World's surface water: evaporation and runoff
Because much of the world’s surface water is far from concentrations of human settlements, not all of it is readily usable.
Some facts concerning global freshwater concentrations:
- It is estimated that the freshwater available for human consumption varies between 12,500 km3 and 14,000 km3 each year (Hinrichsen et al., 1998; Jackson et al., 2001).
- Many countries in Africa, the Middle East, western Asia, and some eastern European countries ha...
26 Jan 2009 - by Phillippe Rekacewicz (Le Monde diplomatique), February 2006
Number of Disasters per Year
Trends in number of reported disasters. Much of the increase in the number of hazardous events reported is probably due to significant improvements in information access and also to population growth, but the number of floods and cyclones reported is still rising compared to earthquakes. Is global warming affecting the frequency of natural hazards?
06 Oct 2009 - by Riccardo Pravettoni, UNEP/GRID-Arendal
Water supply and demand in Nairobi
The bulk of water supply for Nairobi comes from Thika, Sasumua and Ruiru Dams, as well as the Kikuyu Springs. Over time water supply for the city has failed to meet demand. The current estimated water demand for Nairobi is 650 000 m3/day compared to the production of 482 940 m3/day (WRMA
2010). The difference between production and demand has been widening over time due to population growth, inadequacy of the carrying capacity of the distributio...
18 Mar 2011 - by Riccardo Pravettoni, UNEP/GRID-Arendal
Access to water in urban Africa
Improved water sources, defined as “one that is protected from outside contamination” (WHO/UNICEF 2010), is essential for ensuring the health of Africa’s urban dwellers. Although an increasing number of people have access to improved water, rapid urban population growth in the African region has equally increased the number of people without proper access.
18 Mar 2011 - by Riccardo Pravettoni, UNEP/GRID-Arendal
Pressures on the South African coast
Population growth puts pressure on coastal ecosystems. Increased population means growing demand for land for housing and infrastructure, increased use of living resources for food, and more use of available freshwater resources. The negative environmental impacts of the shipping industry also harm the coastal ecosystem. Impacts from shipping include oil spills and the discharge of ballast water and waste into the sea, which affect the quality of...
21 Jun 2011 - by Riccardo Pravettoni, UNEP/GRID-Arendal
Population growth in North Sumatra and Aceh 1920-2008
Overall population growth in the region has been very rapid during the past nine decades. In 1920, the human populations of Aceh and North Sumatra provinces were 736,348 and 1,961,678, respectively (Volkstelling 1922). By 2008, these had risen dramatically to 4,293,915 and 13,042,317 (BPS 2010a).
13 Sep 2011 - by Riccardo Pravettoni, UNEP/GRID-Arendal