; and (B) not less frequently than annually thereafter. (d) Definitions In this section, the definitions in section 47102 of title 49, United States Code, shall apply. 1090E. Conduct of winter season reconnaissance of atmospheric rivers in the western United States (a) Conduct of reconnaissance (1) In general Subject to the availability of appropriations, the 53rd Weather Reconnaissance Squadron of the Air Force Reserve Command and the Administrator of the National Oceanic and Atmospheric Administration may use aircraft, personnel, and equipment necessary to meet the mission requirements of the 53rd Weather Reconnaissance Squadron of the Air Force Reserve Command and the National Oceanic and Atmospheric Administration if those aircraft, personnel, and equipment are not otherwise needed for hurricane monitoring and response. (2) Activities In carrying out paragraph (1), the 53rd Weather Reconnaissance Squadron of the Air Force Reserve Command, in consultation with the Administrator of the National Oceanic and Atmospheric Administration and appropriate line offices of the National Oceanic and Atmospheric Administration, may— (A) improve the accuracy and timeliness of observations to support the forecast and warning services of the National Weather Service for the coasts of the United States; (B) collect data in data-sparse regions where conventional, upper-air observations are lacking; (C) support water management decisions and flood forecasting through the execution of targeted airborne dropsonde, buoys, autonomous platform observations, satellite observations, remote sensing observations, and other observation platforms as appropriate, including enhanced assimilation of the data from those observations over the eastern, central, and western north Pacific Ocean, the Gulf of Mexico, and the western Atlantic Ocean to improve forecasts of large storms for civil authorities and military decision makers