypt. The nation is also host to roughly 255,000 refugees from Sudan’s Darfur region, and about 77,000 refugees from the Central African Republic, whilst approximately 188,000 Chadians have been displaced by their own civil war and famines, have either fled to either the Sudan, the Niger or, more recently, Libya.
Example nation
|
1st Population
total.
|
2nd Population
total.
|
3rd Population
total.
|
4th Population
total.
|
5th Population
total.
|
Life expectancy
in years.
|
Total
population growth from 1st Pop. Total to 5th Pop. Total.
|
N/A*
|
N/A*
|
4,298,269 (2002)
|
2,236,520 (since independence)
|
||||
67,673,031(2003)
|
55,764,000
|
||||||
Sudan**
|
38,114,160 (2003)**
|
27,917,000
|
|||||
9,253,493(2003)
|
6,919,205
|
||||||
10,790,352 (2001)
|
11,760,252
|
||||||
129,934,911 (2002)
|
96,809,000
|
||||||
11,340,480(2002)
|
9,772,176
|
||||||
2,667,859 (2003)
|
2,241,000
|
||||||
9,967,215(2002)
|
10,104,597
|
||||||
1,367,124 (2000)
|
1,362,000
|
||||||
32,818,500 (2003)
|
23,061,874
|
||||||
The
DRC/Zaire
|
55,225,478 (2003)
|
54,563,439
|
|||||
70,712,345 (2003)
|
49,006,231
|
||||||
720,934 (2003)
|
409,000
|
||||||
2,967 (2003)
|
640
|
||||||
15,116,435 (2002)
|
17,224,200 (2011)
|
8,288,700
|
|||||
41,088,227 (2002)
|
26,734,397
|
||||||
174,468,575 (2000)
|
105,077,694
|
||||||
103,400,165 (2000)
|
66,651,757
|
||||||
844,330 (2001)
|
372,273
|
||||||
12,329 (2002)
|
3,272
|
||||||
2,695,867 (2003)
|
971,232
|
||||||
19,546,792 (2003)
|
11,066,508
|
||||||
3,510,484 (2002)
|
1,021,452
|
||||||
38,626,349 (2001)
|
6,248,000
|
||||||
10,106,017 (2002)
|
-142,000
|
||||||
7,707,495(2000)
|
-875,330
|
||||||
58,789,194 (2002)
|
7,020,048
|
||||||
Ireland/Éire
|
3,840,838 (2000)
|
1,586,698
|
|||||
1,286,975,468 (2004)
|
619,724,852
|
||||||
Japan***
|
127,333,002 (2002)
|
28,123,865
|
|||||
—
|
—
|
—
|
—
|
—
|
—
|
||
1,028,610,328 (2001)
|
The rapid population growth in Tanzania’s urban areas presents a challenge that should be tackled head-on now instead of waiting for things to get out of hand. It is estimated that 30 million people will be living in urban areas by 2050, up from the current 12 million. This is a good pointer to the magnitude of the task that urban planners must take on.
Thirty-nine years is not a long time in the development of the nation. This means that long-term measures have to be taken now to ensure that Tanzania’s urban areas will be habitable in the foreseeable future despite the rapid population growth anticipated in the next few decades.
Urban dwellers are currently grappling with all manner of problems, including an acute shortage of decent housing, spiralling crime, congestion on the roads, lack of clean and safe water and inadequate or crumbling infrastructure. This, to a large extent, is the result of poor urban planning.
Dar es Salaam is a good example of the effects of sloppy planning. The city is home to an estimated four million people, but its water supply system was designed to cater for only 500,000 people. It is no wonder, then, that water running out of a tap is now a rare sight in the city.
The city is also synonymous with unplanned development, with sub-standard dwellings sprouting up in their hundreds in unauthorised areas. Vast areas of the city have been transformed into slums and it seems that the authorities gave up the battle long time ago. The traffic situation is another nightmare, and it is not uncommon for one to spend hours on the road for trips that should normally take a few minutes.
The situation in Dar es Salaam is representative of what happens in other rapidly expanding cities such as Arusha, Mbeya, Mwanza and Tanga. We shudder to think what the situation will be like in 2050 if adequate measures are not taken now to keep up with the population growth.
Population growth poses major problems for Texas roads
The baby boom — that fat lump that has been moving through the demographic snake since the end of World War II — is now made up of people between 45 and 65 years old, give or take.
They are starting to retire, prompting some of the growing conversations about pensions. Their bodies are getting old, which explains some of the ballooning advertising about drugs for this or that. Seen all the hearing aid ads in the paper? Products for gray hair? Couples sitting in bathtubs next to lakes?
As of 2010, 13 percent of the nation’s population was 65 or older. By 2030, demographers reckon that group will account for 19.3 percent of the population. Boomers are not babies anymore — and there are some public policy ramifications.
Steve Murdock — a nerd of the best kind, and of the highest order — is one of those boomers. More to the point, he is a demographer, now at Rice University, with notches on his résumé that include heading the U.S. Census Bureau and working as the first official demographer of the state of Texas.
He is the kind of guy who shows up for a one-hour presentation with 150 slides in his PowerPoint deck. He does not show them all, but they are there if someone asks a question best answered by a screen full of numbers or a graphic.
Much of it seems esoteric, but Murdock has held the attention of policy makers for years because numbers drive policy. How many babies will there be? How many schools do we need, and where? How do you guess at caseloads for medical providers?
Here is one: What about traffic, and old people?
Murdock sees the number of drivers growing, which makes sense since the overall population will grow. Since the population will be older over all, he projects the number of drivers per 1,000 residents will grow. More adults per 1,000 means more drivers per 1,000.
How will congestion, construction and car accidents on the highways fare under exponential population growth?
And the fastest growth of any age group will be the gray-hairs — drivers 65 or older. Depending on the growth model for Texas — what you think migration will do, whether you think the state will be as magnetic as it has been for the last two decades — the over-65 driving population will grow by anywhere from 218 percent to 268 percent between 2005 and 2040. Put another way: A population that numbered about 1.8 million in Texas in 2005 will grow to somewhere between 5.7 million and 6.6 million in 2040.
That group is part of a bigger issue: If the state continues to grow like it has, we will need more roads. “We’re adding lots of bodies to roads that are already congested,” Murdock said.
And lots of them are older bodies. Texas, as with some other states, has a different set of laws for its oldest drivers; after age 85, for instance, they have to get their licenses renewed every 2 years instead of every 6, and everyone who is 79 or older has to do it in person instead of by mail or online.
That might get another look as more drivers get old. The Insurance Institute for Highway Safety says fatal crashes per mile driven “increase noticeably starting at age 70-74.”
The bright spot in the demographics-as-traffic-policy is on the other end, where the most dangerous drivers live. The number of drivers under 25 will have the lowest growth rate on the charts through 2040. Their crash rate per mile is five times the rate of seniors.
State laws might change as time progresses. Older drivers might turn out to be no real problem. The expected congestion on those roads might drive people to other forms of transportation. There is some evidence that elderly drivers self-police when they start losing skills, and do not drive as much.
Murdock’s focus is less on the age of the drivers — though he thinks the aging of his generation poses an interesting set of questions for future lawmakers — and more on the growth of the population, of their cars and of the need for roads.
The policy folks will have to work out what needs to be built and who is going to pay for it and who gets to drive on those roads once they are built. They will not be deciding alone: every politician knows that older voters vote like crazy.
The numbers drive policy, but they drive politics, too.
Population increase triggers start of year-long OCP review
BY PAUL J. HENDERSON, THE TIMES OCTOBER 2, 2012
What will Chilliwack look like in the year 2040?
Public engagement begins next month for the City of Chilliwack's year-long official community plan (OCP) review.
The trigger for the review, which was set in 1998, is that the city is approaching the 85,000 population milestone. At that time, the OCP was developed based on an ultimate planning threshold of 134,000 people.
The city's population hit 77,936 in 2011, an increase of 12.6 per cent from 69,216 in 2006, according to Statistics Canada.
In terms of development, the OCP's objectives put a focus on the preservation of farmland, the densification of urban areas and further focus on housing in the hillsides.
At Tuesday's afternoon meeting, Chilliwack city council was scheduled to hear a presentation about the OCP and how the process will unfold over the coming months.
While much of the OCP will likely remain unchanged after the review, a number of initiatives the city has undertaken in recent years will need to be considered. Some examples include: the 2011 Agricultural Area Plan, the 2010 Healthier Communities Strategic Action Plan, and the hillside development guidelines.
The project to review the OCP will be led by the planning and strategic initiatives department with support from other departments and the Chilliwack Economic Partners Corporation (CEPCO), in addition to some outside agencies.
There will be public meetings set to start as early as next month. This public engagement will be done "in a fun and purposeful way to discuss key issues, future growth scenarios, strategies and policies, and eventual OCP amendments," according to a staff report.
The entire OCP review process is expected to take a year with a new bylaw set to be adopted in November 2013.
Details on what the public engagement process will look like will be announced by the end of October. http://www.chilliwacktimes.com/news/Population+increase+triggers+start+year+long+review/7329972/story.html
Net overseas migration jumped by 22.8 per cent in the March quarter, pushing up Australia's population growth and containing a promise of more to come.
The migration surge has implications for government budgeting that had been based on no increase in our growth rate and for unemployment rates that have been held down by a fall in the working age population.
Today's Australian Bureau of Statistics demographics release shows the population growth rate bouncing from a low of 1.1 per cent in the year to March 2011 to 1.5 per cent in the latest March year with most of the gain coming from migration. And net overseas migration is still accelerating.
NOM increased by 18.2 per cent to 197,200 for the year to the end of March with the pace rising through the year. After the March quarter's 22.8 per cent increase, NOM growth in the four months to July indicated by arrival and departures figures was 24.5 per cent.
Advertisement
As suggested here back in May, the federal budget appeared to miss the population growth story. On the performance of the first seven months of this year, population growth for 2012 will be 1.6 per cent – and that's before rumoured policy initiatives to further revive the international student industry.
The surplus of births over deaths in the latest year was 149,600, an increase of 3 per cent. Making up the NOM rise were arrivals up by 9.5 per cent for the year to 459,800 while departures increased by only 3.7 per cent to 262,600.
The latest breakdown by state shows more of the same – resource-rich and skill-short Western Australia streaking ahead with annual population growth accelerating further to 3.1 per cent, then Queensland picking up at 1.7 per cent.
Victoria's growth was steady at the national average of 1.5 per cent and then came the laggards – New South Wales with 1 per cent, just ahead of South Australia's 0.9 per cent and Tasmania struggling to stay positive with 0.3 per cent. The ACT was up 1.9 per cent and the Northern Territory by 1.3 per cent.
WA's growth rate is extraordinary, which makes its relatively flat housing industry performance all the stranger.
The NSW government has targeted population growth as a means of lifting the state's economy – which means there remains a great deal to be done. While NSW continues to attract overseas migrants, it also continues to lose locals, mainly to Queensland. Some 17,800 more New South Welshfolk moved out of the most populous state compared to the rest of the nation.
The implications of the recovery in population growth are many. For a flat national housing construction industry, it contains the seeds of hope. Given the reality of our demographic changes as the baby boomers retire, it has the promise of salvation from an otherwise gloomy future of vastly higher taxes and diminished resources.
For a federal government desperate to achieve a nominal surplus, it provides the hope of increased revenue. For financially challenged state governments, the extra third-of-a-million people should mean improved GST collection – but also greater demand for services and infrastructure.
http://en.wikipedia.org/wiki/Population_growth
http://www.smh.com.au/business/migration-pushing-population-growth-higher-20120927-26n0t.html
http://www.chilliwacktimes.com/news/Population+increase+triggers+start+year+long+review/7329972/story.html
http://www.pegasusnews.com/news/2012/oct/02/population-growth-poses-major-problems-texas-roads/
http://thecitizen.co.tz/editorial-analysis/19-editorial-comments/26180-lets-keep-pace-with-population-growth.html
