Land Use and Land Cover Change
USGCRP Program Element

Land Use / Land Cover Change

Overview

Recent Accomplishments

Near-Term Plans

Archived News Postings [November 2002 - July 2005]

Related Sites

Calls for Proposals

CCSP / USGCRP Land Use & Land Cover Change Working Group Members

For long term plans, see chapter on Land Use / Land Cover Change of the Strategic Plan for the Climate Change Science Program (2003) posted on CCSP web site

Land use and land cover affect the global climate system through biogeophysical,
biogeochemical, and energy exchange processes. Variations in these processes due to land-use and land-cover change in turn affect local, regional, and global climate patterns. Key processes include uptake and release of greenhouse gases by the terrestrial biosphere through photosynthesis, respiration, and evapotranspiration; the release of aerosols and particulates from surface land-cover perturbations; variations in the exchange of sensible heat between the surface and atmosphere due to land-cover changes; variations in absorption and reflectance of radiation as land-cover changes affect surface reflectance; and surface roughness effects on atmospheric momentum that are land-cover dependent. Human activity can and does alter many of these processes and attributes, but weather and climate, as well as geological and other
natural processes, are also important.

For example, land-cover changes such as deforestation and forest fires alter ecosystems and release carbon dioxide, methane, carbon monoxide, and aerosols to the atmosphere. They also change the reflectivity of the land surface which in turn determines how much of the sun’s energy is absorbed and thus available as heat, while vegetation transpiration and surface hydrology determine how this energy is partitioned into latent and sensible heat fluxes. At the same time, vegetation and urban structure determine surface roughness and thus air momentum and heat transport.

Land-use and land-cover change studies also provide critical inputs to large-scale vegetation biomass and forest cover assessments that are key components of the carbon cycle. Future land-use and land-cover change goals include very accurate biomass estimates to refine knowledge of carbon storage in vegetation, understanding regional land-use changes that affect biomass, and quantifying linkages and feedbacks between land-use and land-cover change, climate change forcings, climate change, and other related human and environmental components.

Research that examines historic, current, and future land-use and land-cover change, their drivers, feedbacks to climate, and environmental, social, economic, and human health consequences is therefore of utmost importance and often requires interagency and intergovernmental cooperation. One example of a multi-agency effort is the Congo Basin Forest Partnership, which focuses on conserving the second largest tropical rainforest in the world in equatorial Africa. Satellite data are used to map forest extent, determine habitat fragmentation, and enforce conservation laws, and thus minimize greenhouse gas emissions from deforestation. Another example was the North America Land Cover Summit held in September 2006, which explored and encouraged collaboration among institutions and government agencies to advance the development and application of land-cover information in Mexico, the United States, and Canada [USAID, 2007: The Congo Basin Forests: State of the Forests 2006. Central African Regional Program on the Environment, U.S. AID, Washington, D.C., USA, 256 pp.]

See also: A Land Use and Land Cover Change Science Strategy.  Summary of a Workshop held at the Smithsonian Institution on 19-21 November 2003.  It was organized by the US Climate Change Science Program (CCSP) Land Use Interagency Working Group (LUIWG).  Edited by Richard Aspinall and Chris Justice. (posted 24 August 2005) Land-Use/Land-Cover Change [also available: PDF Version]. Chapter 6 from the Strategic Plan for the Climate Change Science Program (July 2003). Climate - Land Use/Land Cover Interactions.  Presentation from Breakout Session 6 of the US Climate Change Science Program: Planning Workshop for Scientists and Stakeholders, 3-5 December 2002, Washington, DC.  Carbon Cycle -- Ecosystems -- Land Use/Land Cover.  Presentation from Breakout Session 20 of the US Climate Change Science Program: Planning Workshop for Scientists and Stakeholders, 3-5 December 2002, Washington, DC.