; and (2) in consultation with relevant modal administrations, administer the programs described in subsections (a)(4) and (b)(2). (d) Treatment of funds Funds authorized to be appropriated by subsections (a) and (b) shall— (1) be available for obligation in the same manner as if those funds were apportioned under chapter 1 of title 23, United States Code, except that the Federal share of the cost of a project or activity carried out using those funds shall be 80 percent, unless otherwise expressly provided by this title (including the amendments by this title) or otherwise determined by the Secretary; and (2) remain available until expended and not be transferable, except as otherwise provided in this title. A Research and Development 5101. Highway research and development program (a) In general Section 503 of title 23, United States Code, is amended— (1) in subsection (a)(2) by striking section 508 and inserting section 6503 of title 49 ; and (2) in subsection (b)— (A) in paragraph (3)— (i) in subparagraph (A)— (I) in clause (ii) by striking ; and and inserting a semicolon; (II) in clause (iii) by striking the period and inserting ; and ; and (III) by adding at the end the following: (iv) to reduce greenhouse gas emissions and limit the effects of climate change. ; and (ii) by striking subparagraphs (D) and (E); (B) in paragraph (4)(A)— (i) in clause (ii) by striking ; and and inserting a semicolon; (ii) in clause (iii) by striking the period and inserting ; and ; and (iii) by adding at the end the following: (iv) to reduce greenhouse gas emissions and limit the effects of climate change. ; (C) in paragraph (5)(A)— (i) in clause (iv) by striking ; and and inserting a semicolon; (ii) in clause (v) by striking the period and inserting ; and ; and (iii) by adding at the end the following: (vi) reducing greenhouse gas emissions and limiting the effects of climate change. ; (D) in paragraph (8)(A) by inserting , ferry, after highway each place it appears