Arctic sea ice has been in decline for several decades and its melting is accelerating. This chart shows how it's in a death spiral. The line represents ice volume data from PIOMAS. Each point is plotted as a fraction of the 1979 value, so that if the volume was half of the 1979 value, the point appears half way from the centre to the edge. The colour of the line starts blue and changes to red with time. If there was no trend you'd see blue and red overlapping, but you can clearly see there is a trend. The September ice volume is plummeting towards zero - it's dropped by nearly 80% in 40 years, so at this rate there will be no summer ice by 2029.