Widespread pollution of the South American atmosphere predates the industrial revolution by 240 y.

In the Southern Hemisphere, evidence for preindustrial atmospheric pollution is restricted to a few geological archives of low temporal resolution that record trace element deposition originating from past mining and metallurgical operations in South America. Therefore, the timing and the spatial impact of these activities on the past atmosphere remain poorly constrained. Here we present an annually resolved ice core record (A.D. 793-1989) from the high-altitude drilling site of Quelccaya (Peru) that archives preindustrial and industrial variations in trace elements. During the precolonial period (i.e., pre-A.D. 1532), the deposition of trace elements was mainly dominated by the fallout of aeolian dust and of ash from occasional volcanic eruptions, indicating that metallurgic production during the Inca Empire (A.D. 1438-1532) had a negligible impact on the South American atmosphere. In contrast, a widespread anthropogenic signal is evident after around A.D. 1540, which corresponds with the beginning of colonial mining and metallurgy in Peru and Bolivia, ∼240 y before the Industrial Revolution. This shift was due to a major technological transition for silver extraction in South America (A.D. 1572), from lead-based smelting to mercury amalgamation, which precipitated a massive increase in mining activities. However, deposition of toxic trace metals during the Colonial era was still several factors lower than 20th century pollution that was unprecedented over the entirety of human history.

Comparison between real time and flask measurements of atmospheric O2 and CO2 performed at the High Altitude Research Station Jungfraujoch, Switzerland.

First real time CO2 and O2 measurements on the High Altitude Research Station Jungfraujoch (Switzerland) are compared with corresponding flasks samples. Whereas CO2 measurements show a good agreement, O2 compares only moderately. Real time O2 measurements are performed using two different methods, i.e. by paramagnetic and fuel cells. Fuel cell values exhibit significantly higher scatter, but they compare acceptably well with the paramagnetic values when averaging over 228 min (20 point running mean). Continuous measurements are powerful in many respects in contrast to spot-like flask sampling. They help to set up data selection criteria and to improve the robustness of trend calculations. Further, real time measurements help to partition the anthropogenic CO2 increase into ocean and terrestrial biosphere for short-time variations of minutes, hours, days, which are not covered by flask sampling.

Measurements and trend analysis of O2, CO2 and delta13C of CO2 from the high altitude research station Junfgraujoch, Switzerland--a comparison with the observations from the remote site Puy de Dôme, France.

Atmospheric O2 and CO2 flask measurements from the high altitude research station Jungfraujoch, Switzerland, and from the observatory at Puy de Dôme, France, are presented. Additionally, the Jungfraujoch delta13C record of CO2 is discussed. The observations on flask samples collected at the Jungfraujoch station show, since 2003, an enhancement of the oxygen trend which amounts to about 45 per meg/year with a corresponding CO2 increase of around 2.4 ppm/year. This enhancement is comparable with that observed at the Puy de Dôme station where oxygen, since mid 2002, has decreased with a rate of about 50 per meg/year whilst the CO2 increase was of around 1.7 ppm/year but exhibiting a higher variability. Several processes influence deltaO2/N2. However, these processes are marked with different oxidation ratios (O2:CO2) that can be used to distinguish them. The apparent slopes calculated from correlation plots between de-trended CO2 and deltaO2/N2 records as well as between corresponding trends are significantly larger than the observe ratios depending on processes within the ocean, it is to our understanding the only possibility to explain our observations. The stability of the deltaO2/N2 scale is critical in this regard, therefore, it is addressed here and we found no significant scale drift which would influence our trend calculations. In our view more important are criterions on the data selection before trend analysis.