See posted comments (0) Post a Comment Kampala

Uganda

Due primarily to high rural to urban migration, Kampala’s population has grown at an average rate of 5.6 percent annually since the 1960s; expanding its urban footprint to a sprawling 197 square kilometers. Over 1.2 million people now live in the capital city. This stunning growth can be seen in the remarkable contrast between these 1974 and 2008 satellite images. The growing population has led unplanned settlement and inadequate infrastructure for many of the City’s residents. In addition, areas of forest in and around the capital have been lost to increasing demand for charcoal. Many of the wetlands in the Kampala area have been lost to industrial and residential development. This has had a negative impact on water quality within Kampala as well as the water of Murchison Bay which has experienced periodic infestations of water hyacinth and massive algae blooms which turn the water of the bay green. View Detailed information

See posted comments (0) Post a Comment Dadaab Refugee Camp

Kenya

Ifo, Dagahaley, and Hagadera refugee camps are located in Dadaab town in the North Eastern Province of Kenya, near the border with Somalia. The camps date back to 1991 when civil wars erupted on a large scale in Somalia. The conflicts, along with prolonged drought, forced more than 400 000 people from Somalia to flee to Kenya and another 500 000 to other neighboring countries. The 1987 image shows a fairly intact landscape dominated by shrub vegetation characteristic of the semiarid area. In the 2000 image, the Ifo, Dagahaley, and Hagadera refugee camps stand out distinctly, revealing the presence of over 100 000 refugees and the impact of a high concentration of people on the environment. Shrublands have been reduced largely to bare spots with sparse and stunted shrubs and grasses, while riverine vegetation has also suff ered loss and degradation. View Detailed information

See posted comments (0) Post a Comment Budongo Forest Reserve

Uganda

A study in the Budongo Forest/Murchison Falls National Park landscape shows that there has been both woody cover decrease and increase. In areas where there has been continuous burning, woody cover species have changed from those that are less resistant to fire to those that are more resistant. The burning was mainly carried out by the local communities bordering the forest. In the northern portion of Budongo, an increase in policing of the forest area and the presence of a park entry gate has resulted in an observable decrease in burning. Signs of fire are evident in such landscapes as dark reddish purple scars. Fire scars were evident on the 1973 image of northern Budongo. There are almost no fire scars on the 2008 image. The areas where there has been a higher control of burning are the areas which have seen an increase in woody cover. View detailed information

See posted comments (0) Post a Comment Okavango Delta and Lake Ngami

Botswana

The vast stretches of grassland, wetland, and open water of the Okavango Delta are home to a variety of wildlife and vegetation as well as several native tribes. Although the Okavango ecosystem is considered one of the wonders of the world and attracts tourists from all over the globe, it faces several significant threats. Proposed upstream water projects are among these threats. The Okavango River originates in the highlands of east-central Angola and brings the flood waters and sediment necessary to maintain the dynamic flooding of the delta. Upstream dams could trap much of this sediment, causing the river View detailed information

See posted comments (0) Post a Comment Kangerdlugssuaq Glacier

Kangerdlugssuaq, the largest outlet glacier on Greenland’s east coast, is one of 12 fast flowing outlet glaciers that discharge ice into the surrounding oceans. Its rate of flow more than doubled between 2000 and 2005 reaching a speed of 14 km per year or 1.6 meters per hour. It has since slowed. During this same period mean summer temperature at coastal weather stations along southeastern Greenland increased 1.1° C. While the mechanisms controlling the rate of flow are complex and not fully understood, there is a general consensus that warming temperatures are driving the increased rates of discharge. The fronts of glaciers throughout southeast Greenland also receded rapidly during this same time period; an average retreat of 24 m/yr increasing to an average of 175 m/yr. Kangerdlugssuaq Glacier, which had been retreating 25 to 100 meters per year in the period between 1992 and 2000, retreated more than 4 km between April 2004 and April 2005. The loss of the Greenland Ice sheet is a major factor in projecting the sea level rise which might result from global warming. Loss of the entire sheet would raise global sea level an estimated 7 meters. If melting were the only mechanism through which Greenland was losing ice mass, this could take 1000s of years. The acceleration of Greenland’s glaciers raises concerns that the global sea level may rise more rapidly under global warming scenarios than had previously been estimated. View detailed information

See posted comments (0) Post a Comment Mendenhall Glacier

Mendenhall Glacier flows 22 kilometers from an elevation of nearly 1,600 meters in the Coast Mountain Range, to just above sea level at its terminus roughly 5 kilometers northeast of Juneau, Alaska. It has been receding since the 1700s when the “Little Ice Age” ended, retreating approximately 3 kilometers in the past century. Most of this retreat occurred in the mid-1940s and the late 1990s. The majority of the global community now accepts fluctuations in glaciers, particularly changes in their volume, to be reliable indications of a global trend of warmer air temperatures. While the retreating tongues of glaciers are less directly linked to climate change than overall volume, they are much more readily observed and allow the study of glaciers which would otherwise be out of the reach of most research projects. It is believed that the current climate conditions will not be reflected in most glacier tongues for years and will eventually amount to a kilometer or more of additional retreat. If climate conditions continue to follow current trends many glaciers will disappear completely. The satellite images from 1986 and 2007 show the continuing retreat of Mendenhall Glacier. Similar changes are taking place in many of the glaciers in southeastern Alaska. A 2002 study estimated the contribution of melting Alaska glaciers to sea level rise between the 1950s and 1990s to be twice that of the melting of Greenland’s ice sheet during the same time period. View detailed information

See posted comments (2) Post a Comment Great Man-made River Project, Al Kufra

Libyan Arab Jamahiriya

In the 1950s, oil exploration in Libyan Arab Jamahiriya turned up another resource beneath the scorching sands: the Nubian Sandstone Aquifer System. Radiocarbon analysis showed that some of the water in the aquifer system was 40 000 years old. Tapping the aquifers was chosen as the most cost-effective option for meeting the country's water needs. In 1993, Phase I of the Great Man-made River (GMMR) Project brought water from eastern well-fields at Sarir and Tazerbo to Benghazi (not shown). In 1996, Phase II brought water from well-fields at Jebel Hassouna to Tripoli (not shown). Phase III is still under construction. The project's largest reservoir, known as the Grand Omar Mukhtar, is located at Suluq (2006 image, yellow arrows). When fully operational, the GMMR will pump 3.6 million cubic metres of the Nubian Aquifer water per day. Water from the aquifer is used to support extensive centre-pivot irrigation agriculture at Al Kufra (see 1972 and 2001 images above). At current extraction rates the Nubian Sandstone Aquifer System is not likely to be depleted for a thousand years. Nevertheless, it is shared among four African nations: Libyan Arab Jamahiriya, Chad, Sudan, and Egypt. The concern of environmentalists is that eventually people will drain the aquifer faster than nature can renew it. The International Atomic Energy Agency is trying to bring the four countries together to plan rational shared use of the water. View detailed information