Appropriations now or hereafter provided for the National Weather Service shall be available for (a) furnishing food and shelter, without repayment therefor, to employees of the Government assigned to Arctic stations; (b) equipment and maintenance of meteorological offices and stations, and maintenance and operation of meteorological facilities outside the United States by contract or otherwise; (c) repairing, altering, and improving of buildings occupied by the National Weather Service, and care and preservation of