In a service-oriented geo scientific research environment, individual geospatial services must be chained together as Web geoprocessing workflows to solve a complex geoscientific problem. The development of Web geoprocessing workflows can be divided into three phases: process modeling, process model instantiation, workflow execution. Provenance, or called lineage, records the derivation history of a data product. This paper presents a provenance framework for Web geoprocessing workflows. Such a framework includes the provenance representation, provenance recording, provenance storage, provenance service, and provenance applications. The concept of "three levels of geospatial provenance" is used to advocate the categories of provenance at the knowledge, service, and data level. The three-level view addresses the derivation history in the three-phase development of Web geoprocessing workflows. The applications of provenance are demonstrated by allowing re-orchestration of geoprocessing workflows at different phases using different levels of provenance and creating a more flexible system for Web geoprocessing workflows.