气候变化领域集成服务门户(CCPortal): Diverging responses of high-latitude co2and ch4emissions in idealized climate change scenarios

CCPortal

DOI	10.5194/tc-15-1097-2021
	Diverging responses of high-latitude co2and ch4emissions in idealized climate change scenarios
	De Vrese P.; Stacke T.; Kleinen T.; Brovkin V.
发表日期	2021
ISSN	19940416
起始页码	1097
结束页码	1130
卷号	15 期号:2
英文摘要	The present study investigates the response of the high-latitude carbon cycle to changes in atmospheric greenhouse gas (GHG) concentrations in idealized climate change scenarios. To this end we use an adapted version of JSBACH-the land surface component of the Max Planck Institute for Meteorology Earth System Model (MPI-ESM)-that accounts for the organic matter stored in the permafrostaffected soils of the high northern latitudes. The model is run under different climate scenarios that assume an increase in GHG concentrations, based on the Shared Socioeconomic Pathway 5 and the Representative Concentration Pathway 8.5, which peaks in the years 2025, 2050, 2075 or 2100, respectively. The peaks are followed by a decrease in atmospheric GHGs that returns the concentrations to the levels at the beginning of the 21st century, reversing the imposed climate change. We show that the soil CO2 emissions exhibit an almost linear dependence on the global mean surface temperatures that are simulated for the different climate scenarios. Here, each degree of warming increases the fluxes by, very roughly, 50 % of their initial value, while each degree of cooling decreases them correspondingly. However, the linear dependence does not mean that the processes governing the soil CO2 emissions are fully reversible on short timescales but rather that two strongly hysteretic factors offset each other-namely the net primary productivity and the availability of formerly frozen soil organic matter. In contrast, the soil methane emissions show a less pronounced increase with rising temperatures, and they are consistently lower after the peak in the GHG concentrations than prior to it. Here, the net fluxes could even become negative, and we find that methane emissions will play only a minor role in the northern highlatitude contribution to global warming, even when considering the high global warming potential of the gas. Finally, we find that at a global mean temperature of roughly 1.75 K (±0:5 K) above pre-industrial levels the high-latitude ecosystem turns from a CO2 sink into a source of atmospheric carbon, with the net fluxes into the atmosphere increasing substantially with rising atmospheric GHG concentrations. This is very different from scenario simulations with the standard version of the MPI-ESM, in which the region continues to take up atmospheric CO2 throughout the entire 21st century, confirming that the omission of permafrost-related processes and the organic matter stored in the frozen soils leads to a fundamental misrepresentation of the carbon dynamics in the Arctic. © 2021 Author(s).
英文关键词	carbon emission; climate change; concentration (composition); latitude; methane
语种	英语
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202296
作者单位	Land in the Earth System, Max Planck Institute for Meteorology, Hamburg, 20146, Germany; Institute of Coastal Research, Helmholtz-Zentrum Geesthacht, Geesthacht, 21502, Germany; Center for Earth System Research and Sustainability, University of Hamburg, Hamburg, 20146, Germany
推荐引用方式 GB/T 7714	De Vrese P.,Stacke T.,Kleinen T.,et al. Diverging responses of high-latitude co2and ch4emissions in idealized climate change scenarios[J],2021,15(2).
APA	De Vrese P.,Stacke T.,Kleinen T.,&Brovkin V..(2021).Diverging responses of high-latitude co2and ch4emissions in idealized climate change scenarios.Cryosphere,15(2).
MLA	De Vrese P.,et al."Diverging responses of high-latitude co2and ch4emissions in idealized climate change scenarios".Cryosphere 15.2(2021).