How to obtain sensor observation data easily and quickly is one of the challenging research areas in the Earth science community. Data and Sensor Planning Service aims to generate requirements on Earth observations data from which the geophysical products needed by Earth science models can derive. Then, the service discovers relevant data sources which meet these requirements, schedules data acquisition by ordering and retrieving data from these sources, and processes and returns the customized data which will be used in the Earth science models. In this general framework, Sensor Web Enablement specifications of Open Geospatial Consortium are implemented and integrated with other open Web geospatial data services seamlessly to access real or virtual Earth observation sensors. Additionally, an Ajax-enabled browser client is built to facilitate the standard sensor Web operations, user account management along with data acquisition. The prototype system is demonstrated to retrieve near real-time satellite observation data from Comprehensive Large Array-data Stewardship System through standard Web services, and also is applied in the bird migration model which uses climate data, vegetation data, as well as other remotely sensed and in-situ observation data to determine the bird migration routes and identify the possible resting areas.