Polar areas are equally affected than lower latitudes by rising temperatures associated with climate change. The rising temperatures on a global level are affecting the polar ares equally, but because of the ice caps they have it is more obvious. It takes very little for the ice to melt, and once that starts to happen the whole landscape is drastically changing, but also the whole world feels the effects of it, unlike the lower latitude places were 2-3 degrees do not make any significant changes, at least not on the short term.
El Niño is a climate pattern that describes the unusual warming of surface waters in the eastern equatorial Pacific Ocean. Trade winds and atmosphere are also impacted by El Niño.