A new NASA analysis of 30 years of satellite data suggests that a previously observed trend of high altitude clouds in the mid-latitudes shifting toward the poles is caused primarily by the expansion of the tropics. (giss.nasa.gov)
You will pass through the threatened higher altitude Cloud Forest, which is home to many attractive humming -LSB-...] (tourthetropics.com)
There has been a lot of interest in the relationship between ENSO and the AAO with better correlation in some seasons than others but little realization that the northern trades and the southern exhibit very different behaviors, that the Arctic contributes, that the flux in ozone comes from the Arctic more than the Antarctic, this affecting mid latitude high altitude cloud cover. (wattsupwiththat.com)