The climate system is, apart from anthropogenic forcing and other external perturbations, in a thermodynamically nonequilibrium steady-state. A major difference between fluctuations in nonequilibrium and equilibrium steady-states is that noneqilibrium steady-states violate time reversal symmetry. One manifestation is the presence of persistent probability currents, which form closed loops. In t...

Three-dimensional radar reflectivity fields from a dual-wavelength Doppler polarimetric radar (S-PolKa) deployed in the equatorial IndianOcean are used to evaluate the composition of the population of convective cloud elements during active phases of the MJO. Rainfall in active periods was intermittent, occurring in 11 episodes of about 2–4 days, separated by several nonrainy days. Data for the...

A new model of the Madden-Julian oscillation (MJO) is presented. Cloudradiation interactions in this model make the tropical atmosphere susceptible to large-scale radiative-convective overturning. The modeled MJO takes the form of such an instability, though its behavior is substantially modified by the effects of surface heat flux variability. The dynamics of the disturbance in the model are q...

The effects of artificial night lighting on animal behaviour and fitness are largely unknown. Most studies report short-term consequences in locations that are also exposed to other anthropogenic disturbance. We know little about how the effects of nocturnal illumination vary with different light colour compositions. This is increasingly relevant as the use of LED lights becomes more common, an...

It is well known that the envelope of the Madden–Julian oscillation (MJO) consists of smaller-scale convective systems, including mesoscale convective systems (MCS), tropical cyclones, and synoptic-scale waves called ‘‘convectively coupled equatorial waves’’ (CCW). In fact, recent results suggest that the fundamental mechanisms of the MJO involve interactions between the synoptic-scale CCW and ...

This study investigates 1) the eastward propagation of the Madden–Julian oscillation (MJO) and global occurrences of extreme precipitation, 2) the degree to which a general circulation model with a relatively realistic representation of the MJO simulates its influence on extremes, and 3) a possible modulation of the MJO on potential predictability of extreme precipitation events. The observatio...