We report on the marginal detection of cosmic shear on sub-arcmin scales with archive data from the STIS camera on board HST. For the measurement 121 galaxy fields with a field of view of 51′′ × 51′′ are used to obtain an rms cosmic shear of ∼ 4% with 1.5σ significance. This value is consistent with groundbased results obtained by other groups on larger scales, and with theoretical predictions ...

Prefrontal squall lines are mesoscale convective systems that often cannot be linked to any preexisting organizing mechanism. This suggests the possibility that they are self-forced disturbances, driven by a cooperative interaction between convective and larger scales. To investigate this hypothesis, a wave-CISK model is developed for two-dimensional disturbances in a baroclinic basic state wit...