scholarly journals Changing lower stratospheric circulation: The role of ozone and greenhouse gases

1998 ◽  
Vol 103 (D10) ◽  
pp. 11251-11261 ◽  
Author(s):  
Hans-F. Graf ◽  
Ingo Kirchner ◽  
Judith Perlwitz
2021 ◽  
pp. 1-13
Author(s):  
Kehan Li

Climate change is of great importance in modern times and global warming is considered as a significant part of climate change. It is proved that human’s emissions such as greenhouse gases are one of the main sources of global warming (IPCC, 2018). Apart from greenhouse gases, there is another kind of matter being released in quantity via emissions from industries and transportations and playing an important role in global warming, which is aerosol. However, atmospheric aerosols have the net effect of cooling towards global warming. In this paper, climate change with respect to global warming is briefly introduced and the role of aerosols in the atmosphere is emphasized. Besides, properties of aerosols including dynamics and thermodynamics of aerosols as well as interactions with solar radiation are concluded. In the end, environmental policies and solutions are discussed. Keywords: Climate change, Global warming, Atmospheric aerosols, Particulate matter, Radiation, Environmental policy.


Author(s):  
C.J. Newbold ◽  
A.R. Moss ◽  
G.S. Mollinson

Increasing concern over the role of greenhouse gases in global warming has lead to a renewed interest in the production of methane by ruminants. Sheep are routinely used to study digestibility, however their use as a model to study methane production by cattle has received only limited attention (Blaxter and Wainman, 1964). The objective of the current study was to establish whether differences in methane production exist between sheep and cattle and to measure the magnitude of these differences under various dietary situations.


2020 ◽  
Vol 20 (9) ◽  
pp. 5837-5859
Author(s):  
Rostislav Kouznetsov ◽  
Mikhail Sofiev ◽  
Julius Vira ◽  
Gabriele Stiller

Abstract. The paper presents a comparative study of age of air (AoA) derived from several approaches: a widely used passive-tracer accumulation method, the SF6 accumulation, and a direct calculation of an ideal-age tracer. The simulations were performed with the Eulerian chemistry transport model SILAM driven with the ERA-Interim reanalysis for 1980–2018. The Eulerian environment allowed for simultaneous application of several approaches within the same simulation and interpretation of the obtained differences. A series of sensitivity simulations revealed the role of the vertical profile of turbulent diffusion in the stratosphere, destruction of SF6 in the mesosphere, and the effect of gravitational separation of gases with strongly different molar masses. The simulations reproduced well the main features of the SF6 distribution in the atmosphere observed by the MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) satellite instrument. It was shown that the apparent very old air in the upper stratosphere derived from the SF6 profile observations is a result of destruction and gravitational separation of this gas in the upper stratosphere and the mesosphere. These processes make the apparent SF6 AoA in the stratosphere several years older than the ideal-age AoA, which, according to our calculations, does not exceed 6–6.5 years. The destruction of SF6 and the varying rate of emission make SF6 unsuitable for reliably deriving AoA or its trends. However, observations of SF6 provide a very useful dataset for validation of the stratospheric circulation in a model with the properly implemented SF6 loss.


2002 ◽  
Vol 29 (10) ◽  
pp. 138-1-138-4 ◽  
Author(s):  
Nathan P. Gillett ◽  
Myles R. Allen ◽  
Keith D. Williams

2016 ◽  
Author(s):  
Guangcheng Chen ◽  
Bin Chen ◽  
Dan Yu ◽  
Yong Ye ◽  
Nora F. Y. Tam ◽  
...  

Abstract. Mangrove soils have been recognized as sources of atmospheric greenhouse gases but the atmospheric fluxes are poorly characterized, and their adverse warming effect has scarcely been considered with respect to the role of mangrove wetlands in mitigating global warming. The present study balanced the warming effect of soil greenhouse gas emissions with plant carbon dioxide (CO2) sequestration rate in a highly productive mangrove wetland in South China to assess the role of mangrove wetland in mitigating atmospheric warming. The results showed that mangrove soils were significant sources of greenhouse gases, and the fluxes were significantly higher in summer and also different among mangrove sites. Gases fluxes were positively correlated with the soil organic carbon, total nitrogen, and NH4+-N contents. The mangrove plant was able to sequester a considerable amount of atmospheric CO2 at 5930 g CO2 m−2 yr−1 in the present study, and the ecosystem was source of methane (CH4) and nitrous oxide (N2O) gases but more intense CO2 sink. However, the warming effect of soil gas emissions, equivalent to 1222 g CO2 m−2 yr−1, was able to offset a large proportion (~22 %) of plant CO2 sequestration, and the two trace gases comprised ~24 % of the total warming effect. We therefore propose the assessment of the direct mitigation of atmospheric warming by mangrove ecosystem that should take into account both soil greenhouse gases emissions and plant CO2 sequestration.


2001 ◽  
Vol 41 (1) ◽  
pp. 703
Author(s):  
I.R. Noble

There is strong scientific consensus that the concentration of greenhouse gases in the atmosphere is increasing due to human activities and that this is leading to changes in the Earth’s climate. Fluxes between terrestrial ecosystems and the atmosphere are a significant component of the global carbon cycle and actions to increase net storage in terrestrial ecosystems (often called sinks) will delay the build up of greenhouse gases in the atmosphere. There is still political debate as to which sinks may be accounted in compliance with the Kyoto Protocol. The decisions made will affect the total costs of compliance with the Kyoto Protocol by a factor or two to four. Geological sequestration may also reduce emissions by an amount of the same order as sequestration in terrestrial sinks. Biological and geological sequestration offer a significant opportunity to buy several decades of time to make an efficient transition to technologies and economies that release less greenhouse gasses to the atmosphere from energy production and industrial processes.


Sign in / Sign up

Export Citation Format

Share Document