Landscapes of West Africa: A Window on a Changing World is an atlas and unique dataset that uses time-series satellite image data and field-based photography to tell the story of wide-ranging land change across 17 countries. EROS scientists selected the years 1975, 2000 and 2013 to characterize the landscapes and create the product, which represents the broadest effort to map the region in history.
Landscapes of West Africa, A Window on a Changing World presents a vivid picture of the changing natural environment of West Africa. Using images collected by satellites orbiting hundreds of miles above the Earth, a story of four decades of accelerating environmental change is told. Widely varied landscapes — some changing and some unchanged — are revealing the interdependence and interactions between the people of West Africa and the land that sustains them. Some chapters of this atlas raise cause for concern, of landscapes being taxed beyond sustainable limits. Others offer glimpses of resilient and resourceful responses to the environmental challenges that every country in West Africa faces. At the center of all of these stories are the roughly 335 million people who coexist in this environment; roughly three times the number of people that lived in the same space nearly four decades ago.
This rapid growth of West Africa’s population has driven dramatic loss of savanna, woodlands, forests and steppe. Most of this transformation has been to agriculture. The cropped area doubled between 1975 and 2013. Much of that agriculture feeds a growing rural population, but an increasing fraction goes to cities like Lagos, Ouagadougou, Dakar and Accra as the proportion of West Africans living in cities has risen from 8.3 percent in 1950 to nearly 44 percent in 2015. The people of West Africa and their leaders must navigate an increasingly complex path, to meet the immediate needs of a growing population while protecting the environment that will sustain it into the future. This atlas contributes quantifiable information and meaningful perspective that can help guide West Africa and its people to a more sustainable future.
Learn more about the West Africa image Atlas here.
Case Study: Land Cover Modification
Land Productivity
What are the drivers?
Population
Climate
Case Studies Illustrating the Unique Changes Occurring in West Africa
Ecological Regions
Physical Geography
Biodiversity and Protected Areas in West Africa
Bioclimatic Regions Map
Landscape Restoration and Re-greening
Mangrove Changes
West Africa Land Use Land Cover Time Series
Below are publications associated with this project.
Landscapes of West Africa: A window on a changing world
The landscapes of West Africa—40 years of change
Mapping land cover through time with the Rapid Land Cover Mapper—Documentation and user manual
Map projections for global and continental data sets and an analysis of pixel distortion caused by reprojection
Map projections: A working manual
Below are partners associated with this project.
- Overview
Landscapes of West Africa: A Window on a Changing World is an atlas and unique dataset that uses time-series satellite image data and field-based photography to tell the story of wide-ranging land change across 17 countries. EROS scientists selected the years 1975, 2000 and 2013 to characterize the landscapes and create the product, which represents the broadest effort to map the region in history.
A savannah south of Kaffrine in central Senegal, photographed in 1994 Landscapes of West Africa, A Window on a Changing World presents a vivid picture of the changing natural environment of West Africa. Using images collected by satellites orbiting hundreds of miles above the Earth, a story of four decades of accelerating environmental change is told. Widely varied landscapes — some changing and some unchanged — are revealing the interdependence and interactions between the people of West Africa and the land that sustains them. Some chapters of this atlas raise cause for concern, of landscapes being taxed beyond sustainable limits. Others offer glimpses of resilient and resourceful responses to the environmental challenges that every country in West Africa faces. At the center of all of these stories are the roughly 335 million people who coexist in this environment; roughly three times the number of people that lived in the same space nearly four decades ago.
This rapid growth of West Africa’s population has driven dramatic loss of savanna, woodlands, forests and steppe. Most of this transformation has been to agriculture. The cropped area doubled between 1975 and 2013. Much of that agriculture feeds a growing rural population, but an increasing fraction goes to cities like Lagos, Ouagadougou, Dakar and Accra as the proportion of West Africans living in cities has risen from 8.3 percent in 1950 to nearly 44 percent in 2015. The people of West Africa and their leaders must navigate an increasingly complex path, to meet the immediate needs of a growing population while protecting the environment that will sustain it into the future. This atlas contributes quantifiable information and meaningful perspective that can help guide West Africa and its people to a more sustainable future.
Learn more about the West Africa image Atlas here.
- Science
Filter Total Items: 17
Case Study: Land Cover Modification
This work presents West Africa’s changing landscapes through land use and land cover maps for three periods in time. The changes between each period represent one of two main types of landscape change: land cover conversions and land cover modifications.Land Productivity
In contrast to the discrete land use and land cover classes, land productivity is a continuous variable, which represents land cover through vegetation density and vigor. Land productivity can indicate the land’s ability to support and sustain life and is useful for identifying land degradation. A common measure of land productivity is derived from time series of the Normalized Difference...What are the drivers?
Changes in land use and land cover result from a myriad of factors acting on the land surface.Population
With a 2015 population of 367 million (UN, 2015), West Africa is home to 5 percent of the world’s population. This is a five-fold increase in population since 1950, when 73 million people lived in the region, which makes West Africa the fastest growing of any of the world’s regions. For comparison, the world population has increased less than three-fold during the same time period. The young age...Climate
West Africa’s climate is controlled by the interaction of two air masses, the influence of which varies throughout the year with the north-south movement of the Intertropical Convergence Zone (ITCZ). Hot, dry continental air masses originating from the high pressure system above the Sahara Desert give rise to dusty Harmattan winds over most of West Africa from November to February. In summer...Case Studies Illustrating the Unique Changes Occurring in West Africa
Below is an example of a W-ARly-Pendjari (WAP) complex ecological case study illustrating the change over 30 years. There are 29 additional case studies available that explore the distinct transformations happening in the landscapes of West Africa, with one to two studies for each country. For the complete collection, refer to the Landscapes of West Africa Atlas.Ecological Regions
The map of ecological regions of West Africa captures the variety and complexity of West Africa’s landscapes and presents a way of organizing them into smaller units. Ecological regions, or ecoregions, are areas of relative homogeneity with respect to ecological systems involving the interrelationships of plants, animals, and their environment. Ecoregions are a holistic concept: The spatial...Physical Geography
The 8 million square kilometers and 17 countries covered by this atlas encompass a wide range of landscapes from alluvial valleys in Senegal and Ghana, sandy plains and low plateaus across the Sahel, and rolling hills of Togo to rugged mountains with summits reaching over 1,500 m in Guinea and 1,800 m in Niger. Covering approximately one quarter of Africa, West Africa contains a broad range of...Biodiversity and Protected Areas in West Africa
Biological diversity, or biodiversity, can be defined as the full array of life in a region, including species richness, ecosystem complexity, and genetic variation. Biodiversity may be the greatest natural resource, as it is a source of food, fuel, medicines, clothing, building materials, clean water, tourism and many other benefits (Norse and others, 1986). Biodiversity possesses marked economic...Bioclimatic Regions Map
From north to south — from the Sahara to the humid southern coast — West Africa can be subdivided into five broad east-west belts that characterize the climate and the vegetation. These are the bioclimatic zones known as the Saharan, Sahelian, Sudanian, Guinean, and Guineo-Congolian Regions, shown in the map above. The lines between these regions represent more of a transition along a continuous...Landscape Restoration and Re-greening
West Africa’s population is expected to double by 2050, increasing the demands on already limited land, water, and forest resources. The region’s landscapes are already affected by degradation, particularly in the fast growing agricultural lands where natural vegetation cover has been removed, and fragile soils have been exposed to wind and water erosion. Since 1975, West African forests have...Mangrove Changes
Mangroves are coastal forests that grow where ocean, freshwater, and land meet. They are among the most productive and complex ecosystems on the planet, thriving in salty and brackish conditions that would kill most other plants (Wetlands International, 2012). They have evolved clever mechanisms to enable them to cope with high concentrations of salt and the regular inundation of their root... - Data
West Africa Land Use Land Cover Time Series
This series of three-period land use land cover (LULC) 2-kilometer resolution datasets (1975, 2000, and 2013) aids in monitoring change in West Africa’s land resources (exceptions: Capo Verde at 500 meters, the Gambia at 1 kilometer and Tchad at 4 kilometers). To monitor and map these changes, a 26 general LULC class system was used. The classification system that was developed was primarily inspi - Publications
Below are publications associated with this project.
Landscapes of West Africa: A window on a changing world
Our global ecosystem is and has always been complex, dynamic, and in constant flux. Science tells us how natural forces of enormous power have shaped and reshaped Earth’s surface, atmosphere, climate, and biota again and again since the planet’s beginnings about 4.5 billion years ago. For most of the planet’s history those environmental changes were the result of the interaction of natural processAuthorsG. Gray Tappan, W. Matthew Cushing, Suzanne E. Cotillon, John A. Hutchinson, Bruce Pengra, Issifou Alfari, Edwige Botoni, Amadou Soulé, Stefanie M. HerrmannThe landscapes of West Africa—40 years of change
What has driven changes in land use and land cover in West Africa over the past 40 years? What trends or patterns can be discerned in those changes? To answer these questions, the U.S. Geological Survey West Africa Land Use Dynamics project partnered with the Permanent Interstate Committee for Drought Control in the Sahel and the U.S. Agency for International Development/West Africa to map land usAuthorsSuzanne E. CotillonMapping land cover through time with the Rapid Land Cover Mapper—Documentation and user manual
The Rapid Land Cover Mapper is an Esri ArcGIS® Desktop add-in, which was created as an alternative to automated or semiautomated mapping methods. Based on a manual photo interpretation technique, the tool facilitates mapping over large areas and through time, and produces time-series raster maps and associated statistics that characterize the changing landscapes. The Rapid Land Cover Mapper add-inAuthorsSuzanne E. Cotillon, Melissa L. MathisMap projections for global and continental data sets and an analysis of pixel distortion caused by reprojection
In global change studies the effects of map projection properties on data quality are apparent, and the choice of projection is significant. To aid compilers of global and continental data sets, six equal-area projections were chosen: the interrupted Goode Homolosine, the interrupted Mollweide, the Wagner IV, and the Wagner VII for global maps; the Lambert Azimuthal Equal-Area for hemisphere maps;AuthorsDaniel R. Steinwand, John A. Hutchinson, J.P. SnyderMap projections: A working manual
After decades of using only one map projection, the Polyconic, for its mapping program, the U.S. Geological Survey (USGS) now uses several of the more common projections for its published maps. For larger scale maps, including topographic quadrangles and the State Base Map Series, conformal projections such as the Transverse Mercator and the Lambert Conformal Conic are used. Equal-area and equidisAuthorsJohn P. Snyder - Partners
Below are partners associated with this project.