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After a decade of stable or slightly decreasing global methane concentrations, ground‐based in situ data show that CH4 began increasing again in 2007 and that this increase continued through 2009. So far, space‐based retrievals sensitive to the lower troposphere in the time period under consideration have not been available. Here we report a long‐term data set of column‐averaged methane mixing ratios retrieved from spectra of the Scanning Imaging Absorption Spectrometer for Atmospheric Cartography (SCIAMACHY) instrument onboard Envisat. The retrieval quality after 2005 was severely affected by degrading detector pixels within the methane 2ν3 absorption band. We identified the most crucial problems in SCIAMACHY detector degradation and overcame the problem by applying a strict pixel mask as well as a new dark current characterization. Even though retrieval precision after the end of 2005 is invariably degraded, consistent methane retrievals from 2003 through 2009 are now possible. Regional time series in the Sahara, Australia, tropical Africa, South America, and Asia show the methane increase in 2007–2009, but we cannot yet draw a firm conclusion concerning the origin of the increase. Tropical Africa even seems to exhibit a negative anomaly in 2006, but an impact from changes in SCIAMACHY detector degradation cannot be excluded yet. Over Assakrem, Algeria, we observed strong similarities between SCIAMACHY measurements and ground‐based data in deseasonalized time series. We further show long‐term SCIAMACHY xCH4 averages at high spatial resolution that provide further insight into methane variations on regional scales. The Red Basin in China exhibits, on average, the highest methane abundance worldwide, while other localized features such as the Sudd wetlands in southern Sudan can also be identified in SCIAMACHY xCH4 averages.

The ALMA North American and European prototype antennas have been evaluated by a variety of measurement systems to quantify the major performance specifications. Nearfield holography was used to set the reflector surfaces to 17 µm RMS. Pointing and fast switching performance was determined with an optical telescope and by millimeter wavelength radiometry, yielding 2 ′′ absolute and 0.6 ′′ offset pointing accuracies. Path length stability was measured to be 20 µm over 10 minute time periods using optical measurement devices. Dynamical performance was studied with a set of accelerometers, providing data on wind induced tracking errors and structural deformation. Considering all measurements made during this evaluation, both prototype antennas meet the major ALMA antenna performance specifications.

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