Satellite imagery combined with ground based data and spatial mapping tools can make an enormous difference to agricultural decision making at global, national and local levels, by providing more timely and accurate information. Remotely sensed technologies are desirable because they have low marginal cost; they provide higher levels of spatial resolution than alternate approaches; they are the only feasible data gathering mechanism in some locations; they provide precise, automated repetition of data collection efforts; and they can be combined with geolocalised in-situ data collection to generate value-added products.
However, there are still many problems with existing products of croplands and rangelands, which are subject to rapid change, and in general, are poorly described using current general land cover maps, particularly in areas such as Africa. For this reason the workshop on Characterizing and Validating Global Land Cover was held at the International Institute of Applied Systems Analysis (IIASA) in Laxenburg, Austria from 13 to 15 June 2011 to consider improvements to cropland and rangeland mapping in Africa.
The workshop was hosted by IIASA and CGIAR CSI (Consortium for Spatial Information), in close collaboration with the Group on Earth Observation (GEO), the Agricultural Monitoring Communities of Practice (COP), GOFC-GOLD and the Joint Research Centre of the European Commission (JRC). The workshop was funded by the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS) and the JRC.
The workshop brought together more than 70 international experts on remote sensing, land cover (to consider issues of training, calibration and validation), land use, cropland and rangeland mapping, crop type mapping, area estimation and crowd-sourcing. Several international organizations were represented including FAO, IFPRI, ILRI and ICRISAT as well as universities and experts working in national agencies concerned with cropland and/or land cover/land use mapping.
The main objectives of the workshop were: a) to integrate the best land cover information that is currently available on cropland extent in order to create a hybrid map at a 1 km resolution shortly after the workshop; b) to build an improved land cover validation dataset by encouraging participants to contribute geo-tagged photos, validation points and existing reference validation datasets; and c) to build a continuing international collaboration via Geo-Wiki in the collection of data related to land cover validation.
The GOFC-GOLD Land Cover Implementation Team with the CEOS Land Product Validation Working Group held a two day meeting on validation at IIASA directly after this workshop (from 16-17 June 2011). The workshop provided a good link to the subsequent discussions of the latter meeting.
The workshop report can be be viewed or downloaded from here.
