[1] Methane retrievals from near-infrared spectra recorded by the SCIAMACHY instrument onboard ENVISAT hitherto suggested unexpectedly large tropical emissions. Even though recent studies confirm substantial tropical emissions, there were indications for an unresolved error in the satellite retrievals. Here we identify a retrieval error related to inaccuracies in water vapor spectroscopic parameters, causing a substantial overestimation of methane correlated with high water vapor abundances. We report on the overall implications of an update in water spectroscopy on methane retrievals with special focus on the tropics where the impact is largest. The new retrievals are applied in a fourdimensional variational (4D-VAR) data assimilation system to derive a first estimate of the impact on tropical CH 4 sources. Compared to inversions based on previous SCIAMACHY retrievals, annual tropical emission estimates are reduced from 260 to about 201 Tg CH 4 but still remain higher than previously anticipated. Citation: Frankenberg, C.,

We consider charged rotating black holes in 5-dimensional Einstein-Maxwell theory. These black holes are asymptotically flat, they possess a regular horizon of spherical topology and two independent angular momenta associated with two distinct planes of rotation. We discuss their global and horizon properties, and derive a generalized Smarr formula. We construct these black holes numerically, focussing on black holes with a single angular momentum, and with two equalmagnitude angular momenta.

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Abstract. Total columns measured with the ground-based solar FTIR technique are highly variable in time due to atmospheric chemistry and dynamics in the atmosphere above the measurement station. In this paper, a multiple regression model with anomalies of air pressure, total columns of hydrogen fluoride (HF) and carbon monoxide (CO) and tropopause height are used to reduce the variability in the methane (CH 4 ) and nitrous oxide (N 2 O) total columns to estimate reliable linear trends with as small uncertainties as possible. The method is developed at the Harestua station (60 • N, 11 • E, 600 m a.s.l.) and used on three other European FTIR stations, i.e. Jungfraujoch stations. From the N 2 O total columns crude tropospheric and stratospheric partial columns were derived, indicating that the observed difference in the N 2 O trends between the FTIR sites is of stratospheric origin. This agrees well with the N 2 O measurements by the SMR instrument onboard the Odin satellite showing the highest trends at Harestua, 0.98 ± 0.28 % yr −1 , and considerably smaller trends at lower latitudes, 0.27 ± 0.25 % yr −1 . The multiple regression model was compared with two other trend methods, the ordinary linear regression and a Bootstrap algorithm. The multiple regression model estimated CH 4 and N 2 O trends that differed up to 31 % compared to the other two methods and had uncertainties that were up to 300 % lower. Since the multiple regression method were carefully validated this stresses the importance to account for variability in the total columns when estimating trend from solar FTIR data.

Abstract. Trends in the CO and C 2 H 6 partial columns (∼0-15 km) have been estimated from four European groundbased solar FTIR (Fourier Transform InfraRed) stations for the 1996-2006 time period. The CO trends from the four stations Jungfraujoch, Zugspitze, Harestua and Kiruna have been estimated to −0.45 ± 0.16 % yr −1 , −1.00 ± 0.24 % yr −1 , −0.62 ± 0.19 % yr −1 and −0.61 ± 0.16 % yr −1 , respectively. The corresponding trends for C 2 H 6 are −1.51± 0.23 % yr −1 , −2.11 ± 0.30 % yr −1 , −1.09 ± 0.25 % yr −1 and −1.14 ± 0.18 % yr −1 . All trends are presented with their 2-σ confidence intervals. To find possible reasons for the CO trends, the global-scale EMEP MSC-W chemical transport model has been used in a series of sensitivity scenarios. It is shown that the trends are consistent with the combination of a 20 % decrease in the anthropogenic CO emissions seen in Europe and North America during the 1996-2006 period and a 20 % increase in the anthropogenic CO emissions in East Asia, during the same time period. The possible impacts of CH 4 and biogenic volatile organic compounds (BVOCs) are also considered. The European and global-scale EMEP models have been evaluated against the Correspondence to: J. Mellqvist (johan.mellqvist@chalmers.se) measured CO and C 2 H 6 partial columns from Jungfraujoch, Zugspitze, Bremen, Harestua, Kiruna and Ny-Ålesund. The European model reproduces, on average the measurements at the different sites fairly well and within 10-22 % deviation for CO and 14-31 % deviation for C 2 H 6 . Their seasonal amplitude is captured within 6-35 % and 9-124 % for CO and C 2 H 6 , respectively. However, 61-98 % of the CO and C 2 H 6 partial columns in the European model are shown to arise from the boundary conditions, making the globalscale model a more suitable alternative when modeling these two species. In the evaluation of the global model the average partial columns for 2006 are shown to be within 1-9 % and 37-50 % of the measurements for CO and C 2 H 6 , respectively. The global model sensitivity for assumptions made in this paper is also analyzed.