One of the most compelling indicators of long-term climate change is the condition of Arctic sea ice. Here is a copy of the Snow & Ice image for 6/20/2014. There has been substantial ice melt in just the past month. We have nearly three months left in the melt season, which historically ends around the middle of September. It will be interesting to see just how far the ice will eventually recede, especially given the enormous amount of additional heat energy stored in the northern hemisphere. Presently, the average northern hemisphere sea surface temperatures is 1.38° C above the historical average.
This image is part of the Daily Summary compiled at the Climate Change Institute at the University of Maine. There is a lot of rich and intriguing data at their website, which is very well worth bookmarking for regular — even daily — views. Those who are really curious and want to learn more should explore this link, where you can view slideshows of the daily changes.