Nitrous oxide past concentrations

Atmospheric concentrations of (a) carbon methane, and (c) nitrous oxide over the past... 

Fig. 16-3 Illustration of the linked behavior of radiatively important trace species concentrations over different time-scales. (a, b, c) Concentrations of methane, nss-SOj , and CO2 over the past 160 000 years found in ice cores from Vostok, Antarctica (temperature deduced from 02 also shown), (d, e, f) Secular trends in nitrous oxide, methane, and CO2 over the past 300 years, (g, h, i, j, k) Changes in October stratospheric ozone column burden over Antarctica, and chloroflourocarbon, methane, sulfate, and nitrate from south Greenland ice, and carbon dioxide concentrations over the past 30 years. Figures adapted from (a) Chappellaz et al. (1990) with the permission of Macmillan Magazines Ltd. (b) Legrand et al. (1988) with the permission of Macmillan Magazines Ltd. (c) Bamola et al. (1987) with the permission of Macmillan Magazines Ltd. ...

Fig. 17.32 The concentrations of methane in ice of the Dome-C core (EPICA) between 380 x 10 years and 650x10 years in the past vary in-step with the 5D values and hence with the average annual surface temperatures at Dome C. The warm and cold climatic intervals are identified by the MIS (marine isotope stages) numbers from Fig. 17.30 where up means warm and down means cold. The profile of nitrous oxide concentrations also mirrors the fluctuations of 6D. Data for the upper part of the core...

According to IPCC, the effect of human activities on changes in the climate is very likely to have been dominating natural variations (due to, e.g., variations in solar irradiance) especially in the past 50 years. Since the beginning of the industrial revolution, the concentrations of the relevant greenhouse gases (especially carbon dioxide, methane, nitrous oxide, and halocarbons) have increased substantially and now by far exceed natural ranges encountered in the past 650,000 years [1],... 

Fig. 121.2 Concentrations of carbon dioxide, methane and nitrous oxide for the past 10,000 years. (Source IPCC, 2007 AR4 WG 1 Fig. SPMl)...

---