Figure 1: USA-NPN conceptual structure

Figure 1: USA-NPN conceptual structure

Figure 1: USA-NPN conceptual structure. The USA-NPN consists of four components or tiers, following the "Framework for Environmental Monitoring and Related Research" recommended by the Committee on Environmental and Natural Resources of the National Science and Technology Council. Each tier represents different levels of spatial coverage and related environmental information:

  1. Networks of locally intensive sites focused on process studies
  2. Spatially extensive environmental networks focused on standardized observations
  3. Volunteer and education Networks
  4. Remote sensing products that can be assimilated to extend surface observations
From: 
The USA National Phenology Network