The Full Picture

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Global land cover observations

Martin Herold, Global Observation of Forest and Land Cover Dynamics (GOFC-GOLD)

n its ten-year reference document,

the Group on Earth

Observation (GEO) has highlighted the importance of land cover

for all areas of societal benefits. Land cover is one of the most

important elements for the description and study of the environment.

Reliable land cover observations are of crucial importance to under-

standing climate change and mitigating its impacts; to sustainable

development, natural resources management, conserving biodiver-

sity and understanding ecosystems and biogeochemical cycling.

Land cover change is an issue with far reaching policy implications, inter-

nationally, nationally and locally. For example, land cover characteristics

can indicate the ongoing processes of deforestation, desertification, urban-

ization, loss of biodiversity and ecosystem functions, and changing

boundary conditions for vector-borne diseases and water and energy

management. In situ and satellite-based land observation efforts across

disciplines (e.g. geography, ecology, geology, forestry, land policy and plan-

ning) use and refer to land cover as the most obvious and detectable

indicator of land surface characteristics.

Despite their importance, it is important to recognize that land obser-

vations are not operational in comparison to other earth observation

domains, such as oceans and atmosphere. The arena of land cover obser-

vations is heterogeneous in many ways – in terms of the

land surface itself, the approaches to acquire land cover data,

and the users of such information. Each land surface world-

wide has been mapped and characterized several times and

a large number of countries have a monitoring system in

place, including forest, agriculture and cartographic infor-

mation systems and inventories.

With the evolution of satellite-based observations, it has

become straightforward to produce land cover maps with a

reasonable amount of effort and little difficulty. To build a

sustained global land cover observing system, however,

requires international agreement and cooperation on the

continuity of global observations, the consistency in

mapping and monitoring specifications and land cover

assessment approaches, and sustained engagement and

participation inmapping activities, regional networking and

capacity building.

A role for GEO

The international land cover community has been working

withGEO since 2005 to build the foundations for land cover

observations as an integral part of the Global Earth

Observation Systemof Systems (GEOSS). Given the current

heterogeneity and lack of coordinated land cover observa-

tions globally, GEO has offered a platform for improvement

and has been driving observation progress, through:

• Highlighting the societal needs and relevance of land cover

observations

• Providing a forum for advocating global land cover and

change observations as key issues

• Fostering integrated perspectives for continuity and

consistency of land observations, in particular for joint

international efforts to provide baseline observations and

data suitable to assess global land cover and change

• Helping to evolve and apply international standards for

land cover characterization and validation

• Advocating joint participation in ongoing global mapping

activities, as well as regional networking and capacity

building in developing countries

• Helping to develop international partnerships involving

producers, users and the scientific community to better

produce and use existing datasets.

A specific task in the GEO2007-2009work plan (DA-07-02)

is dedicated to ‘global land cover’. The overall goal is to

provide a suite of global land cover datasets, initially based

on improved and validated moderate resolution land cover

maps and eventually including land cover change at high

resolution.

Key land cover observations

GEO SBA’s key land cover observation needs the multitude of benefits

from continuous and consistent global land cover observations

Source: M. Herold, GOFC-GOLD

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