I first saw this video at Planet 3.0 a fair while ago and have seen it posted again since. I find it very uplifting despite being a jaded climate blogger of many years. There are many other science-based music videos at www.symphonyofscience.com and I have listened/watch most (all?) of them, but this is the best as well as being on topic here.
I think it is just about the perfect mix of the various elements of outreach needed to motivate the general public: explanation, urgency and optimism.