The Big Picture: a Changing Planet
This group of indicators tracks important global driving forces that influence long-term changes at the global and Arctic scales. They provide information used in other focal points to analyze why some indicators are changing in the NWT. These changes can have significant direct and indirect effects on NWT environment.
This first focal point sets the stage for more detailed NWT indicators in other focal points.
Global climate indicators
Arctic climate indicators
Global demographic and economic indicators
Global climate indicators
1.1. Trends in global greenhouse gas concentrations
This indicator reports on global atmospheric concentrations of important long-lived greenhouse gases (GHGs) over the last 2,000 years.
This information is summarized from the Fourth Assessment Report of the International Panel on Climate Change - Climate Change 2007 - The Physical Science Basis published by the World Meteorological Organization and the United Nations Environment Programme.
NWT Focus
Increases in global GHG concentrations are partly responsible for the noticeable changes in the NWT’s climate during the past three decades, and are having complex effects on the NWT’s environment.
Current view: status and trend
- “Global atmospheric concentrations of carbon dioxide, methane and nitrous oxide have increased markedly as a result of human activities since 1750 and now far exceed pre-industrial values determined from ice cores spanning many thousands of years. The global increases in carbon dioxide concentration are due primarily to fossil fuel use and land use change, while those of methane and nitrous oxide are primarily due to agriculture.”
Quote from the Fourth Assessment Report of the International Panel on Climate Change - Climate Change 2007 - The Physical Science Basis Global: FAQ
Figure 1.1. Atmospheric concentrations of important long-lived greenhouse gases over the last 2,000 years. Increases since about 1750 are attributed to human activities in the industrial era. Concentration units are parts per million (ppm) or parts per billion (ppb), indicating the number of molecules of the greenhouse gas per million or billion air molecules, respectively, in an atmospheric sample. Source courtesy of: IPCC WG1- 2007 "The Physical Science Basis" Report;FAQ 2.1. Data from various sources, including from glaciers.
Looking forward
- “There is high agreement and much evidence that with current climate change mitigation policies and related sustainable development practices, global GHG emissions will continue to grow over the next few decades.”
- “Continued GHG emissions at or above current rates would cause further warming and induce many changes in the global climate system during the 21st century that would very likely be larger than those observed during the 20th century”
Quotes from the Fourth Assessment Report of the International Panel on Climate Change - Climate Change 2007 - The Physical Science Basis Global: Summary for Policy Makers
Find more
- For more information on global climate change go to the International Panel on Climate Change at http://www.ipcc.ch/
Other Focal Points
1.2. Trends in average global temperature, sea levels and snow cover
This indicator reports on measured changes in global average surface temperature and sea level, and changes in snow cover for March-April in the Northern Hemisphere.
This information is summarized from the Fourth Assessment Report of the International Panel on Climate Change - Climate Change 2007 - The Physical Science Basis published by the World Meteorological Organization and the United Nations Environment Programme.
NWT Focus
Increases in temperature and sea levels around the world are partly responsible for the noticeable changes in NWT’s climate during the past three decades, and are having complex effects on the NWT environment. Temperature and snow cover are compared to similar indicators at the NWT level in the CLIMATE and WEATHER focal point.
Current view: status and trend
- “At continental, regional and ocean basin scales, numerous long-term changes in climate have been observed. These include changes in arctic temperatures and ice, widespread changes in precipitation amounts, ocean salinity, wind patterns and aspects of extreme weather including droughts, heavy precipitation, heat waves and the intensity of tropical cyclones.”
- Eleven of the last twelve years (1995–2006) rank among the 12 warmest years in the instrumental record of global surface temperature (since 1850). The linear warming trend over the last 50 years … is nearly twice that for the last 100 years. The total temperature increase from 1850–1899 to 2001–2005 is 0.76°C.”
- “Average sea level rose at an average rate of 1.8 [1.3 to 2.3] mm per year over 1961 to 2003. The rate was faster over 1993 to 2003. …[How this trend] reflects decadal variability or an increase in the longer term trend is unclear.”
- “Mountain glaciers and snow cover have declined on average in both hemispheres. Widespread decreases in glaciers and ice caps have contributed to sea level rise (ice caps do not include contributions from the Greenland and Antarctic Ice Sheets).”
Quotes from the Fourth Assessment Report of the International Panel on Climate Change - Climate Change 2007 - The Physical Science Basis Global:
(a) Global average surface temperature, (b) global average sea level from tide gauge (blue) and satellite (red) data and (c) Northern Hemisphere snow cover for March-April. All changes are relative to corresponding averages for the period 1961–1990. Smoothed curves represent decadal average values while circles show yearly values. The shaded areas are the uncertainty intervals estimated from a comprehensive analysis of known uncertainties (a and b) and from the time series Source courtesy of: IPCC WG1 AR4 Report; Figure SPM.3.
Looking forward
- “For the next two decades, a warming of about 0.2°C per decade is projected for a range of SRES emission scenarios. Even if the concentrations of all greenhouse gases and aerosols had been kept constant at year 2000 levels, a further warming of about 0.1°C per decade would be expected. “
Quote from the Fourth Assessment Report of the International Panel on Climate Change - Climate Change 2007: - The Physical Science Basis Global:
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Other Focal Points
Arctic climate indicators
1.3. Projected trends in temperature and precipitation in the Arctic
This indicator reports on projected changes in Arctic temperature and precipitation based on climate change models.
This information is summarized from the Fourth Assessment Report of the International Panel on Climate Change - Climate Change 2007 - The Physical Science Basis published by the World Meteorological Organization and the United Nations Environment Programme.
NWT Focus
Changes in global climate can differin different parts of the world. This indicator provides more detailed observations and predictions on climate changes that are directly affecting the environment in the NWT.
Current view: status and trend
- “(Winters) …are likely to (get warmer)… in northern North America. “
- “Snow season length and snow depth are very likely to decrease in most of North America, except in the northernmost part of Canada where maximum snow depth is likely to increase.”
- “The uncertainties in regional climate changes over North America are strongly linked to the ability of (climate models) to reproduce the dynamical features affecting the region … Atmosphere-Ocean General Circulation Models exhibit large model-to-model differences in ENSO and NAO/Arctic Oscillation (AO) responses to climate changes. Changes in the Atlantic … are uncertain, and thus so is the magnitude of consequent reduced warming in the extreme north-eastern part of North America; cooling here cannot be totally excluded. The Hudson Bay and Canadian Archipelago are poorly resolved by (climate models), contributing to uncertainty in ocean circulation and sea ice changes and their influence on the climate of northern regions.”
Quotes from the Fourth Assessment Report of the International Panel on Climate Change - Climate Change 2007: - The Physical Science Basis Global: Chapter 11, p. 887
“Temperature anomalies with respect to 1901 to 1950 for the whole Arctic for 1906 to 2005 (black line) as simulated (red envelope) by MMD models incorporating known forcings; and as projected for 2001 to 2100 by MMD models for the A1B scenario (orange envelope). The black line is dashed where observations are present for less than 50% of the area in the decade concerned.” Source: courtesy of: IPCC WG1 AR4 Report Fig 11.18. ARC = Arctic
“… changes in surface air temperature (°C, left), precipitation (mm day–1, right) ... for winter (DJF, top) and summer (JJA, bottom) predicted by climate change models for 2080-2099 relative to 1980-1999. Stippling denotes areas of uncertainty in the models. The largest increase is predicted for the Arctic, where winters will be more than 7.5 °C warmer on average in 100 years. Source: courtesy of: IPCC WG1 AR4 Report Fig 10.9. Partial
- “The ensemble mean of the … models projects a general decrease in snow depth …as a result of delayed autumn snowfall and earlier spring snowmelt. In some regions where winter precipitation is projected to increase, the increased snowfall can more than make up for the shorter snow season and yield increased snow accumulation. Snow depth increases are projected by some (climate change models) over some land around the Arctic Ocean … and by some (regional climate models) in the northernmost part of the Northwest Territories (Figure 11.13).”
Quotes from the Fourth Assessment Report of the International Panel on Climate Change - Climate Change 2007: - The Physical Science Basis Global: Chapter 11, p. 892
“Percent snow depth changes in March (only calculated where climatological snow amounts exceed 5 mm of water equivalent), as projected by the Canadian Regional Climate Model (CRCM; Plummer et al., 2006), driven by the Canadian General Circulation Model (CGCM), for 2041 to 2070 under SRES A2 compared to 1961 to 1990. Source: courtesy of: IPCC WG1 AR4 Report Fig 11.13
Looking forward
- “The Arctic is very likely to warm during this century more than the global mean. Warming is projected to be largest in winter and smallest in summer. Annual arctic precipitation is very likely to increase. It is very likely that the relative precipitation increase will be largest in winter and smallest in summer.”
- “Interannual variability over North America is connected to two large-scale oscillation patterns, ENSO and the NAO/AO The … model projections indicate (more intense) polar vortex and many models project a decrease in the arctic surface pressure, which contributes to an increase in the AO/NAO index ; the uncertainty is large, however, due to the diverse responses of (climate models)… The …model projections indicate a shift towards (more) El-Niño like conditions.. There is a wide range of behaviour among the current models, with no clear indication of possible changes in the amplitude or period of El Niño.” (see Focal point NATURAL CLIMATE FLUCTUATIONS for definitions of ENSO, NAO/AO and El Niño).
Quotes from the Fourth Assessment Report of the International Panel on Climate Change - Climate Change 2007: - The Physical Science Basis Global: Chapter 11.
The authors of the overview document of the Arctic Climate Impact Assessment identified these key findings:
- “The Arctic climate is now warming rapidly and much larger changes are projected.
- Arctic warming and its consequences have worldwide implications.”
- Arctic vegetation zones are projected to shift, bringing wide-ranging impacts.
- Animal species' diversity, ranges, and distribution will change.
- Many coastal communities and facilities face increasing exposure to storms.
- Reduced sea ice is very likely to increase marine transport and access to resources.
- Thawing ground will disrupt transportation, buildings, and other infrastructure.
- Indigenous communities are facing major economic and cultural impacts.
- Elevated ultraviolet radiation levels will affect people, plants, and animals.
- Multiple influences interact to cause impacts to people and ecosystems.”
Quote from the 2004 Arctic Climate Impact Assessment. Policy Document.
These predicted impacts can be tracked using indicators described in the relevant focal points of the State of the Environment report.
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Other Focal Points
Updated: 1 May 2009
1.4. Observed and projected trends in Arctic sea ice.
This indicator reports on the extent of Arctic sea ice. The indicator also compares observed changes in the extent of sea ice to projected changes based on climate models.
This indicator is based on satellite data compiled by the US National Snow and Ice Data Centre, and provides analyses from their “State of the Cryosphere” website, Environment Canada’s “State of the Canadian Cryosphere”, and the Fourth Assessment Report of the International Panel on Climate Change - Climate Change 2007 - The Physical Science Basis published by the World Meteorological Organization and the United Nations Environment Programme.
NWT Focus
Changes in global climate are predicted to be greater and more rapid in the Arctic than elsewhere. This indicator provides more detailed observations and predictions on ice: an important habitat component for Arctic wildlife and an important factor affecting local and global climate. Changes in the formation of Arctic ice are affecting the NWT environment in a complex way.
This indicator provides information at a global level that can be compared with more detailed information for the NWT in the Focal Point CLIMATE and WEATHER.
Current view: status and trend
On September 15-16, 2007, at the time of the Arctic sea ice minimum, relatively cloud-free skies enabled the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra to observe much of the sea ice and open ocean throughout the Arctic. Overlaid onto the image are sea ice minima from 2007 (medium blue), the previous record low from 2005 (light blue), and the long-term average from 1979-2000 (gray). The 2007 minimum, which correlates closely with the ice visible through clouds in this image, fell substantially below previous records. Image by Terry Haran, National Snow and Ice Data Center, University of Colorado, Boulder, using NASA MODIS data.http://nsidc.org/sotc/sea_ice.html
Source: courtesy of: National Snow and Ice Data Center
Passive microwave-derived (SMMR / SSM/I) sea ice extent departures from monthly means for the Northern Hemisphere, January 1953 to October 2008. Image courtesy of Walt Meier and Julienne Stroeve, National Snow and Ice Data Center, University of Colorado, Boulder. http://nsidc.org/sotc/sea_ice.html
Source: courtesy of: US National Snow and Ice Data Center: Mean sea ice anomalies, 1953-2008
- ” Satellite data from the SMMR and SSM/I instruments have been combined with earlier observations from ice charts and other sources to yield a time series of Arctic ice extent from the early 1900s onward. While the pre-satellite records are not as reliable, their trends are in good general agreement with the satellite record and indicate that Arctic sea ice extent has been declining since at least the early 1950s.”
Quote from the National Snow and Ice Data Center Webpage
The largest reductions in sea ice occur on thick multi-year ice in summer. So far the sharpest decline in sea ice minimum cover occurred in 2007.
Reductions in sea ice cover during the fall minimum are not occurring at the same rate everywhere. The most rapid changes are occurring in the Arctic basin, north of Alaska, and in the Barents Sea, north Scandinavia. There is an actual increase in sea ice concentration in some areas, such as north of the Canadian Archipelago and west of Banks Island. This increased cover is mostly of thin first-year ice, which is being piled up by the normal clockwise motion of the entire Arctic ice pack called the Beaufort Gyre.
A reduction in sea ice thickness of about 43% was recorded between 1988 and 2005 was recorded. Thinning of sea ice is also measured as an increase in the proportion of first-year ice (thinner) compared to multi-year ice (thicker). This thinner ice is more mobile and its movement can be greatly influenced by storm activities and ocean currents. The vulnerability of thin ice to ocean currents was demonstrated by the dramatic and previously unobserved opening of a large flaw lead in the Beaufort Sea just off the western coast of Banks Island in December 2007 - January 2008.
In December 2007, a massive fracture of the Beaufort Ice pack was observed west of Banks Island. Source: Image from NOAA, courtesy of: Environment Canada, Canadian Ice Service, Education Corner, Beaufort Sea: http://www.ice.ec.gc.ca/app/WsvPageDsp.cfm?id=11892&Lang=eng
Reductions in ice cover and in ice thickness are resulting in increased vulnerability of Arctic coastal communities to storm surges and coastal erosion. Local knowledge studies indicate that the changes in sea ice are resulting in increasing dangers during off-shore travels, especially in Fall and Spring. Reduced sea ice, earlier break-up of sea ice and more fall storms have resulted to more shore erosion in the Inuvialuit Settlement Region.
Looking forward
Raw data and analyses are shared across the world, including with scientists in Canada. This information was used by the International Panel on Climate Change to make predictions about the future extent of sea ice in the Arctic based on climate models:
- “Arctic sea ice is very likely to decrease in its extent and thickness. It is uncertain how the Arctic Ocean circulation will change”
Quote from the Fourth Assessment Report of the International Panel on Climate Change - Climate Change 2007: - The Physical Science Basis Global: Chapter 11.
The effects of Arctic Ocean circulation on the rate of decline in Arctic sea ice have been extensively studied and are proving to have an important role in the extremely fast reduction of summer sea ice compared to what were expected based on climate change models:
- “Examination of the long-term satellite record dating back to 1979 and earlier records dating back to the 1950s indicate that spring melt seasons have started earlier and continued for a longer period throughout the year… Even more disquieting, comparison of actual Arctic sea ice decline to projections from the (Fourth Assessment Report of the International Panel on Climate Change -AR4) show that observed ice loss is faster than any of the …models have predicted …” .
Quote from the National Snow and Ice Data Center webpage.
Find More
- The National Snow and Ice Data Center webpage provides daily news and analysis of the Arctic Sea Ice based on passive microwave satellite data. They provide daily mosaic satellite images of Arctic sea ice conditions.
- For more information on Arctic Sea Ice go to the National Snow and Ice Data Center webpage (http://www.ipcc.ch/ipccreports/ar4-wg1.htm), go to the State of the Canadian Cryosphere (http://www.socc.ca/index_intro_e.cfm) for Canadian studies of sea ice, and to the Fourth Assessment Report of the International Panel on Climate Change for more information on projections of Arctic Sea ice using climate change models.
Other Focal Points
Updated: 1 May 2009
Global demographic and economic indicators
1.5. Trends in global population numbers
This indicator reports on actual changes in human populations on the planet. This information is summarized from the United Nation Year Book and information from the UN Population Division.
UN Yearbook series. Collage courtesy of UN.
NWT Focus
Increasing global human population is linked (directly and indirectly) to increases in greenhouse gas emissions, to changes in long-range contaminants in northern regions, including the NWT, and to changes in demands for the NWT’s resources. This global indicator is compared with similar indicators for the NWT in the DEMOGRAPHY focal point.
Current view: status and trend
By 2005, the estimated world population had reached 6.5 billion people and global population density was estimated as an average of 48 people per km2 of the earth’s land surface area. In contrast, the NWT population density is 0.036 people per km2.
Source: 1950-2005 population estimates courtesy of 2005 UN Statist. ics Yearbook
Projected estimates courtesy of Wikimedia Commons with data from UN World Population Prospects Vertical axis is logarithmic.
Looking forward
The global human population growth rate has been slowing down since the 1960s.
Other Focal Points
Updated: 1 May 2009
1.6. Trends in global supply and demand for northern natural resources.
This indicator reports on prices for some commodities that are important to the NWT economy. The natural resource price index provides an indicator of the global supply and demand for NWT’s main renewable and non-renewable resources that sell on the world market.
This information is summarized from a Statistics Canada report. The EnvironStats report ”Canada’s natural resource wealth at a glance” tracks the natural resource price index as measured by the “overall price change for the bundle of resources considered” . These resources are grouped as Energy ( natural gas, crude oil, oil sands* , and coal), Minerals ( gold-silver, nickel-copper, copper-zinc, lead-zinc, molybdenum, uranium, potash*, and diamonds), and Timber (timber stocks that are physically accessible and available for harvesting). Most of these resources are present in the NWT.
The fur price indicator tracks the average annual price obtained per marten pelt. Marten is the most important species in terms of revenue for the NWT’s fur industry. GNWT Industry, Tourism, and Invesment compiles information on pelts sold at international auctions in Canada.
* Potash is the only resource listed here that is not known to occur in the NWT.
NWT Focus
As prices fornatural resources go up or down, prospects for exploration and development and of some of the NWT resources also change. These driving forces have affected past land use patterns in the NWT, and will continue to affect the NWT environment in the future. Fur prices are one of the main causes for changing participation in the trapping portion of the traditional economy in the NWT.
Current view: status and trend
Energy, Minerals and Timber
- “Unless set by regulatory agencies or organizations, the price of any good or resource is typically determined by supply and demand. The supply of natural resources is usually fixed in the short-term. In the long-term, however, the supply is affected by a number of factors including changes in resource prices, advancement of extraction technologies as well as discoveries of new deposits and depletion of resources.’
- “On the other hand, demand for most natural resources is variable in both the short and long run, being affected by fluctuations in domestic and global economic factors. When resource demand rises in the short term, constraints on short-term supply can mean sharp increases in prices. This effect can be seen in the price index of natural resources …, which has been volatile over the past decade, mainly due to fluctuating demand.”
- “On average, the all-items natural resource price index grew more than 9% per year from 1997 to 2006. Declines in resource prices in 1998 and 2002 were related to the 1997/98 East Asian financial crisis, and the terrorist attack of September 11, 2001, which triggered slowdowns in the global economy. Between 2002 and 2006, the price index of natural resources increased rapidly.”
- “In recent years, the real GDP of India and China, the world’s two most populated countries, grew more than 8% a year. These countries are both large importers of natural resources. In particular, China’s demand for industrial raw materials has pushed up world energy and metal prices.”
- “Volatility in the energy resource price index was the main factor for the volatility in the all-items resource price index. During the last decade, the energy resource price index grew on average by 12% per year, followed by minerals (7%) and timber (2%).”
Quotes from Canada’s natural resource wealth at a glance.
Source: EnviroStats Vol. 1 no.3 2007. Statistics Canada. Chart 3 Natural resource price index. 1997-2006;
Marten Pelts
Fur prices increased steadily after the Second World War when a large influx of women in the job market created a strong demand for fur items that had previously only been available to the wealthy few. By the late 1980s the demand and price for furs had increased to an all-time high. Prices collapsed in the early 1990s with large-scale campaigns for the abolition of trapping and changes in the fashion industry. By 2000, the price of marten pelts had returned to about the same value, accounting for inflation, as the 1960s. China is a major importer of Canadian furs. With the increase in the Chinese economy, the price of fur has increased in the past decade and by 2005-06 had reached the same level seen in the early 1980s.
Source: GNWT ITI - Average price of marten fur pelts sold at international auctions (pink). Adjusted (blue) for inflation to 2008 equivalent in Canadian dollars using the Bank of Canada Inflation calculator at http://www.bankofcanada.ca/en/rates/inflation_calc.html For example, due to inflation, receiving $6.71 for a pelt in 1958 was equivalent to receiving $51.53 for it in 2008.
Looking forward
- “When prices increase, businesses not only boost production to earn profits but also invest more in exploration and drilling activities. This may result in the discovery of new deposits. Also, with increased prices, previously known but unprofitable resources may become profitable to extract, which in turn increases the size of the economically recoverable reserve.”
On the other hand, when prices decrease, exploration and production decrease.
- “From 1997 to 2006, the all-items extraction cost index grew, on average, by 10% per year. This increase was mainly due to the increase in labour and capital costs in recent years.”
Quotes from Canada’s Natural resource wealth at a glance.
The price of pelts on international markets can vary with the global economy and fashion. They also vary depending on winter weather. Warm winters in China and other major fur buying areas result in low fur sales. Warm winters in the NWT produce poor quality furs, resulting in low prices. On the other hand, an extremely cold or snowy season may reduce pelt availability, increase demand and increase price. Competition from the wage economy can also reduce the number of furs harvested, reducing supply and increasing price. How weather and competition will affect the future of the trapping industry in the NWT is uncertain.
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Other Focal Points
Updated: 1 May 2009
Reference List
- 2008, National Snow and Ice Data Centre, University of Colorado Boulder, CO, http://nsidc.org/sotc/sea_ice.html
- 2008, State of the Canadian Cryosphere, Environment Canada, http://www.socc.ca/seaice/seaice_hist_e.cfm
- 2008, World Population, Wikimedia Foundation Inc.. http://en.wikipedia.org/wiki/World_population#cite_note-8
- Arctic Council, 2004, Arctic Climate Impact Assessment., Arctic Council. http://www.acia.uaf.edu/
- Barber, D. G. Lukovich J. V. Keogak J. Baryluk S. Fortier L. Henry G. H. R., 2008, The changing climate of the Arctic, Arctic, 61,(suppl. 1):7- 26
- Bureau of Statistics, 1-6-0007, Northwest Territories - 2007...by the Numbers, Government of the Northwest Territories.
- Communities of Aklavik, Inuvik Holman Island Paulatuk and Tuktoyaktuk Nickels S. Buell M. Furgal C. Moquin H., 2005, Unikkaaqatigiit – Putting the Human Face on Climate Change: Perspectives from the Inuvialuit Settlement Region., Ottawa:Joint publication of Inuit Tapiriit Kanatami, Nasivvik Centre for Inuit Health and Changing Environments at Université Laval and the Ajunnginiq Centre at the National Aboriginal Health Organization. http://www.itk.ca/sites/default/files/Inuvialuit.pdf
- Environment Canada, 2009, Education Corner, Beaufort Sea, Environment Canada, Canadian Ice Service website, http://www.ice.ec.gc.ca/app/WsvPageDsp.cfm?id=11892&Lang=eng
- International Panel on Climate Change., 2007, Climate Change 2007 - The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change , Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller, World Meteorological Organization and the United Nations Environment Programme, Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. http://www.ipcc.ch/http://ipcc-wg1.ucar.edu/wg1/wg1-report.html
- Islam, Kari, 2007, Canada's natural resource wealth at a glance, EnviroStats, 1,(3):4- 5 http://www.statcan.ca/english/freepub/16-002-XIE/16-002-XIE2007003.pdf
- Manson, G. K. and Solomon, S. M., 2007, Past and future forcing of Beaufort sea coastal change, Atmosphere-Ocean, 45,(2):107- 122
- Pearce, T. D, Smit, B., Duerden, F., Ford, J., Goose, A., Inuktalik, R., and Kataoyak, F., 2006, Community adaptation and vulnerability to climate change in Ulukhaktok., Conference and Youth Forum 11-18 August 2006, Tuktoyaktuk, Northwest Territories,
- United Nations Population Division, 2007, World population prospects: The 2006 revision population database.
- United Nations Population Division, 2007, World population prospects: The 2006 revision population database.
- United Nations Statistics Division, 2005, United Nation Demographic Yearbook, 2005 Regular Issue, http://unstats.un.org/unsd/demographic/products/dyb/dyb2.htm