Indexes of leading climate indicators for impact assessment

Could users of climate information for impact assessment be overlooking an important source of information in climate indicators? We argue that indexes of leading climate indicators of impacts may be usable knowledge for consumers and may provide guidance to the global climate observing community concerning the types of data and information that users need. Five classes of indexes are suggested: Climate Extremes Index (CEI) and Greenhouse Climate Response Index (GCRI) - such are already available from scientists at the U.S. National Climatic Data Center -plus proposed indexes of Hazard Warning, Ecosystem Health, and Energy Demand and Renewable Natural Resources. We conclude that the CEI and GCRI possess several necessary attributes to become usable knowledge; the other indexes have the potential to become usable knowledge, but remain to be implemented with climate data and fully evaluated.