There shall be in the Department of Commerce an Under Secretary of Commerce for Oceans and Atmosphere who shall serve as the Administrator of the National Oceanic and Atmospheric Administration established by Reorganization Plan No. 4 of 1970 [5 U.S.C. App.] and perform such duties as the Secretary of Commerce shall prescribe. The Under Secretary shall be appointed by the President by and with the advice and consent of the Senate and shall be compensated at the rate now or hereafter provided for Level III of the Executive Schedule Pay Rates (5 U.S.C. 5314).