气候变化领域集成服务门户(CCPortal): The climate impact of hydrogen-powered hypersonic transport

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DOI	10.5194/acp-22-14323-2022
	The climate impact of hydrogen-powered hypersonic transport
	Pletzer, Johannes; Hauglustaine, Didier; Cohen, Yann; Joeckel, Patrick; Grewe, Volker
发表日期	2022
ISSN	1680-7316
EISSN	1680-7324
起始页码	14323
结束页码	14354
卷号	22 期号:21 页码:32
英文摘要	Hypersonic aircraft flying at Mach 5 to 8 are a means for traveling very long distances in extremely short times and are even significantly faster than supersonic transport (Mach 1.5 to 2.5). Fueled with liquid hydrogen (LH2), their emissions consist of water vapor (H2O), nitrogen oxides (NOx), and unburned hydrogen. If LH2 is produced in a climate- and carbon-neutral manner, carbon dioxide does not have to be included when calculating the climate footprint. H2O that is emitted near the surface has a very short residence time (hours) and thereby no considerable climate impact. Super- and hypersonic aviation emit at very high altitudes (15 to 35 km), and H2O residence times increase with altitude from months to several years, with large latitudinal variations. Therefore, emitted H2O has a substantial impact on climate via high altitude H2O changes. Since the (photo-)chemical lifetime of H2O largely decreases at altitudes above 30 km via the reaction with O(D-1) and via photolysis, the question is whether the H2O climate impact from hypersonics flying above 30 km becomes smaller with higher cruise altitude. Here, we use two state-of-the-art chemistry-climate models and a climate response model to investigate atmospheric changes and respective climate impacts as a result of two potential hypersonic fleets flying at 26 and 35 km, respectively. We show, for the first time, that the (photo-)chemical H2O depletion of H2O emissions at these altitudes is overcompensated by a recombination of hydroxyl radicals to H2O and an enhanced methane and nitric acid depletion. These processes lead to an increase in H2O concentrations compared to a case with no emissions from hypersonic aircraft. This results in a steady increase with altitude of the H2O perturbation lifetime of up to 4.4 +/- 0.2 years at 35 km. We find a 18.2 +/- 2.8 and 36.9 +/- 3.4 mW m(-2) increase in stratosphere-adjusted radiative forcing due to the two hypersonic fleets flying at 26 and 35 km, respectively. On average, ozone changes contribute 8 %-22 %, and water vapor changes contribute 78 %-92 % to the warming. Our calculations show that the climate impact, i.e., mean surface temperature change derived from the stratosphere-adjusted radiative forcing, of hypersonic transport is estimated to be roughly 8-20 times larger than a subsonic reference aircraft with the same transport volume (revenue passenger kilometers) and that the main contribution stems from H2O.
学科领域	Environmental Sciences; Meteorology & Atmospheric Sciences
语种	英语
WOS研究方向	Environmental Sciences & Ecology ; Meteorology & Atmospheric Sciences
WOS记录号	WOS:000879814000001
来源期刊	ATMOSPHERIC CHEMISTRY AND PHYSICS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/273606
作者单位	Helmholtz Association; German Aerospace Centre (DLR); Delft University of Technology; UDICE-French Research Universities; Universite Paris Saclay; CEA; Centre National de la Recherche Scientifique (CNRS)
推荐引用方式 GB/T 7714	Pletzer, Johannes,Hauglustaine, Didier,Cohen, Yann,et al. The climate impact of hydrogen-powered hypersonic transport[J],2022,22(21):32.
APA	Pletzer, Johannes,Hauglustaine, Didier,Cohen, Yann,Joeckel, Patrick,&Grewe, Volker.(2022).The climate impact of hydrogen-powered hypersonic transport.ATMOSPHERIC CHEMISTRY AND PHYSICS,22(21),32.
MLA	Pletzer, Johannes,et al."The climate impact of hydrogen-powered hypersonic transport".ATMOSPHERIC CHEMISTRY AND PHYSICS 22.21(2022):32.