During the 22nd Chinese Antarctic Research Expedition （ CHINARE-22, 2005/06） , the atmospheric gas samples near the surface were taken on the Millor Peninsula and adjacent areas, east Antarctica, using Tedlar gas ba...During the 22nd Chinese Antarctic Research Expedition （ CHINARE-22, 2005/06） , the atmospheric gas samples near the surface were taken on the Millor Peninsula and adjacent areas, east Antarctica, using Tedlar gas bags. The methane （ CH4 ） concentration and δ^13C-CH4 in those samples were analyzed in the laboratory. The average value of atmospheric CH4 concentration on this peninsula was （ 1.87 ± 0. 12） × 10^ -6, slightly higher than the global average CH4 concentration. The summertime variation of CH4 concentrations showed a large fluctuation, corresponding to the variation of air temperatures. The average δ^13 C-CH4 was （ - 38.26 ± 0.52 ） ‰. CH4 concentrations and δ^13C-CH4 at different sites varied from 1.74 ×10^-6 to 2. 56 × 10^ -6 and from - 39.31‰ to - 31.25‰, respectively. The factors affecting CH4 concentrations and δ^13C-CH4 values have also been discussed in this study.展开更多
It is generally thought that phosphine (PH3) concentrations exist at the low ng/m3 level during the night and at the pg/m3 level during daylight in the remote atmosphere of the lower troposphere. The first de- termina...It is generally thought that phosphine (PH3) concentrations exist at the low ng/m3 level during the night and at the pg/m3 level during daylight in the remote atmosphere of the lower troposphere. The first de- termination of gaseous PH3 on the Antarctic Millor Peninsula is reported in this paper. No PH3 was de- tected in the air samples around 10:00 when it was sunny. However, PH3 was found in all the 10:00 air samples when it was cloudy or light snow with the average of 75.3±28.8 ng/m3 (n=5). It was also found in nearly all the samples around 22:00 with the average of 87.2±70.9 ng/m3 (n=11). Atmospheric PH3 concentrations around 22:00 were generally higher than those around 10:00 in January and they were almost the same in February. In addition, PH3 concentrations around 22:00 showed a downtrend with the decreasing air temperature, suggesting that light intensity and air temperature had an important effect on atmospheric PH3 concentration. It is very surprising to have found that high concentrations of PH3 exist in the Antarctic atmosphere under the influence of strong UV-radiation and light intensity. The tentative analyses show that dry, cold and very clean atmosphere may be very suitable for the PH3 sur- vival and cause the concentration to increase and accumulate in the local atmosphere. New ap- proaches for the PH3 formation and the process of atmospheric chemistry may exist under such an extreme environment. Atmospheric PH3 may also be from the emissions of local sources.展开更多
基金supported by the National Natural Science Foundation(No.40676005 and No.40730107)the Open Foundation for Key Laboratory of Polar Science(No.KP2008004)
文摘During the 22nd Chinese Antarctic Research Expedition （ CHINARE-22, 2005/06） , the atmospheric gas samples near the surface were taken on the Millor Peninsula and adjacent areas, east Antarctica, using Tedlar gas bags. The methane （ CH4 ） concentration and δ^13C-CH4 in those samples were analyzed in the laboratory. The average value of atmospheric CH4 concentration on this peninsula was （ 1.87 ± 0. 12） × 10^ -6, slightly higher than the global average CH4 concentration. The summertime variation of CH4 concentrations showed a large fluctuation, corresponding to the variation of air temperatures. The average δ^13 C-CH4 was （ - 38.26 ± 0.52 ） ‰. CH4 concentrations and δ^13C-CH4 at different sites varied from 1.74 ×10^-6 to 2. 56 × 10^ -6 and from - 39.31‰ to - 31.25‰, respectively. The factors affecting CH4 concentrations and δ^13C-CH4 values have also been discussed in this study.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 40676005 and 40406001)AAD Science Project 2873 and the Opening Foundation of State Key Laboratory of Soil and Sustainable Agriculture
文摘It is generally thought that phosphine (PH3) concentrations exist at the low ng/m3 level during the night and at the pg/m3 level during daylight in the remote atmosphere of the lower troposphere. The first de- termination of gaseous PH3 on the Antarctic Millor Peninsula is reported in this paper. No PH3 was de- tected in the air samples around 10:00 when it was sunny. However, PH3 was found in all the 10:00 air samples when it was cloudy or light snow with the average of 75.3±28.8 ng/m3 (n=5). It was also found in nearly all the samples around 22:00 with the average of 87.2±70.9 ng/m3 (n=11). Atmospheric PH3 concentrations around 22:00 were generally higher than those around 10:00 in January and they were almost the same in February. In addition, PH3 concentrations around 22:00 showed a downtrend with the decreasing air temperature, suggesting that light intensity and air temperature had an important effect on atmospheric PH3 concentration. It is very surprising to have found that high concentrations of PH3 exist in the Antarctic atmosphere under the influence of strong UV-radiation and light intensity. The tentative analyses show that dry, cold and very clean atmosphere may be very suitable for the PH3 sur- vival and cause the concentration to increase and accumulate in the local atmosphere. New ap- proaches for the PH3 formation and the process of atmospheric chemistry may exist under such an extreme environment. Atmospheric PH3 may also be from the emissions of local sources.
