气候变化领域集成服务门户(CCPortal): Nitrous Oxide Measurements SO243

CCPortal

DOI	https://doi.org/10.1594/PANGAEA.902087
	Nitrous Oxide Measurements SO243
	Arévalo-Martínez; Damian L; Ma; Xiao; Sun; Mingshuang; Bange; Hermann Werner
发布日期	2019-05-24
数据集类型	dataset
英文简介	The open ocean is a major source of nitrous oxide (N2O), an atmospheric trace gas attributable to global warming and ozone depletion. Intense sea-to-air N2O fluxes occur in major oceanic upwelling regions such as the eastern tropical South Pacific (ETSP). The ETSP is influenced by the El Niño–Southern Oscillation that leads to inter-annual variations in physical, chemical, and biological properties in the water column. In October 2015, a strong El Niño event was developing in the ETSP; we conduct field observations to investigate (1) the N2O production pathways and associated biogeochemical properties and (2) the effects of El Niño on water column N2O distributions and fluxes using data from previous non-El Niño years. Analysis of N2O natural abundance isotopomers suggested that nitrification and partial denitrification (nitrate and nitrite reduction to N2O) were occurring in the near-surface waters; indicating that both pathways contributed to N2O effluxes. Higher-than-normal sea surface temperatures were associated with a deepening of the oxycline and the oxygen minimum layer. Within the shelf region, surface N2O supersaturation was nearly an order of magnitude lower than that of non-El Niño years. Therefore, a significant reduction of N2O efflux (75 %–95 %) in the ETSP occurred during the 2015 El Niño. At both offshore and coastal stations, the N2O concentration profiles during El Niño showed moderate N2O concentration gradients, and the peak N2O concentrations occurred at deeper depths during El Niño years; this was likely the result of suppressed upwelling retaining N2O in subsurface waters. At multiple stations, water-column inventories of N2O within the top 1000 m were up to 160 % higher than those measured in non-El Niño years, indicating that subsurface N2O during El Niño could be a reservoir for intense N2O effluxes when normal upwelling is resumed after El Niño.
空间范围	Median Latitude: -10.903094 * Median Longitude: -79.145850 * South-bound Latitude: -16.075000 * West-bound Longitude: -85.500000 * North-bound Latitude: 1.000000 * East-bound Longitude: -75.274000
时间范围	2015-10-07T00:47:11 - 2015-10-20T01:05:30
语种	英语
国家	国际
学科大类	气候变化
学科子类	气候变化
文献类型	数据集
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/215858
推荐引用方式 GB/T 7714	Arévalo-Martínez,Damian L,Ma,et al. Nitrous Oxide Measurements SO243.2019-05-24.https://doi.org/10.1594/PANGAEA.902087.