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Branched glycerol dialkyl glycerol tetraethers (branched GDGTs) are membrane lipids presumably derived from anaerobic, heterotrophic soil bacteria. Empirical studies have shown that the composition of branched GDGTs in topsoils varies in degree of cyclization and methylation (expressed as CBT and MBT, i.e. cyclization and methylation index of branched tetraethers) depending on soil pH and mean annual air temperature (MAT). Here we present results from three case studies, namely three well-studied loess-paleosol sequences (LPSs), in which we measured the branched GDGTs in order to test the applicability of these biomarkers for paleoclimate reconstruction. The results show that major disagreements exist between expectations based on available stratigraphic, pedological and geochemical data on the one hand, and GDGT-derived reconstructions on the other hand. Caution is therefore advised when …